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How can I motorize 42077 Technic Rally Car with LEGO Power Functions?
The new 42077 Technic Rally Car set looks really nice, and even has a built-in steering system which can be controlled by a gear on the top. There's also a fair bit of extra room inside, is there a way to add Power Functions elements to make it remote controlled?

Please add the “Annual-support” tag :)

@PhilB. I've added that in.

With some Power Functions elements and a few extra pieces, it's pretty easy to turn the Rally Car into an RC car.
Here's a quick demo video of my design in action.

And here are the instructions I made for it.
Required extra pieces
First you are going to need some extra pieces:

Power Functions:

1x - Servo Motor
1x - IR Receiver
1x - Battery Box
1x - L-Motor (alternately you can use an M-Motor but it is not as powerful)

Technic:

1x - 5L beam
2x - 2L thin beam
4x - Axle Pin with Friction Ridges
2x - 3L axle

In addition to that, you will need a Power Functions remote, and possibly some extra pieces to build the remote. If you don't have a remote already, there are instructions for one at the end.
Disassembly
To add power functions, you will need to disassembly it a bit to remove the engine block and manual steering system.

Remove doors.

Remove roof sides.

Remove roof gear and pull the blue pins out one step.

Take the center of the roof off with the front window frame.

Detach the trunk.

Detach the hood.

Remove seats.

Remove fire extinguisher.

Remove manual steering.
Removing the steering system is a little tricky, but doable.

Locate the place where it attaches to the back.

Push up on the grey piece to detach it from the small black pieces, so you can slide it back and remove all the yellow pieces.

All of these pieces should be removed.

Also remove the black and blue pieces that hold it.

After they are removed, the engine block will be easier to remove.

Removing engine block

On the back, locate this area.

Partially detach it temporarily.

Remove the gear and axles.

Reattach the section.

From the underside, locate where the engine block attaches at the back.

Push up to detach the engine block and the white pieces and pins that attached it.

Check alignment
At this point, you going to want to make sure the front gear attached to the gear rack for steering is perfectly vertically aligned like so. If not, slide the pin out and adjust it. It needs to be vertical for the servo motor to attach to it.

Locate pieces
In these sections you removed, you will find some other pieces you will need.

Disassemble them to find these pieces.

Add drive motor

Build this.

From the underside, position it to slide in the back into the differential area.

In this area, you are going to need to add the black gear.

Hold a black gear in place, then slice the axle and motor into the holes.

Add steering motor

In the front, flip up this white panel.

Slide the dark grey in the gear out one stud.

Build this bracket.

Insert it here, then slide the red pins out one stud.

Through the seating area, insert the servo motor into the bracket and push the red pins back in.

Now if the axle is correctly aligned, you can just slide the axle into the motor.

Flip the panel back down.

Adding Battery Box

Build the following.

Slide the batter box into the back here.

On the sides, attach it with the pieces you just built.

Re-assembly

Reattach seats.

Reattach hood.

Reattach roof center, and slide the blue pins back in.

Reattach the trunk to the blue pins.

Hold the trunk in the up position, and reattach the roof sides.

Reattach the doors.

IR Receiver

Attach black pins to the receiver, and attach it to the spoiler.

It's tricky, but run the wire through the crack down to the batter box.

Now run the wires from the motors up through that crack, and attach to the IR receiver, servo to blue, engine to red.

Turning the car on.
Turning the car on/off is as simple as opening the hood and switching the orange switch on the battery box.

Remote
You can build the following remote with a few extra pieces.

Power Functions:

1x - IR Remote Control

Technic:

2x - Axle Pin 3L with Friction Ridges
2x - Axle and Pin Connector Angled #1
2x - Axle 2L
1x - Liftarm 1 x 4 Thin with Stud Connector (or the version without the stud connector)
1x - Wheel 30.4mm D. x 20mm (or some other wheel rim)

Build sticks.

Attach sticks.

Build arm.

Attach arm.

Attach wheel.

Happy building!

This is FANTASTIC

Great writeup! This is thorough and beautiful. Nice work!

Nice work and write up! I would suggest popping out the steering limiters on the steering rack as well. Much better turning radius without them.


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Why do LEGO bricks keep their value even though they are still being produced?
I am curious why prices of individual bricks do not decrease because of increasing number of bricks produced. As an analogy to currency, when some government is printing money, their value gets lower. But this does not apply for bricks.
I don't think that bricks around the world are utilized in the same rate they are produced. Most of people know the value of that "toy" and don't simply throw them out when children don't play with them.

Banknotes and coins tend to have very little physical value relative to their face value.  LEGO bricks usually are valued more for their function rather than the material value. In most cases it would not be cost effective to buy LEGO bricks just for the material itself.
Well treated bricks can be handed down, generation to generation. A 2x4 brick made 30 years ago is virtually identical compared to one made today. A lot of construction toy brands hold their value over time.
Traditional toys lose their value as they no are longer fashionable or they wear out. A broken doll house might not be worth keeping but a LEGO set with a few missing pieces can still be built with spare parts or re-built into something else.
Individual bricks do actually decrease in value relative to the increased production, particularly soon after a new part has been released as LEGO introduce the part to more and more sets in different colours. This piece released last year is worth about 1/5th of what it once was when it was only available in two high priced sets.
Certain parts also experience a large increase in price after they are discontinued as they consequently become harder to find. Some parts (rubber, electronics, cloth) deteriorate faster than plastic bricks.

I was hoping someone will have a good explanation to this interesting question. Good work! :)

I feel it necessary to point out that I think the durability of LEGO is a bit romanticized.
When coming out of my dark ages, there was very little I could do with my old LEGO, the pieces were scratched, had teeth marks, were yellowed...
I haven't thrown this LEGO away, but it's stored and not used, hence not in circulation and hence has no economic value.
I think there is definitely a constant need for new and shiny bricks, unlike currency where newly printed money has exactly the same value as old.
Also I'd like to point out that selling individual pieces is not the main activity of LEGO, they mainly sell entire sets.
Deriving brick prices from set prices is a bit pointless as its hard to factor in the value of the set (the box, the instructions, licensing,...)
I think the main market place for buying and selling individual pieces is bricklink, and there you definetely see the economic principle of supply and demand in action, as already pointed out in the previous answer.

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


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amazon.fr hints that the Boost app will be available on phones?
At this moment (end of the year, 2017), the description for Lego Boost on the french amazon site includes the notice:

Enfin, l'application sera également disponible sur smartphones dès les
  vacances de fin d'année.

(translates to: Finally [it's after the list of compatible tablet Os'],  the application will also be available on smartphones from the end of the year vacation.)
Has anyone read anything about this elsewhere? I'm failing to find anything on google, the LEGO site or the German or UK Amazon sites.

V1.4.4 on Apple App Store state “support for mobile phones”, and it does install fine on iPhones. Finally.

V1.4.3 on the Google Play store also lists "support for mobile phones" in the "What's New" section and can be installed on my Samsung S7.

The version on the Amazon app store also installs on phones. I've installed it and started it up but I don't have the Boost kit to test.

Installs and seems to run on my smartphone (galaxy A5), but haven't opened my boost set yet to verify further. I think lego indeed recently started supporting smartphones.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


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Does anyone know which set included a 2 piece moon?
I have a 2 piece moonlike miniset that apparently came included in some sort of larger space set. Anyone know what I'm talking about and where it comes from?
The collection includes a rocketship base with light-up and sound rockets. I assume its the same set as the moon. It's definitely not a Star Wars set.

Both the Countdown Corner and Mission Control sets included both a "Light and Sound" rocket and a multi-part "moon" in the form of the "Rock Arctic Globe":

Yes! It was countdown corner! Thanks! (I also have the side satellite-like pieces.)

If you mean something like this, a 11x11 ball

Then this link gives each pass and you can click through and find all the sets they came in https://www.bricklink.com/v2/search.page?q=Cylinder%20Hemisphere%2011%20x%2011#T=A
They have been used for moons, planets and a deathstar


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Which LEGO set is best suited to build robots?
My goal is to build some educational robot kits for kids and so I'd like to know if there are any LEGO sets that let you build almost anything or can you only can build the specific model that the package is designed for?
I am looking for general parts to build different sorts of robots but I  do not mind about electronic parts (motors, boards, sensors, etc. as I can build or buy those), I'm really after mechanical parts (gears, axles, beams, etc.).
I do not want pay for moulding and prefer to use something like LEGO parts, but I am unsure which LEGO set will offer the most flexibility to build anything I want?
Also if there are other universal building products other than LEGO that I could use I would be happy to know.

Your question is not so clear, but it seems like you want to build robots and you want Technic pieces. Then Lego Mindstorms is the product you should buy. While not formally part of the Technic range, it contains only Technic elements in addition to the special electronic Mindstorms parts.
You can also take a look at Lego BOOST, a lightweight variant of Mindstorms, but that is not as much oriented around Technic pieces.
If you don't want the electronics, then you could consider the Bucket Excavator which contains a large number of elements for a fair price. Alternatively maybe you should also look at Meccano.

Thank you for answer. My English is not good and maybe can't explain good, but you got my meaning true. I do not concern about electronic parts like motors, sensors, electrical boards, etc. I can buy or build them by myself. My question is about mechanical side. I like to know which logo package is more complete and more universal to build almost all mechanical part of the robot you want!

@user145959: Look at the Bucket Excavator which contains a large number of elements for a fair price. Maybe you should also look at Meccano.


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Infrared sensor behavior
I'm developing a small program with the LEGO's Ev3 development tool. I'm trying to make the robot rotate, 30° at time, and if the infrared sensor detects something then make something and stop. Here is my current program:

The result is odd: it makes a few loops, than I can see the sensor turns off for a few seconds and then it is completely unresponsive, even if I stop the program and run other programs! I have to turn it off and on again to make it work.
The sensor is on port 4, and it works with programs developed on the ev3 itself.

How can you "see" that the sensor turns off? Perhaps you have it mistaken for the Ultrasonic Sensor. They are similar shape, but the ultrasonic sensors has LEDs so you can "see" if it working. The Infrared sensors does not have LEDs, just red paint, so you cannot "see" if it is working.

You are right, I was using ultrasonic sensor! Thank you!

@DavidLechner Please consider posting your comment as an answer.

Try waiting longer - one second or one and a half. And you were using the ultrasonic sensor but in the program you use infrared sensor block.
You can switch to port view prior to running your program to verify that your sensor is of the expected type and works.


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What are the structural difference between a minifig and a minifig on a keychain?
Are there any differences in the components or construction of keychain minifigs compared with regular minifigs from sets?

A minifig on a keychain and a regular minifig are essentially the same. They are made of the same components. A couple of additional procedures turn regular minifigs into keychain minifigs.
1.) There is a long screw inserted through the head and neck-post of the minifig to be able to attach the keychain to the loop at the end of the screw. If you remove the screw, there will be a small hole left inside the stud on the head, and on the neck-post.
2.) The leg assembly is fused to the torso assembly to make sure they don't separate during use as a keychain.
In addition, keychain minifigs are made in China, so there is a slight difference in how they look. The plastic has a duller and sometimes a bit more opaque appearance compared to regular minifigs. The printing, however, is the same quality, which is what most people focus on. The difference in the shine/opaqueness is usually only noticed when the keychain minifigs is placed next to an identical regular minifig.

Do we know if the legs are glued on or if the plastic is molded differently to make it more resilient?

pretty interesting. Does the slight difference of China figs also apply to figs from the 90ties?

The plastic pieces for the torso and legs are exactly the same as regular minifigs. They are not glued, but the legs are fused to the torso with a solvent, that actually loosens the surface of the ABS plastic and allows the molecules to combine. Once the solvent evaporates, it leaves behind a cleanly fused surface with no residue at all.

LEGO has been using two types of solvents through the years to "glue" minifigs, sculptures, etc. One is called MEK (methyl-ethyl-ketone) and at some point they switched to GBL (gamma-butyrolactone).

@Fabian, the collectible minifig series didn't start until 2010. At that time, LEGO didn't have their own factory in China, but worked with a partner. Now they have their own factory and are more in control of the quality. According to the official LEGO history site,  https://www.lego.com/en-us/themes/lego-history/ LEGO didn't start working with Chinese partners until the 2000s, although it is possible that some of their non-brick items were made there even before (stationary, school-supplies, home décor, etc.)

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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Lego track switch doesn't close properly
Just two weeks ago, my kid got a 60198 cargo train and we added a set of 60238 switching tracks. With two (out of three) switches we have the problem that the switch doesn't close properly anymore to perform the lane change (the position to go straight is fine). As you can see the movable rail part doesn't completely close against the fixed rail track, causing the wheels to miss the turn. The train either just goes straight (best case) or de-rails (worst-case).

Any idea what the cause is, and is there anything I can do to fix this? This happened with two different sets, bought about 5 months apart (but put in use at same time) with two different vendors across Europe, so I'd be surprised this to be a 'bad batch'. I've also tried reversing the locomotive to check it isn't because the wheels are misaligned, but both the powered and non-powered wheels give the same result. On first sight it looks like there is a spring in the switch which got stuck/compressed/..., but I have no idea how to open this without breaking the track.
The correct "go straight" switch position is:

I'd look at the underside of the switch, to see if there is any mechanical blockage of the moving parts.

Warning: LEGO pieces were harmed for this answer
How the switch works

So, how does it work then? Well, let's open it up!

The back plate is held into place by 14 pins. We'll carefully pry it open with a knife. Alternatively, we could use a drill bit to slowly scrape off the pinheads.
Both methods are destructive. The back plate needs to be glued back on later.
Once we can lift off the backplate, we already got the slider.
Next we'll unplug the switch. Let's take a pair of pliers and carefully -just a bit!- squeeze the peg, then push it out.

Yellow: The slider is of a soft plastic. Notice the oval hole with a nose. When you move the slider this bit gets squeezed and then snaps into position. There's two stops, they have a figure 8 shape.
Red: At the end of the slider there's a single tooth. This tooth flicks
the switch.
Green: The switch has a peg and a spring. The spring has two legs.
The tooth    is supposed to sit right between them.

What's next?
So much for starters. Now, what about your points?
In any case, use some compressed air first. Switch them repeatedly. Maybe it's just a grain of dust. Still not functioning properly? Can you still return them?
Okay. Let's triple troubleshoot:

Is the slider stuck?
Can it move freely? Does it 'snap in'?
Does the spring have enough tension?

If the slider's malfunctioning, you'd have to remove the back plate. However, if the spring's your suspect there's a less destructive way.
How to access the peg only

In theory, one could try to pry out the switch with a flat
screwdriver. I didn't dare it. Parts could warp, the peg could break
and I think LEGO did their best to prevent creative kids from doing
it.

But take a look at the back plate. You can barely see it, but there's a circle. It's right on top of the peg.

I took a drill bit and started to slowly scratch off some of the plastic. Once the tip was through, I finished off the rest with a scalpel.
Take your time! The plastic is quite thin and the peg's right under it.
I could now easily access the peg with my pliers and push it out. I adjusted the spring and lined everything up.
How to access the spring
This might also work, but I don't recommend it. I gave it a try. It's way too fiddly.

Take a scalpel and cut a hole in the side of the switch.
Now you can take a peek inside. See if the tooth is off-center. If so, try to lift the corresponding leg of the spring with a needle. Good luck.

Wow, that is a thorough analysis, illustrated with great pictures and, combined with the sacrifice of the switch, the upvote is more than deserved!

@zovits Thanks! Now that we know the hidden parts and how they work, somebody might come up with a less invasive (i.e. destructive) idea. After all, how pointless are points that aren't switching...!

Okay, this post is closing in 2 years old, but I have found it looking for a solution to my problem, so others may find it too. I found out two important things:

You don't need to cut or drill the switch to get to the offending spring. You can lift the pivot peg out getting at it from the top.
If the spring is FUBAR or missing, you can actually 3D print it.
Full story here: https://www.biasedlogic.com/index.php/fixing-lego-railroad-switches/

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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Can you identify these arch-way pieces
I'm considering starting a project inspired by some of the Arab-style buildings I've seen. Most of them use a sort of curved archway around the windows. I can't figure out how to duplicate it. Can anyone identify the pieces used here to form the curved archways?
Any other suggestions for making a cool arab scene (for a relatively new builder)

It would help the volunteers here if you would include at least part of the picture in your questions, as well as the link to the full version.

Your question have two questions - looking for parts to identify and ideas for your MOC. If you need suggestion regarding last bit please split this question and submit another question for your inspurations.

You are, most likely, interested in identifying following arch:
Brick, Arch 1 x 3 x 2

The other arch as seen in second picture is the following one:
Brick, Arch 1 x 3 x 3


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Can you identify these column decorators?
I want to decorate some columns with these little round ionic scroll-looking things. Does anyone know the part number?

Brick, Modified 1 x 1 with Scroll with Hollow Stud
https://www.bricklink.com/v2/catalog/catalogitem.page?P=20310&idColor=2


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What kind of software can I use to design LEGO MOCs?
What kind of software can I use to design LEGO MOCs? I hear the LDD is not so good to use so is there alternative software I can use?

See also LEGO Digital Designer Alternatives for an original list.

A popular alternative is stud.io, provided by Bricklink.
Another possibility mentioned by Alex in the comments is LDCad.

Just to add to this, stud.io is the typical go-to software these days. LDD is (in my opinion) simpler to use, but has pretty much been abandoned by Lego at this point. Both softwares are liable to change now that Lego owns BrickLink.

thank you for your answer! do you know if it is possible also to work in stud.io with other 3d-files or only with bricks that are pre-integrated? So if i would have designed new bricks could i use them too?

I would suggest adding LDCad as an option. It was a go to software prior Stud.io for those who prefer LDraw parts. However it is still quite good. Although might be preffered by people with more challenging requirements.

@fabian I don't know if stud.io supports custom pieces, but LDraw certainly does.

I generally agree with both Alex and MindS1, but overall, I think the initial question might fall into a realm of too many varied opinions to be able to choose just one program. If someone was building a shed in real life, how can someone say that the best tool to use is a hammer? How does one cut wood with a hammer? how does one strike nails with a saw?  I've used LDD for years, so LDD is my main go to, but I use other software also to perform tasks LDD can't do. I think the original question could be re-worded differently by asking, "What program do you use, and most importantly explain why?

@RinRio-Oki Asking which one is the best would certainly be opinion based. But OP is simply asking about alternatives, and so the question can be answered objectively.

@  zovits supports GoFundMonica Fair enough.

In the comments you asked,

...do you know if it is possible also to work in stud.io with other
  3d-files or only with bricks that are pre-integrated? So if i would
  have designed new bricks could i use them too?...

Looks like Brinklink also offers a tweak program to make custom bricks called PartDesigner, that's able to export right into Stud.io.  I've never used it, but it might be promising to you.

The kinds of software used to design LEGO MOC doesn't necessarily have to be solely confined to Computer Aided Design programs.
We can get really creative and exploit functions of programs never intended to be used for MOC bricking.
Enter: Adobe Photoshop - PS's main role is a visual graphic editor, but it does something strange if an image is magnified past 400%.  PS breaks the image down into nice square shaped pixels. Perfect for making LEGO MOCs.
I use the PS squares created in two main ways:

1) Top View pixel creation - Where the scale is a perfect 1:1.
2) Side View pixel creation - Where two 1x1 plates stacked on top each
other, almost equaling a PS square.
Note: A 2x2 plate stacked on a 2x2 brick makes a nice a square also,
but this will increase the size of our creation.

Well, anyway, the magnifying function is clearly not intended to brick out an outline, but it works well here.
I'm sure there are many other methods within and outside this specific graphic program to aid us in our build.  PS does has a pixelation filter, and outside the program there are LEGO mosaic makers, but this interesting quirk breaks a solid image into pieces, where with minimum time and effort, a more precise stud length can be quickly counted out.
Speaking of counting, it will also help to know your LEGO Math here.  So, when using Side View, 3 Plates = 1 Brick.  Pixels of the same color can be group and merged into money saving bricks.
Here are two examples of Top View.

Below is an example of one Side View pixel method I'm currently working on.


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What is the wall thickness of a lego brick?
Different sources show different thickness for the wall. I've seen everywhere from 1.0mm to 1.8mm. I need to know with a high degree of confidence since I'm making an aluminium lego piece of a school assignment, so my wall thickness will be smaller.  Because I only get to have one attempt, I can't try it with one piece and adjust the model for a second run.
The image below shows the dimension in question, with this drawing taken from another SE question, made by SE user Bartneck

Original source: https://bricks.stackexchange.com/a/11131

Hi Mark, the top-voted answer in the question this image came from gives the dimension of the wall of a 1x1 brick as 1.6mm, while the technical drawing this came from was actually in mm, so the wall thickness there is 1.2mm.

Considering your very specific needs, you might want to get the actual brick you're going to duplicate and use calipers to measure it exactly

The precision I need would need an anvil micrometer, which i don't have :(

According to this answer, a 1x1 brick has walls 1.6mm thick - this fits in with the base unit of 0.8mm that is used throughout all LEGO elements, as per pcantin's answer on the same question.
The 1x4 brick in the image you've included shows walls of 1.2mm, while a similar drawing on bartneck's site for the 1x4 Technic Brick with Holes shows a wall thickness of 1.5mm, which is closer to the expected 1.6mm. Curiously the Stud diameter is exactly as expected at 4.8mm.


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Help with popcorn cart wheels
Can someone identify the wheel attachments for a LEGO popcorn cart wheel like this?
How do we connect it to the axle? Is there a good tutorial on LEGO wheels somewhere I can read?

The second one is almost entirely made of clone-brand parts that haven't existed in the LEGO universe, and those include the wheels. And that means that we can't help you with them.

@mindstormsboi No, all bricks are authentic in this, except printing and or stickers...

The "wheels" are really the hubs, mostly from the various Speed Champions cars among others.
The inside of the wheel takes a standard stud, so you should be able to use:

Plate Modified 2x2 with Pin Hole
Technic Pin 1/2
Wheel Cover 5 Spoke

Beyond the primary question of how to build these particular wheels, there are a few common themes among wheels and axles across the system (there are clearly more than those shown here, but these cover most of the typical "official" connections you'll come across at the moment):


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What is this? Is it LEGO? Dark Green, detailed mouldings, roughly trapezoid shaped
I've been sifting through a few gifted bins of LEGO with a small percentage of trash and clone-brands stuff.  I've had pretty good luck with finding new and strange LEGO pieces on bricklink, but this one has me stumped.

I don't see LEGO printed anywhere on it.  Another discouraging factor is on the bottom where I see numbers that would suggest it is not LEGO:

But it fits Technic pins perfectly so maybe it is something LEGO that I've never seen before:

So have I been lured in by some clone part or is this a real LEGO thing?

That's LEGO piece - 47299 - Bionicle Toa Metru Knee Cover. You can see © sign in LEGO font as well as "47299" part number on the bottom, both of which confirm this is legit item.


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Selling sets on eBay - should I buy missing bricks and figures to complete a set?
I am preparing to sell my daughter's LEGO sets on eBay - Elves and Star Wars.
We have completed the mammoth task of finding the pieces we have from each set, but some sets have missing pieces and figures.
We are purchasing pieces to make the sets complete - that's ok for the inexpensive pieces, but one set has two missing figures (Tarkin and the A-wing Pilot) - to replace them both will cost 16 GBP. The set is Star Wars: Vader's Tie Advanced vs A-Wing Starfighter (75150).

I'm hoping to sell it for around 100 pounds. Is it worth it to buy the missing figures - will we make back the money we spend or would it be more cost effective to sell it with the two figures missing?

Is it worth it to buy the missing figures - will we make back the money we spend or would it be more cost effective to sell it with the two figures missing ?

This boils down to the following:
SALE PRICE OF COMPLETE SET > SALE PRICE OF INCOMPLETE SET  +  BUY PRICE OF MISSING PIECES

If that is true, you stand to profit from completing the set, barring any other expenses (like transaction fess, currency conversion fees, shipping and handling costs, etc.)
So now to find the values of these items (you have already mentioned that it costs 16 GBP to replace the figures) we can turn to Bricklink's price estimates and lots for sale to see that used, complete lots are for sale for as low as 63€, and even new, sealed sets can be gotten for 70€, so your 100 GBP price is way over the market niveau. This brings our test to this state of completion:
63€ > SALE PRICE OF INCOMPLETE SET + 16 GBP

You don't specify which two of the four figures are missing, that will definitely affect the desirability of the incomplete set (for which I can't find any closer estimates), so lets find some lower and upper margins.
From Bricklink again we can see that Vader costs on average 15€, Tarkin 9€, and the generic pilot along with Sabine Wren 5€ each. So the savvy collector could buy the two missing figures (if they are interested in having them) for anywhere between 10 and 24€. This gives an approximation for the difference between the prices of a complete set and your incomplete one: the incomplete set would probably sell for about 39-53€, depending on which figures are missing.
By plugging the correct value into the inequation you can then get the answer for your question as stated, but I think the most important conclusion is to use Bricklink for such price analysis and the realization that your asking price is probably too high for most of the informed buyers.

Note to other site users: I realize this Q&A is really specific to this particular scenario in this particular time, but I tried to turn it into a generic how-to on finding the relevant information and calculating the answer that hopefully would serve future visitors as well. Nonetheless, if the community deems this off-topic or too narrow, I'm fine with closing and/or deleting.

That's great, thank you. That was helpful. I was going to put it for sale on ebay for about 50 and imagined i might get 100 but you're right, i won't ! the missing figures are tarkin and the pilot. thanks again.

I'm glad I could help, if you could take the time to accept the answer as outlined in the [help], it would signal to the other users that this issue has been resolved and needs no more attention. While you are at it, feel free to take the [tour] too to learn more about the site :)

Having a general answer is important, but having the specifics makes it more accessible.


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Hair and head for MTG Chandra Ablaze
Is there any female head and hair that can approximate the picture from the MTG card "Chandra, Ablaze"?

I don't even have to have the goggles, I'm just looking for that "crazy psycho chic" look.

Perhaps Ghost Rider? "Minifigure, Head, Modified Alien with Trans-Orange Flaming Hair and Skull with Yellow Eyes Pattern" https://www.bricklink.com/v2/catalog/catalogitem.page?P=26990pb02

The answer by RSchulz has a much better "hair" than I was able to find, but I did find a couple encouraging heads by searching for "angry face". Edit: Since the hair RSchulz found is not detachable from the head, I added hair at the end of the post.
They look like they're meant to be inside hoods/helmets so some modification (color matching, removing edge lines) may be necessary depending on how realistic or close-up you want to go.

Minifigure, Head Dual Sided Balaclava with Face Hole, Orange Eyebrows, Cheek Lines, Smile / Angry Pattern - Hollow Stud

Minifigure, Head Dual Sided Balaclava with Light Nougat Face, Red Eyes, Firm / Angry with Gritted Teeth Pattern - Hollow Stud
And the best hair I can find is this one:

Minifigure, Hair Ponytail High with Orange Flame Pattern

I wasn't able to find any standalone trans-orange flaming hair pieces, which really limits the flexibility of any design. The best I found was the head suggested by RSchulz. Note that this part does come in a number of colors and prints. Another possible option might be the Firestorm version:

Another option that doesn't look as much like fire but that gives more flexibility for selecting an appropriate face may be Syndrome's hair:

Nobody has posted anything better, so I'll try it as an answer:
Perhaps Ghost Rider?  Minifigure, Head, Modified Alien with Trans-Orange Flaming Hair and Skull with Yellow Eyes Pattern

Is the flaming hair fused onto the minifig head, or is a separate, removable piece?

Unfortunately, it's fused. I like the idea of Syndrome's hair!


text:
How do you sync the LEGO high speed train remote?
How do you sync the LEGO high speed train remote?

It is not clear what you are asking. Can you please give more details? Perhaps you mean "sync" as in synchronize instead of "sink"?

My answer to this question might help: http://bricks.stackexchange.com/questions/4870/lego-remote-controlled-cargo-train-not-working

I'm going to take a stab at this. Presumably you're asking how to make the train remote properly control the train. There are two things to consider: 1. Which channel to use, and 2. Motor direction.

Channel: The train remote features two wheels which can be used to control two motors independently. One has a blue line and one has an red line. These correspond to the blue and red markers on the IR sensor. Also, the IR sensor and the remote have an red  sliding tab with numbers 1-4. These need to be set to the same number. So check on your IR sensor and see which number your slider is set to, and which side (blue or red) your motor is connected to. Then make sure you set the slider on the remote to match the IR, and use the appropriate wheel.
Direction: There are two ways to control the direction the train goes when you turn the wheel. One way is to flip the polarity switch on the train battery box. The other way is to flip the direction switch on the remote. If you find the train goes backwards when you turn the wheel meaning it to go forwards, just flip this switch.

Aside from these cases, there is nothing else to configure about the remote. As long as your batteries are fresh and your train is wired up properly, it should work just fine with any combination of sensors and remotes. You can even use one remote to control multiple trains as long as each one is on a separate channel/colour.


text:
What is this piece and what is its number?
Does anyone know what number piece this is?

Looks like it's Support 2 x 4 x 5 Stanchion Inclined 4476a or 4476b.


text:
Lego 3804, Mindstorms Robotics Invention System 2.0 on Windows 10
I gave my grandson (11 years old) the LEGO 3804 Mindstorms Robotics Invention System 2.0. He built a couple things and when he tried to install software to program what he built, the computer would not accept the download. He is running Windows 10.
As a result he can't really use the system. Are there any suggestions or advice from anyone out there to help. I feel terrible about this.
Thank you for your time and expertise.

Works for me:

Download Oracle Virtual Box
Download Microsoft Windows ME (4.90.3000) (OEM Full)
Get the stuff to work
Last but not least: download the VBE9X drivers and install them in Windows ME

That set has an RCX in it, is that right?  I have several suggestions for you:

Have you tried running the software/installer file in compatibility mode?  I understand this software was designed for Windows 95 or 98.  If this is the case, there is an option in Windows to 'run in compatibility mode' by right clicking the .exe file, selecting 'properties' and then under the compatibility section, select whichever operating system the software was originally designed for.
I have found this article which may provide you with a
tutorial.  I am not personally familiar with the set, but I assume this software will work.
Failing all else, I suggest you try Brixc Command Centre .  This uses a derivation of C for programming your robot which, as I understand is not too different from the original Lego software.  This is freeware and allows you to program not only the RCX, but other versions of Mindstorms robots if that is of interest.  I personally use this all the time with my Mindstorms NXT sets and it works a treat.  It's a great way to introduce programming to people as well!

Hope these suggestions are of help!

I found I could not get the Mindstorms NXT 2.0 software to load on my Windows 10 PC because LEGO revoked the security certificates and wants you to run the newest software. The latest version of Mindstorm software (EV3) seems to load and run a Mindstorms NXT 2.0, however, you lose the remote control via Bluetooth and the ability to update NXT Firmware on the brick if you use the latest. If one has a real need to load the software on Windows 10, I found a method to do so.

Activate the Administrator account on your Windows 10.  I found the only method that worked for me was to Search for from windows menu "Computer Management" and run this.
Open the folder Users, and double-click the Administrator account.
Uncheck the option for Account Is Disabled, and click OK or Apply.
Exit Computer management
Click the windows button and select "Switch User" from arrow button on shutdown
Click to enter Admin account
Start Powershell as an administrator
In Powershell, type, D:Setup.ext where D: is the location of the mindstorms NXT 2.0 Setup file.
When you are done, it would be wise to re-hide the administrator account to avoid someone accidentally going into it and causing damage to Windows.

I needed this because our NXT system has some special 3rd party sensors that drivers exist for NXT 2.0 only.
As with any bypassing of windows security features, be wise about how you make use of this approach and touch nothing more than is noted.  There are plenty of "how to activate administrator" account help pages but nobody seems to note that Powershell run under the administrator account allows you to load software with revoked certificates. Never load anything you are not 100% sure is truly safe to run with an approach like this.  You could load potentially dangerous software if it is not verified as safe. I hope this saves someone the frustration and days of time I spent figuring this out.

authors: Преводи и Легализация Варна СА


text:
Can i change the way the ir remote works?
I bought an EV3 and the first thing that I want to do with it is control models with the remote.
I finally discovered how to do this after a long search.
It can control the Formula EV3 racing car with rack and pinion steering (where the angle of the 2 front wheels change instead of the 2 back wheels turning in the opposite direction to turn the car) When you use wheels it doesn't turn like when you use the other type of tires.
I'd like to use the remote that comes with the EV3 to do this, but I'm not sure how to modify the remote to support this type of control?

What EV3 model have you built, is it one of your own or one from the instructions provided with EV3?

The formulla race car

If I understand your question correctly, you are asking how to use the following remote to control traditional car that has front wheel rack and pinion steering rather than a vehicle that skid steers using the rear wheels. Here's the remote:

This isn't ideal for controlling steering because both sets of buttons point forward. The easiest solution is to attach a wheel on the side of the remote that actuates one set of controls like this. Here's an example using the PF remote that could be adapted to work with the EV3 remote.

I don't know what your vehicle design looks like, but you may also want some sort of return to center steering system on the motor controlling the orientation of the front wheels if you haven't already built one. Here's one simple example of this:

Its the remote from the ev3

Ah. Of course it is. Sorry about that. I've updated my answer.


text:
Questions about the company
I would like someone to answer a lot of questions  for a school project that i'm doing, if you can get someone to answer all these questions that'd be great.

What work ethic, qualities and attributes dose the company look for in their employees and why?
What academic skills do they want in their employees to have AND how do they use this on a daily basis?
What types of manufacturing equipment/machinery dose their company use most>?
What do each of these machinery do?
What training dose an enployee need in order to use the the equipment/machinery
What education is required for an entry-level position?
what education is required for a management position?
What is the salary (or salary range) for a management position?
What skills, benchmarks , or abilities are key to advancement from entry-level position to management level positions?

I'm voting to close this question as off-topic because we are not the Lego Group and some of these questions can only be answered by contacting them. Some of the questions might be answered by a google search though.

None of us on this website is affiliated with the LEGO company, so we can't answer these questions. You could, however, ask LEGO directly, via their customer service: https://wwwsecure.us.lego.com/en-us/service/

Most of these Exchange websites prefer one question per post.


text:
identifier expected?
What identifier is expected here?
#import "rw.txt" rw

task main()
{
    if(rw != NULL)
    {
        OnRev(OUT_A,75);
        Wait(100);
    }
}

Error: # Error: Identifier expected

I don't seem to be able to find a API describing the NXC API very well..

The error was caused because the file rw.txt was not uploaded to the nxt performing:
 t2n -v -put rw.txt

Solved the problem.


text:
Gearing down a PF XL
I'm looking for the best way to gear down a Power Function XL.
I need to achieve a very slow output RPM (less than 1-2 RPM). I've tried a 625:1 gear (trough 40:8 gear). Can someone link to a well done gearbox like that? Moreover, how I can make an axle more resistant at high torque (I've tried with brick round 2x2).

Do you mean less than 1-2 RPM?  As written, you're indicating greater than 1-2 RPM.

Yeah, I mean <1-2RPM (or around).

The XL motor runs at approximately 220 RPM.  Therefore, the following gearbox from the ELEC 201 class LEGO Design module from Rice should be sufficient:

You can use a worm gear for a compact, high ratio gearbox. By putting a worm gear on the motor shaft and using it to drive a 24 tooth gear you can achieve a 24:1 reduction.

For high torque applications you could use multiple parallel axles held together by gears or wheel hubs.

Sadly, a 24:1 doesn't resolve my problem. Maybe i can add some other gear using worm gear as the input.

Then by using two of these assemblies you can achieve 576:1 reduction. Or if that is too much, you can get another gear either before or after this setup for an additional 2:1 or 3:1 reduction.


text:
LEGO Technic part Numbers
My daughter got the LEGO Technic - Service Truck set. When we looked at the instructions, we saw a different notation on parts.
eg: the beams (cross beam) it has number 5 in white circle. what does that 5 stand for. Other instructions in same book have the number 3 or 7 in white circle.
Can anybody advise what these numbers mean?

Beams, axles, panels, and axles connectors usually have numbers next to them, to uniquely identifies the piece:

for beams and axles, the number is the length (length in number of holes)
for panels, it identifies the panel (and the panel mold contains the same number)
for axle connectors, it identifies the angle (again, the same number is part of the mold, and visible on the piece)

Same pieces with different colors have the same number attached

These numbers indicate the length of the beam or axle shown.
For a beam, this number is the number of holes it has. For an axle you have to hold it next to a beam and than count the number of holes.

Also, the instructions usually have a 'ruler' on that page of instructions so you can measure it even without a beam or brick of that length.


text:
Lego EV3 - Get output device type, opOUTPUT_GET_TYPE
I would like to know what kind of motor (XL, L) is connected to EV3 output port (A|B|C|D). I need to use direct command:
Instruction        opOutput_Get_Type (LAYER, NO, *TYPE)
Opcode             0xA0
Arguments          (Data8) LAYER – Specify chain layer number [0 - 3]
                   (Data8) NO – Port number [0 - 3]
                   (Data8) *TYPE

so request should looks like:
unsigned const char opOutput_Get_Type[] {
    0x09, 0x00, // bytes in message
    0x00, 0x00, // message counter
    0x00,       // DIRECT_COMMAND_REPLY
    0x01, 0x00, // 1 value will be returned
    0xA0,       // opOutput_Get_Type
    LC0(0),     // LAYER 0, first brick in chain
    LC0(0),     // port A
    GV0(0)      // returned value
};

When I send it to brick a get response:
04000000 0400
          ^-
          DIRECT_REPLY_ERROR

which stands that error occurred. Motor is connected to port A. What am I doing wrong?

Checking the source code, it appears that the opOutput_Get_Type command is not implemented. In both links, it is mentioned in the comments, but there is nothing in the actual code.
Unfortunately, I am not finding a different way to get this information.

Thanks for the tip. I've found command opOUTPUT_GET_TYPE = 0xA0 in bytecodes.h and parameters which it takes http://topikachu.github.io/python-ev3/OutputLibrary.html.

The one who wants to know device type should use direct command:
Instruction        opInput_Device (CMD, ...)
Opcode             0x99
CMD                GET_TYPEMODE = 0x05
Arguments
                   (Data8) LAYER – Specify chain layer number [0 - 3]
                   (Data8) NO – Port number [0 - 3]
Returns
                   (Data8) TYPE
                   (Data8) MODE - Device mode [0-7]

In order to discover all ports we should send
unsigned const char opOutput_Get_Type[] {
    0x35, 0x00,                                 //Message size = 53 bytes (0x35 hex)
    0x00, 0x00,                                 //Message Counter
    0x00,                                       //DIRECT_COMMAND_REPLY
    0x10, 0x00,                                 //16 values will be returned... 8 pairs (type, mode)
    0x99, 0x05, 0x00, 0x00, GV0(0), GV0(1),     //opInput_Device, GET_TYPEMODE, LAYER_0, PORT_A, TYPE, MODE
    0x99, 0x05, 0x00, 0x01, GV0(2), GV0(3),     //opInput_Device, GET_TYPEMODE, LAYER_0, PORT_B, TYPE, MODE
    0x99, 0x05, 0x00, 0x02, GV0(4), GV0(5),     //opInput_Device, GET_TYPEMODE, LAYER_0, PORT_C, TYPE, MODE
    0x99, 0x05, 0x00, 0x03, GV0(6), GV0(7),     //opInput_Device, GET_TYPEMODE, LAYER_0, PORT_D, TYPE, MODE
    0x99, 0x05, 0x00, 0x10, GV0(8), GV0(9),     //opInput_Device, GET_TYPEMODE, LAYER_0, PORT_1, TYPE, MODE
    0x99, 0x05, 0x00, 0x11, GV0(10), GV0(11),   //opInput_Device, GET_TYPEMODE, LAYER_0, PORT_2, TYPE, MODE
    0x99, 0x05, 0x00, 0x12, GV0(12), GV0(13),   //opInput_Device, GET_TYPEMODE, LAYER_0, PORT_3, TYPE, MODE
    0x99, 0x05, 0x00, 0x13, GV0(14), GV0(15),   //opInput_Device, GET_TYPEMODE, LAYER_0, PORT_4, TYPE, MODE
};

In return we'll get response i.e.:
13 00 00 00 02 7e 00 7e 00 7e 00 7e 00 08 00 07 00 07 00 7e 00

which stands (based on http://ev3.fantastic.computer/doxygen/types.html)
13 00   //message size = 19 bytes
00 00   //message counter
02      //success
7e 00   //nothing on port A
7e 00   //nothing on port B
7e 00   //nothing on port C
7e 00   //nothing on port D
08 00   //M-MOTOR-DEG on port 1
07 00   //L-MOTOR-DEG on port 2
07 01   //L-MOTOR-ROT on port 3
7e 00   //nothing on port 4


text:
Trying to get a modified traffic signal challenge worked out
The challenge is for a robot to go around the perimeter of a rectangular field and execute 90 degree turns when it gets within 4.5 inches of a wall.  Simultaneously, if the bot encounters a red flag, it needs to stop until the flag color turns green.  At that point, the arm holding the color sensor needs to dip to avoid the traffic signal, and once it is passed, continue on it's way.

I have tried running two threads, one where the bot encounters a flag (which I have constructed a switch for cases red and green), while the other is where it encounters a wall.  I think these two threads need to be encased within an infinite loop, but I can't seem to make it so.

You can use finite state machine. In this case you will have these 5 states:

RUN

Action: turn on the motors for moving straight
Transition to state TURN in case of event: ultrasonic sensor detects obstacle closer than 4.5 inch).
Transition to state WAIT in case of event: color sensor detects red color

WAIT

Action: stop motors
Transition to state CONTINUE in case of event: color sensor detects green

CONTINUE

Action: move forward a bit while avoiding the flag
Transition to state RUN immediately.

TURN

Action: Turn the robot 90 degrees right, increment the rotations
Transition to state STOP in case of event: rotations = 4
Transition to state RUN in case of event: rotations < 4

STOP

Action: Interrupt the program.
Here is the code I've just scratched without a testing, let me know if it works:

You can enhance the state machine to check for the flag during rotations, too. :)
You can learn this robotics topic from the great book by Daniele Benedetelli - LEGO MINDSTORMS EV3 Laboratory.


text:
How to program light sensor to follow moving light using NXT
Cannot figure out how to simply program Lego Mindstorm NXT robot to follow another moving robot that has a bright LED light attached to it.
Currently my programme looks like this:

It sounds like you are unfamiliar with how the light sensor works.  First off, it's not directional.  Secondly, it detects all light, including ambient light, so your LED may not be bright enough to even register on the light sensor.

A few things:  The light sensor has to be pretty close to something in order to be very functional.  How close will the other robot be?  How much ambient light would there be in the room?  Do you have more than one light sensor?  Also, you would probably get much more reliable/feasible results using an ultrasonic sensor.  Is there a reason why you must use light?

If I were you, I'd make it this way:
The leader robot has a very bright light shining backwards, but not in a tight beam, rather a wide cone, so it can be seen from the back easily.
The follower robot has the light sensor facing forward, with a cowl around and in front of the sensor in order to narrow its sensing angle. In other words, the sensor is modified in such a way that it only picks up anything if the light source is directly in front of it, not to the sides. This will help filtering out background "noises" (ambient light and other light sources).
Then the follower robot runs this pseudocode:
while true // enter stopping condition here if required
  while light is visible // current light value is over a threshold - experiment with this value
    go forward some amount
  // if light is not visible the while loop exits and we need to find the light
  store current light level to variable FRONT
  rotate 10 degrees to the right // experiment with various values, maybe less is enough, maybe more is needed
  store current light level to variable RIGHT
  if RIGHT < FRONT // the light probably moved to the left
    rotate 20 degrees to the left // twice the amount in the previous turn
  // else the light probably moved to the right, where we are currently headed
  // so there is no need to rotate further, just continue with the next iteration,
  // checking if we see the light now

This way the follower will go after the leader while it is headed in the right way, but when the follower loses the leader, it stops and turns around to look for the light.
This method however has a drawback. If the follower is slower than the leader, it will be left behind during the "stop and look around" phases, but if the follower is faster, it will run into the leader from the back.
You could remedy this by giving the leader a bumper on the back connected to a push button (pressure sensor), and program the leader to only move forward when something (probably the follower) has pushed into its back bumper.
Let me know if you need additional help.


text:
Trouble with Commander app: Using buttons to control motors
I'm having trouble with the Commander app for Android. I've put an EV3 into set 8448. I'm using one of the large motors for propulsion and a medium motor for rack and pinion steering. I don't have the remote (using the education set) so I'm trying to use my phone as a remote instead. I downloaded the Commander app.
I went into "create my own". I can use a slider to make the car go backwards and forwards, however, I tried to set up two buttons for steering, one button to make the medium motor go one way and another button to make it go the other way. Only one of the buttons works. It's only possible to make the medium motor go one way, not the other. How can I make it so the button controls can control the motor in either direction?
Any help would be greatly appreciated.

You cannot have more than one control per motor. If you have two controls, the signals are essentially sent to the EV3 at the same time, so only the second one will seem to work because it immediately changes whatever what sent by the first.
In your example, with 2 buttons, the buttons either command the motor to move or stop. If neither button is pressed, both are telling the motor to stop, so no problem. But if you press the first button, it tells the motor to turn, but the second button is telling the motor to stop. Since the EV3 got the message from the second button last, the motor stops and it appears that the first button does not work.
So, if you want to use the Commander app for this, you will need to use a different control that can turn the motor in either direction with just one control such as a slider or tilt.


text:
Representing pregnancy on LEGO minifigs without a dome
So far for pregnancy I have tried a fetal carrier that I put on the minifig's back but this limits her movements. Specifically she can't bend too far in either direction and also she can't lay down the way she normally would (she would have to like bend her legs when she lays down or something to keep the fetus inside).
My minifigs don't have a hole in the belly where I can put a big white dome to illustrate pregnancy.
So what is the best way to show pregnancy without a pregnancy dome?

I sincerely wish I understood what you were asking here, but I just don't get it. Are you trying to make a minifig look pregnant? I would generally ask for photos of what you have tried already, but in this case, I must admit that I'm a bit hesitant - I don't want to frighten the children! Please do clarify, what movements does the "fetal carrier" restrict (and what is one of those, anyway?) And why, oh why, did you put your the mother in a "pen" that looks like a jail cell? The mind boggles. :-) BTW Welcome to this site. I hope you find it useful.

This is the absolute strangest question I have seen here. I don't even know what to start. Fetal carrier, pen, jail-cell, pieces coming off violently during birth, pregnancy dome???!!! This makes me scared! :(

I have voted to close as "unclear what you're asking". Please edit your question to clarify and to provide more context.

What about using one of those pieces that goes over the head peg so you can attach a backpack, except hang it on the front side and attach a dome that way instead?

I've removed the elements of the question relating to the pen/crib as they don't seem relevant to the main part of the question. I'm assuming that you're also looking for a sort of "easy access display area" to hold this minifig which might be better suited to a different question.

Kit Z Fox, the neck bracket does not fit over the pants peg.

The best piece to represent a round belly is the "Plate, Round 2 x 2 with Rounded Bottom" (part 2654). The "dome" pieces are way too big. Connect the rounded bottom plate to the bottoms of two "Brick, Modified 1 x 1 with Headlight" bricks (part 4070), also known as the Erling brick. Use short legs to get the total height right.
Note that the pegs on the leg pieces are slightly larger than a normal stud, so they make for a very tight fit in the back of the Erling brick. They do fit with some force, and they are difficult to remove.
FYI, I experimented with a few iterations, including one using a 2x2 flat tile on a bracket, and this was the version that had my non-Lego fan wife exclaim, "Oh yeah, that looks good!"

This version cannot bend her legs, unfortunately.

One alternative is to use an appropriate decal rather than trying to construct something.

Image courtesy Flikr.

As far as I can see, most LEGO pregnancies appear to cheat, using glue or Blu Tack to attach the various elements on to the stomach of the minifig.
One example I've seen is the use of a 1x2 tile, as seen here at the Brick Testament:

In this image, Mary could be holding the tile in place, but in other images, her hands are not near enough.
Also to your point of lying down - in real life I've noticed that some pregnant women prefer to lay on their sides rather than their backs, certainly during the later stages of pregnancy.

I can't get neck brackets to fit over the minifig hip studs.

Hmm, curious I'll have another go - I'm sure I've done something similar in the past...

They do not fit. The leg pegs are slightly larger than a stud. (This is also why the use of slopes as skirts results in a loose connection.)

I usually hang the minifig back plate with knob on the front with a dome, or I use two between the torso and legs (they will fit) and attach a dome or something else.


text:
Issues connecting the EV3 on Windows 8.1 64bit
I have got a computer with Windows 8.1 64 bit and I have installed LEGO Mindstorms EV3 software Home edition and tried to connect the EV3 brick to the computer, but the brick didn´t connect to the computer. Where is the problem?

Did you try USB or Bluetooth or both?

OP's not been back to this question and there are open questions about the problem.

I'm going to assume this is a Bluetooth connectivity issue because connecting the cable is trivial, and I've found connecting with Bluetooth quite tricky.  This may not be the only way, however it has worked for me.  The main issue is that you first need to "pair" the EV3 with your computer.
Setup (you have Bluetooth, and it is turned on):

Make sure the computer has Bluetooth turned on.  On my Win8 computer, there is a Bluetooth icon on the task bar when it is active.  If you don't see that icon, or don't know if Bluetooth is on, go to: PC Settings > PC and Devices > Bluetooth (also under: Network > Airplane Mode.  If you can't find it, try searching for Bluetooth on the computer)
set the EV3 to have Bluetooth Visibility checked true.  This is under the tools tab (far right) on the EV3.  Move the cursor to the Bluetooth line, and click on that to see the Bluetooth details.  Both "Visibility" and "Bluetooth" need to be checked on boxes on the right (ignore the icons on the left, they look like radio buttons but are not).  Once those are checked, the EV3 will be visible to the computer's Bluetooth.

Once you've confirmed that visibility is on, and Bluetooth is working, there are a few different ways you can pair your computer with the EV3.

from the computer's Bluetooth software
under the Control Panel > Devices and Printers, you can "Add a Device"
from the Bluetooth Icon on the task bar ("Add a Bluetooth Device").

No method is better, whichever you find first.  Once it starts scanning, it should display the EV3 within a minute or two.   When the EV3 when is found, choose "pair" or "connect".   Now, switch to the EV3 which should display:
"Connect? (your computer's name)"

Move the cursor to the check box (default is on the "x" as in "No"), then you will be shown the passkey: 1234.  No need to change that.  Click that check box too.
Now, switch back to your computer, where you'll be prompted for the passkey.  Enter 1234, and it should complete the pairing.   If you are interrupted (I believe you have 2 minutes) it'll lose the connection and you'll need to start again.
After all of that, you should be able to start the Mindstorm software, open a project, and in the lower right, choose "Available Bricks" tab, and see your EV3 (if not, click the "refresh" button in that window and it should show up).  Once there is a check box for your EV3, click that box to finally connect.
The hard part is the pairing.  Once paired, it is simple to connect in the future.  I just make sure the EV3 is on before the Mindstorm software is started.  If the EV3 is turned off, I have to click that "refresh" button telling the computer to find it again, then check the box to connect.
Final note: on the Bluetooth menu of the EV3 (where you check Visibility), there is another item "Connections."  This isn't merely a title.  Click on this, and it will display all computers that it has paired with in the past.  You can click on these and have them removed.  I've had to do this occasionally to re-establish connection with a computer.  This is how you would remove old connections too, if you wanted to clean things up, or just want to make sure there aren't any left-overs from earlier connection attempts.

Make sure that the robot is actually on: it's a simple mistake but one I've made more times than I can count! If it's via USB, make sure that the USB port and the wire are both working. If it's bluetooth, similarly make sure that both parts are working correctly. Hopefully this helps!


text:
Is there a LEGO clamping tool?
Sometimes we cannot easily attach 2 LEGO pieces.
Is there a tool to help clamp together LEGO pieces that are very tight?

I agree that sometimes adding smaller plates can be tricky - the issue is usually caused by misalignment of the studs and holes.
You could use one of the Brick Separators in reverse (i.e. add the brick to the separator and then attach it to the other part), or you could try adding a larger brick first temporarily to help you line up the piece.
The other elements that we have trouble with are the hinges and clips, and for that I've found just taking your time and easing it gently is the best option.

Agreed. Most of the time alignment is the issue, and clamping pieces will just break them.

If you’re using regular bricks and plates, there is really no sure way to tightly lock them together. The only way to ensure secure assembly is to use special or Technic pieces.
If you use special bricks with “knobs” separating each row or layer with two rows or layers of plates, you can then use plates across the knobs.
A more secure assembly would be to use Technic bricks with connector pegs, separate each row with two rows of plates and use Technic beams across the connector pegs.
If you have a wall structure that is two units thick you can also use bearing elements which are 2×2 bricks with snaps.


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Cracked LEGO torso
I recently discovered that my LEGO Legolas minifig from LEGO Lord of the Rings has two small cracks starting from the base of the torso on each side, but I wonder: will these cracks extend and damage the fig?

"LEGO Legolas" makes me chuckle every time.

This is fundamentally the same as Minifigure Torso Cracks. While waiting for your replacement, you may find the answers to Repairing LEGO minifigure torso damage helpful to minimise further damage :)

LEGO Legolas's lass lets LEGO Legolas lasso lots of LEGO lasses.

These cracks will often get worse over time as the legs are removed and replaced, or simply from normal play. Even if they don't get worse, the legs probably already have low clutch power which may be causing the legs to simply fall off.
Given that LEGO is still producing a Legolas minifig, they will almost certainly be happy to replace that torso for you. You can either find the piece that is broken and submit a replacement request to LEGO, or you can contact customer service directly and explain which piece is broken.

This really depends on how much you plan to use LEGO-las. If he's to be used just as a display or collectors item, he should be fine; to ensure safety, super-glue the poor elf's pants to his body.
If you plan to make him hop around and destroy orcs on a regular basis, try super-gluing the cracks from the inside while the pants are removed or it will get worse.
If the crack is too small to super-glue, I wouldn't worry till LEGO-las' legs get loose, which will happen if he is excessively used for play.


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Can I Conect 2 NXTs so that they work together?
I am building up a robot and I want to use 2 NXT connected together because I need more than 3 ports A,B,C. So my question here is: When I write the code, is there anything different I have to do?
For example do I write the same code I would use for 2 NXT and just connect them together or do I have to do something more than this?
I found a way to connect them but I have not found examples yet of the blocks (nxt code software).

You might also find How can I use more than 3 motors with one NXT brick useful :)

Without 3rd party hardware or software, the only way to do this is to use Bluetooth messages. For example, you could write motor power to a Bluetooth mailbox on one NXT. The other NXT just has a simple program with a loop that reads the Bluetooth mailbox and connects it to a motor block.


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What's an effective strategy for purchasing large numbers of different bricks?
If you want to go on bricklink for example, you search by part but the end up with parts on various different stores. Buying on ebay is extremely expensive for groups of different parts. How do you deal with it?

Welcome to this site! I hope you don't mind, but I've edited your question slightly to make it slightly less subjective, and therefore a better fit for this site.

On bricklink, your example, if you input the parts into a wanted list it allows you to find stores that have all (or most) of the parts on the list letting you minimize shipping costs.


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Microsoft Robotics Developer Studio & RCX Support?
What is the last version of the Microsoft Robotics Developer Studio that supports the RCX?
The Wikipedia link (http://en.wikipedia.org/wiki/Microsoft_Robotics_Developer_Studio) indicates RCX was dropped in the "latest" version but doesn't indicate what version.

I'm not an expert on Robotics Developer Studio, but the phrase indicating that support was dropped in the latest version was added in July 2008, so you'll need to go back to version 1.5 in order to have RCX support.


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I have an idea for a new kind of LEGO, using new types of elements
I have an idea for a new LEGO product (not a LEGO set or anything, I know that the Lego ideas site exists, but a new "kind" of LEGO)
I've been trying to contact LEGO about it without any luck.
So I thought I'd give this site a shot as well since I think the idea has a lot of potential.
Now to the question. Is there any way I can contact a LEGO designer or just anyone at LEGO to pitch my idea to?
Or should I just give up?

We already have some pointers for contacting a designer and it's been pointed out that LEGO don't really take suggestions for new products other than through Ideas.

Re-opened as the duplicate suggestion recommends using ideas, and Oskar's aware of that and that's it's not really appropriate.

If the idea is a new kind of part, element in plastic, you may want to take it into your own hands and try to design it in a free cad app (like Sketchup, Open SCAD, Creo Elements or something). There are people around here (like myself) who have 3d printers, and may be able to suggest or try things out. You can then see if there is a market for such Lego compatible elements - see who else is interested.
Lego are unlikely to take these kind of risks themselves, but there are resources for people to try new things themselves.

This.  You almost never will get traction with a major corporation about adopting your (significant) ideas (because, among other reasons, they'd have to pay you for them - even if you don't want payment); but there's nothing special about 'plastic blocks' such that you couldn't make your own competing (and, more importantly, compatible) product, and then perhaps eventually Lego will see your idea and either make their own, or buy your idea/company.

I'm not entirely sure which direction you're going in for the "new 'kind' of LEGO - but as you point out, unless this is based around existing LEGO elements Ideas is probably not for you:

Your models may only use existing LEGO parts. We do not allow suggestions for new LEGO parts.

So unless it's based on System (and by extension Friends and Elves) or DUPLO you're probably out of luck there - from an older Cusoo FAQ:

Models should not depend on new LEGO element molds. While we love considering new elements, if a model depends on a new element, there are more potential factors on which it can fail review. [...] An existing element in a new color is OK, but a new element in one set isn’t likely.

You might get some traction through the Marketing teams, as product development comes under the "Marketing and Products" division under the CMO - for example the 2011 edition of "The LEGO Group - a short presentation" talks about there being a number of "product development deparments", while the 2014 edition shows "product group 1" and "product group 2" and both state that:

Concept and product development takes place primarily at our Billund headquarters in Denmark. The LEGO Group also has a listening post in Los Angeles to help monitor the
  latest trends.


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EV3 FLL Question " outside the box "
I am joining our FLL team and I have a question can you please help me?
I'm working on the mission "outside the box" and my arm on the robot is not strong enough to lift the box in the air, so that the block in the box will fall out.
How can I make my robot arm stronger so that I can lift the box in the air?
Can it be that we have to place the with the gear on another place? for example: the big gear on the right side and the small gear on the left side or the other way around?

You'll need to clarify some things.  First, how are you powering your robot arm?  What gears are you using?  Have you tried other gear ratios to increase torque?

Similar to: How can a lego-mindstorm robot lift something very heavy

Are you able to provide some pictures of what you've tried so far?


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9398 problem with the front wheels
I've just finished 9398 4x4 Crawler. The rear motor works properly, but the front motor doesn't: The wheels seem to be locked, although they spin freely when I turn them by hand.
What could be the problem?

In my version of the set, there is an extra sheet pointing towards this particular piece. It is not a mistake in the instruction, but they put in an additional picture to clarify how it is done correctly.

Check if Cross Block 90° that is placed in step 53 of instruction book 1 is in the correct orientation with the round hole placed over the motor axle.
Mounting it the other way will prevent rotation of the motor.

YOU DID! Solved! One piece in a wrong position and everything locked. Thanks a lot!

@Cezar Then you should also mark this answer as the correct one to give Joost proper credit!


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8258 Headlight assemblies
Anyone else having a problem with with headlight assemblies on 8258 crane truck?  I can't seem to fit them in due to interference from fog light bar. Thanks

I never noticed any problem with it. Do you have a picture of your model.

From looking at the picture, it appears as if there is a brick (a 1x2 brick, light gray) behind the headlight. The headlight connects to it in a similar fashion as shown in the following image:

Hopefully that helps.


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Programming the LEGO Mindstorms T-Rex
I followed the instructions up to the MoveAbsolute My Block for the T-rex but I'm not able to link the last connection (Brake at End). Can anyone advise what I might need to change?

Are you referring to the EV3 T-Rex from The LEGO MINDSTORMS EV3 Laboratory or a different robot?

I'm referring to the EV3 T-Rex from Lego Mindstorms EV3 Laboratory from Daniele Benedettelli.


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Light on color sensor is blue
We had the sensor color on red and it was working with our remote.  We changed the batteries in the 'brain' and now the light sensor is blue and won't work with the remote.  Any suggestions? It's a mindstorm EV3 sensor.

The color of the LED on the LEGO EV3 Color Sensor depends on which mode it is in.
From the EV3 help file:

COLOR MODE

When the Color Sensor is in Color mode, red, green, and blue LED lights on the front of the sensor will turn on.
REFLECTED LIGHT INTENSITY MODE

When the Color Sensor is in Reflected Light Intensity mode, a red LED light on the front of the sensor will turn on.
AMBIENT LIGHT INTENSITY MODE

In Ambient Light Intensity mode, a blue LED light on the front of the sensor will turn on dimly.

If you want the LED to be red, make sure you are using the Reflected Light Intensity Mode in your program.
If you are doing this and the LED still does not turn red, you should contact LEGO MINDSTORMS customer support.


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What is the biggest LEGO-compatible one piece wheel?
I am wondering what the biggest LEGO one piece wheel is? (the inside part and the rubber part counts as one piece in my world)

See also the related question: What are the largest Technic-compatible tires on the market? - although that is specifically asking for tires.

Am I the only one that noticed they never specified Lego wheel?  I think some absurd answers are in order. ;)

I noticed. I also noticed your answer. ;)

@Zhaph-BenDuguid, Thank you for removing my post from this thread. I agree it was not on topic. I am new here and will not do it again. Also I apologize for using a comment to respond but I cannot figure out how to send a message to another user. I am really new.

Well, got a few laughs out of it before the edit.  Harmless fun, apologizes for any feathers ruffled.

@Dan1138 JohnnyB no problem either of you - while a bit of fun is always appreciated, if it can be in the context of an on-topic answer that would be great. Otherwise we'll just end up with joke answers everywhere ;)

Pretty sure it's Hailfire Droid Wheel.

Confirmed, though it is missing a center hub and is thus difficult to use. The next in size that does have one is 59521 http://www.bricklink.com/catalogItem.asp?P=59521


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Bluetooth Conection PC-NXT1-NXT2
I want to connect, via Bluetooth, one PC with a NXT brick and then have that NXT communicate with another NXT.
So I send a message from the PC to NXT1 and have NXT1 send a message to NXT2.
Is this possible?

https://bitbucket.org/Thad_Hughes/cortex/src
Here's something in NXC and python that routes from NXT1 to NXT2 through the PC; emulating a non-master/slave config between all three devices. Has the added benefit of a seamless pairing method.
It could be helpful to give a little more detail (what languages you are using, what direction(s) of communication you desire)...

Yes it is possible. You just need to write a program for NXT1 that forwards the messages from the PC to NXT2.


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Connection between two NXT bricks
Is it possible send information from BrickNXT_A to BrickNXTB_B?
For example I have a touch sensor connected to IN_1 of Brick_A and I want send the result of the sensor status (1 or 0) to Brick_B. If the touch sensor status on IN_1 of brick_A is 1, then the motor connected with OUT_A in brick_B, turn for 1 rotation.
How to do this with NXC? My difficult is the connection and sending information between the Bricks.

A long time ago in an university club we once managed to hack an RCX cable into an RCX compatible LED, built a frame to mount it into a LEGO structure, wrapped a clear flexible plastic "wire" in tinfoil and duct tape (to minimise light loss) and built another LEGO structure for the other end that held an NXT light sensor. After a bit of programming we could send information from the RCX to the NXT via the optical cable. the only downside was the speed: we could only manage about 1 bit per second. Maybe someone could improve on this concept?

Yes, it is possible. Have a look at the "Comm module functions" section of the NXT help file. For example, since the touch sensor status is a boolean value, you could use the SendRemoteBool and ReceiveRemoteBool functions. You can communicate wirelessly using the Bluetooth functions (BT*) or you can have a wired connection using RS485 by connecting input port 4 on each brick to each other.


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How to Return a Motor to a specific value
I've created an arm robot using Mindstrom NXT that can find an object pick it up and move it to an new and random location. My problem is that I would like for the motor to, at the end of the program, return to the position it started at. The random movement of the arm and how to program it to move back to the starting position is the cause of my confusion. Can anyone give some suggestions or a solution as to what I should do?

This is fundamentally a variant of How to remember initial position of a robot and return to it and Return a robot to it's start position...


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Access hatch in a wall?
Working on a 10 stud by 10 stud Square bell tower for my annual project. Need to create a access panel/door. Any tricks that can be done so it's hidden or at least not easily noticed?
I need to hide a small MP3 player and speaker inside and need access to the player to turn it on and off.

This is a hatch so that you can get at the inside of the tower, rather than a "hidden" hatch for a minifig?

It may even be easier to build your tower so that the top part of it can come of (resting on tiles on the lower part with maybe 1-2 studs to hold it in place), then you can access whatever you need by simply removing the top part. And, you can have additional layers if required.

The idea is to hide a small MP3 speaker inside. I just need to get access to it and the player so I can turn it on.

Then I'd say the removable top is really the easiest to work with.

I would suggest not using hinges of any kind, but just making a plain panel with a tile on top, resting on a tile in the wall. For an example from LEGO itself, have a look at booklet 2 of the instructions for set 7094 King's Castle Siege. Notice they use panels instead of flat tiles which is even less visible from the outside (although they did it not for that reason but to make sure it was easier to remove).

In your case, you'll want to block it from behind (with slopes at each corner for example) as you don't want it to go into the structure.
To remove it, you'll either need to draw it by some protruding fixture if you can fit one in, or push it from the inside by another mechanism (for example, pushing on something on the top would activate a lever which would push the wall)


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Waterproofing LEGO bricks
I have a LEGO ship that I want to photograph as it's sailing along in a pool. Of course the LEGO bricks have cracks in between them so water will leak through.
Does anyone have any ideas as to how to waterproof the hull? Something that won't harm the bricks that can be easily removed. Also I don't want whatever the material is to be visible in a photo.

Are you going to build something like this?

Holy smokes! I've got a Lego pirate ship (it's my brother's actually). It's the Black Sea Barracuda.

I would try liquid latex (liquid frisket) which you can buy in most art supply store.
This will not damage the bricks and is easy to peel off. You can apply it using a cheap throwaway brush, either in between the bricks (like a cement wall) or as a thin transparent layer on the whole hull. I recommend the second method because it's fast, straight forward and the easiest one to clean up.
I use this stuff for all kind of painting and molding jobs. It's a great material.

I use liquid frisket for art too.  It's an excellent suggestion since it is easy to come by and also removable.

I would tend to suggest another non-waterproofing solution - build something to hold your ship from underneath, that will safely rest on the bottom of your pool.
Of course, if you don't want it to show on the picture, you'll have to be extra careful about how you do it, but I think it's the simpliest solution.
What I would do is buy a large plexiglass sheet (or any other transparent material), make sure your ship is secured to it (drill some 8mm holes in the plexiglass and poke studs in them, or Technic Axles, or whatever). Then you can have someone hold the sheet & ship slightly under water so that the ship looks like it's floating, whereas it's actually not. As long as the borders of the sheet are outside of your camera frame, you're in business.
I owe that idea to a Stargate SG-1 episode I rewatched recently, actually. In the making of, they explaing how they make it look like a bullet is floating in mid-air - they just embed it in a plexiglass sheet and film right through it. It's it's good enough for commercial television, it should work for you too.

Maybe you don't need to waterproof it. If you are able to fit a block of foam (eg. extruded polystyrene) inside the hull, that will probably be enough to ensure buoyancy.

I suspect that water leaking through the hull will not be the real problem you need to solve. Granted, I haven't seen a photo of what you have built, so I might be wrong. I think the real problem you might have is that a Lego boat will be quite a bit less massive than a wooden or steel ship with the same proportions.
If you go look up some of the old sectional boats that they made in the mid 1970s, they all came with lead filled keel piece to keep the otherwise light and rather top heavy Lego boats from capsizing. Depending on your weight distribution, you might need to add some ballast to keep it floating correctly. If you aren't up on your boat physics, just keep the center of mass of the boat as low as possible in the water.
I suggest you give it a 'dry run' (ha-ha, get it?) in your bathtub and make sure that you aren't accidentally going to recreate the closing scene of Titanic before you set up your photo shoot.

Try spraying the inside with plasti dip, it goes on like spray paint or you can use a cheap paint brush, then you can peel off as one whole piece. Best of all it comes in many colors!
Get it here www.plastidip.com they also sell it at most home improvement stores.

Maybe clear contact-paper on the inside?

Put tape around it. Make sure to duble layer it.

You could use cling wrap, or plastic wrap might work. Maybe you could use aluminum foil.

Hello Tanners, can you add some more details or photos of your method? This question is quite old and there already are some answers. Personally, I can imagine that the cling wrap could work, but it will be visible, won't it (see question)?

I'd suggest to use clear silicon to seal the underside of the hull then add a weight in the bottom middle to keep balance and also make the ship a bit heavier.
I didn’t try this but it was my best idea.


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What is the brown ship in the Star Wars 2012 advent calendar?
The brown boxy ship is shown in the ad, but I have no idea what it is? My son was waiting all day for me to get home and tell him, but I can't figure it out!

According to BrickLink it is a Trade Federation MTT

Same on Brickset, according to which "we can all see it's an MTT". I'll be honest, I don't who "we" is, but it sure doesn't include me either.

It seems to be a Trade Fedration MTT from episode III.

Welcome to the site. This answer does give a lot of information (The relatively short answer from McKay already refers to the same vehicle with more details and links).  If this is your first time on a StackExchange site I invite you to read the FAQ (link at the top right). This will show you how you can ask and answer questions.

Comments are not for extended discussion; this conversation has been moved to chat.


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I have entered codes for days 1-7 on the LEGO Star Wars Calendar site and now can't enter any more
I have the LEGO Star Wars Advent calendar and have put in the codes up to day 7, however it will not allow me to proceed and put in any more codes from day 8 upwards - are other people having this issue? Can I only "open" so many doors in one day?


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What are Good LEGO (or similiar) sets to play-prototype machines working with fluids?
I want to play around with fluid engines.
I'm aware that LEGO is sometimes used in labs for prototyping kinematic components, are there successful examples of operating with fluids?
Have pistons, pipes or other conduits, valves and maybe turbines been built with LEGO?
With what components?

There are a number of Lego Pneumatic sets with airtight tubes, valves and switches which could be put into use with fluids. One is 9641, Pneumatics Add-On Set.

Bear in mind that the pneumatics sets can command a much higer price than those sets with a similar number of parts, and buying individual pieces can also get expensive. Have a look at BrickLink to see what parts are avalible.
There is also a Simple & Powered machines set which comes with sails that could be used as a wind turbine, or a basic pump, but if you wanted to use steam or liquids with Lego you would have to be very careful.
A company called LPE Power has made some very detailed and very powerful pnuematic engines however I doubt they would work with water.

The Lego pneumatic valves are not great for (liquid) fluid experiments as the valves dissipate the return path to atmosphere, so they p*ss water out. And the pneumatic hand pump spring and metal core of the regular pistons rusts in a few days. It's about 15 years since I learn't this :-)


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What's the thing between the pant legs?
What is the piece that holds the pant legs together called? Is there an "official1" name? Or is there just a commonly agreed on term?

1Official meaning something mentioned, even in passing, by Lego in some way.

They are referred to as "Minifig Hips" almost everywhere: [partlink:970:4].
The LEGO Pick-a-brick service doesn't sell them without legs, and just refers to the whole construction as "Mini Figure Mini Lower Part":

Since that's utterly boring, I suggest we just start calling the thing what it actually is: a thong. Or a speedo.

@Joubarc Like the Beach Troopers from the LEGO Star Wars games?

And surely it's only a thong/speedo they are a different colour from the the legs, otherwise it's just waistband and flys/hips.

I just call it a belt

I once used the hips as rollers in a set, they look a bit like that with legs removed


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How do I unlock the daily surprises?
I got a lego star wars 2012 advent calendar (9509), and on the back it say "unlock a surprise every day", and it says to go to legostarwars.com, and there's a code on the back of the advent calendar flap, but when I go to legostarwars.com, it redirects(?) me to a lego star wars III clone wars game experience, and I don't know where to enter the code. Where am I supposed to enter the code?

The durability of LEGO products usually outlasts anything they do digitally, and this is no exception - as of april 2013, the action has long ended and the page to enter the code doesn't exist anymore. As such, this question isn't likely to help future visitors, hence the closing.

That is not the URL you're looking for ;)
Apparently you need to enter the codes on the LEGO.com Star Wars Advent Calendar page.

The codes are:
obiwan:MYONLYHOPE

GREEDO:HESHOTFIRST

HAN SOLO: NERFHERDER

leia:YOURWORSHIPFULNESS

VADER:MOSTIMPRESSIVE

SIDIOUS:DARKSIDE

LANDO:CLOUDCITYGAMBLER

BOBA:SARLACCFOOD

LUKE:KISSEDMYSISTER

CHEWBACCA:LETTHEWOOKIEEWIN

SAVAGE OPRESS:OPPRESSIVEMAUL


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Are the blue and grey 12v train system compatible?
Are the two generations of 12v train compatible?
Eg can you combine a "blue" remote controlled point and a "grey" 12v transformer?
Main motivation for this: I have a complete "grey" set of trains, tracks and accessories and "blue" items are much much cheaper on the re-sale market, so I'd rather buy additional "blue" items.

It's more or less obvious that tracks themselves are compatible, although blue rails won't go on dark gray sleepers, which isn't really a problem. You may want to use more sleepers under blue tracks to stabilise it, although the 12v inserts help. Mixing blue and grey track and inserts shouldn't be a problem, should you wish to do so.
Motors are also compatible and pick up power the exact same way. Cables use the same connectors and are thus compatible too (if you want to add lighting to your trains).
As for accessories, I can't be sure but I believe there are limitations. If you look at the blue transformer, you'll notice the output to remote control the switch is 16v AC, while grey era remotes use 12v DC. Feeding 12v remotes with 16v might work (it's just an electromagnet inside and shouldn't be exposed for too long), if the blue era remotes need 16v, they may not work with only 12v.
Moreover, the wiring is also different: 12v era remotes use a standard cable, and the polarity determines the direction you want to turn it, but the blue era points use a 3-wire cable, as evidence by this extension cable. And let's not forget the difference AC/DC, which mean you'll have to add some non-LEGO components to make it work.
In short, I think controlling 12v era remotes with the blue transformer should be easy (a couple of diodes should do the trick), but the opposite might prove tricky, and if you have blue points, you may want to get a blue transformer as well. (Then again, I don't know enough about electronics to know how tricky it would be).
A small caveat though: I assumed you have the blue point without the remotes themselves, but since they were sold together, it could be that you get the point, wiring and remote together. If that's so, you best bet is to use the 12v AC output of the 7864 transformer - maybe that's its purpose (and if you try that, and it works, please go answer that question).

Thanks for covering all the aspects (tracks, motors, remotes).

The answer is yes.
Using the 13v~ (alternate) output of the grey line transformer you can command the blue line switches.
This is not in the manual of the new transformer (it is a kind of hidden door to the past) and the blue line transformer switches output was 16v~, but I've tried it and it works.

I just got some blue era stuff.  I'm going to try and see what happens, but the grey era Transformer has >13V output and I think that is legacy for the blue track stuff.  So that you can plug in switches to there (until now I've wondered what on earth that output is for!!)

Did you managed to discover the intended use for the 13V output? More important, did you discover if the blue train switch can be used with the gray transformer?

@PedroQuaresma I've moved your answer to a comment here, but this user has been inactive for several years, so you are unlikely to hear back from them. You might be better off asking a new question such as "Can the 13V output on the 7864 transformer be used to support blue-era points?"


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Are third party NXT compatible parts safe to use?
I bought the Mindstorms NXT for my son's coming birthday and I noticed that there are several places you can get third party parts to use with it (sensors, connectors, etc).  Are these safe for the NXT brick?  Has anyone had any problems using these?
If they are ok it's a great way to expand our capability but NXT is a big investment and we don't want to risk ruining it.

The majority of sensors manufactured by HiTechnic (a third party company) are certified by The  Lego Group. The company's website lists the following criteria required to be certified:

100% compatible with Mindstorms NXT
Meet the highest LEGO quality standards
Comply with all safety standards
RoHs Compliant (certified lead free)

These sensors are manufactured by HiTechnic and approved by Lego are sold in the Lego.com Shop:

#2852724 Accelerometer
#10285 Compass
#2852726 Gyroscopic
#2855040 IR (Infrared) Receiver
#2852725 IR Seeker
#2853216 IR Link

Sensors and custom parts are generally expensive. The sensors above range from $54.99-$49.99 so it would be worthwhile considering the value of the sensor before you decide to make a purchase.
I would recommend judging the sensor(s) by their expected frequency of use, the potential for sensors to be used in other creations and their level of experience with the Mindstorms NXT system.

Thank you, it's good to know HiTechnic is certified by LEGO. Are they the only third party company certified by LEGO, or is it standardized that if you make NXT compatible parts you have to be certified by LEGO?

@LynneaTaylor As far as I'm aware HiTechnic is the only certified manufacturer for Lego NXT Sensor products.


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Removing glue from Lego bricks
When I was five my Dad used some kind of a good glue to put together a set together so I didn't loose any pieces. Putting the ethics of that action aside, I want to split the bricks from another and remove the glue. I tried heating up the set in boiling water but the glue didn't budge. Any ideas out there?

Unfortunately, knowing which kind of glue was used might be a crucial piece of information. And some may be impossible to remove altogether (Methyl-Ethyl-Ketone like they use in LEGOland parks, for example, as it fuses bricks together)

See also this answer regarding glue.

And why do we even have a tag [tag:glue] anyway?

Don't remove the glue at all. What your dad glued up back then is now a relic.

Tough job.
You can try using some nail polish remover to try to start breaking down the glue.
From Removing Super Glue, which they give for advice for people that accidentally glue their fingers together, this procedure might also work for the bricks.

...even though Super Glue is incredibly strong, it has one weakness: acetone.
Acetone is often found in household nail polish remover, and a small amount on the end of a Q-tip or cotton swab applied directly to the glue should dissolve the bond without damaging the skin.

A lot will depend obviously on how much glue was used inside the bricks, but perhaps a little crack and a small screw driver to help pry them apart and keep applying the acetone to the reachable edges can help break them apart.
I don't know if acetone will do something to the brick's color or structure, so proceed carefully.
Good luck.

Yes, be very careful with acetone as it's been shown previously to ideal for melting bricks together

@Kaylee yes, for images look towards the end of the this article

Well, maybe you could try using a nail in between the bricks. I personally have never glued legos together, so I am just giving an idea. Odd, right?
Good Luck!

Non acetone nail polish remover is used to remove glue and polish bit notnharm artificial nails. It's used tonremove pitch from cars without harming paint. After reading this, I guess it's about my only hope.


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Is it possible to obtain a replacement part for a collectible minifigure?
My son's latest collectible minifigure purchase was missing its legs.  Is it possible to get a replacement set of legs?

I had a part missing from a brand new Cars lego set (old set but bought brand new at retail and unopened). Lego wouldnt provide the missing part as they said they no longer produced it. I eventually managed to find the part on eBay (albeit second hand and not cheap, although mint condition)

In short, yes it is possible.
The best place to find replacement parts is Bricklink.com.
You don't mention which minifgure is missing its leg, but for example, here is a link to the 'Hips and Legs with Studded Belt and Safety Pins Pattern' of the Series 4 minifg 'Punk Rocker'.
To find the required part for your minifig, a good starting point would be to look thorough the Collectible Minifigures Catalog Gallery on Bricklink and go from there.
As for cost, it varies greatly on based on rarity and desirability of the part you are looking for.

LEGO will replace a part for free on their website, providing it was missing from purchase. Sadly replacement parts aren't available for Collectible Minifigures, but you can contact them to let them know.
Ensure the Minifigure packet has been fully emptied, it's quite easy to lose parts when you open the packet.

+1, Lego is very good about providing replacement parts for pieces that were missing from a newly purchased set.

@JW8 True, but I did try using a set ID from one of the minifigure packets on the part replacement site but they don't do replacement parts for them.

got it - I've never replaced parts from the minifig packs before, only the usual sets.


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Why do the tubes in the Seattle Space Needle Architecture set need to be cut?
I just received the Seattle Space Needle from the Architecture series. There are tubes that the builder is required to cut to a certain length for the model.  This is the first time I've encountered tubes in a LEGO model.  Are the tubes made only one size making it normal to have to cut them to use them?  I was wondering why the tubes were not manufactured to the correct size instead of having the builder cut them.

Why do they need to be cut? Duh, because they would be too long otherwise.

Well, I guess I could have gnawed them instead, LOL.

This happens in Technic models as well, at least for pneumatics tubes. I would tend to assume it's a simple production issue or simplification - as this requires less work from LEGO.
That way, they only need one length of tube per model, instead of having one part ID for each of length of tube. Considering LEGO wants to control its number of elements currently in production (it's not infinite), this makes sense.