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Can using a hex key to disassemble LEGO Technic pieces cause damage?
Does using the right size hex key (Allen key) to speed up the disassembly process cause damage to the LEGO Technic pieces?

In my experience, growing up with them, you can always make a Lego disassembly tool out of more Legos, and then take the tool apart.  You might need to be clever with some of them, but there is always a way.  And you don't risk damage by using a harder material.  You can still bend things though, or break them if your tool isn't designed very well and you use too much force, so you need to be careful with that.

Yes
A hex key, being tough metal, is inherently a danger to ABS plastic. Using it to push axles and pop connections will eventually scratch and wear down your parts, something you don't want with technic pieces.

Having used small pliers to get axles out, we should really come up with plastic tools to solve these problems.

@tl8 what are you trying to get the axle out of? Lego have a tool for taking elements apart that includes a stub of axle for pushing them through. The limit tends to come attempting to get an axle-connector or 2-axle out of a dead-end element.


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Is it possible to build a steering system without using gear racks such as part 87761?
Is it possible to use part 6575 (and together with other Technic pieces) as an alternative to part 87761 for a steering system? (I am trying to use Technic pieces from Technic 42030 set to simulate this MOC). If possible, how do I go about it?
Part 87761

Part 6575

To be honest, these parts don't seem to have anything to do with each other. You may wish to have a look at another question dealing with replacing 87761: http://bricks.stackexchange.com/questions/2771/alternative-for-technic-gear-rack-1-x-7-with-axle-and-pin-holes

What specifically are you trying to design? If you're trying to do something specific with the gear rack (e.g. create a steering system), we might be able to help you come up with alternative designs, but without knowing that, it's hard to see how the two parts you mentioned would be replacements for one another.

@jncraton, Thanks for the feedback, I have added my specification to the question.

It's possible to build a steering system without using a gear rack. Rack and pinion steering is simply one of the easiest ways to translate the rotational motion of a steering wheel to the translational motion needed to adjust the wheels.
Here's one example of using tie rods and a knuckle to accomplish steering:

That's obviously quite complicated because it incorporates suspension as well as steering, but it's too pretty to not include. This basic concept is what is often used on go carts because it's dead simple, and mechanical advantage isn't very important on vehicles that small:

This design can be simplified to not need ball joints as long as all the moving parts stay in the same plane. Here's an example of Ackermann steering implemented that way:

You could swap 6575 into that design instead of 2825 pretty easily.
Here's an even simpler example with a motor mounted perpendicularly to avoid even needing to use any gears:

You can even use the requested part 6575 in your first design

source: Stack Exchange

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

sort: votes


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Which parts are these? Large yellow and orange pieces with Technic pin holes
In an effort to identify sets in a second hand random LEGO collection we bought, we found some really obscure parts. Do you know which parts these are? Thanks!

The two parts on the right are Cockpit 6 x 6 x 5 with Hinge (30619). These have been used to make cockpits in LEGO Juniors and other very simple, low-part-count sets such as 4652:

The part on the left is Engine Block 4 x 6 x 2 with Wedge Cutouts and Technic Holes (45407). It is used to make up the front section of the tow truck shown above and has been used in similar ways in a few more sets in different colors.

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

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


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How would one add custom made 3rd party pieces to LEGO Digital Designer?
There are a number of producers of custom LEGO compatible pieces, how would one add such a custom piece to the LDD software, or otherwise make use of them?

Anybody at all? Not even a mention of what 3d format is being used?

Do you mean Lego Digital Designer?

I believe that is the current iteration. I am speaking specifically of the software available from the Lego company.

I thought I would clarify so I could update the question to hopefully get some more attention.

Thanks. For the record, I am willing to consider answers that address other software as well. But I currently only have the LDD, so am completely unfamiliar to any other software out there.

I believe it should be possible in most LEGO CAD applications, but LDD being a LEGO product it's unlikely they would officially support this type of feature. That's not to say it isn't possible.

Rin Rio-oki's answer is off the point i think hes asking for websites that are hosting more parts that can be manually added the Lego Digital Designer

@justanboy nijineko stated that they were willing to consider other software - and seeing as Studio offers both support for, and a tool to create custom parts, and is now officially supported by TLG in place of LDD, it's on point.

@justanboy thank you for your suggestion. I have attempted to improve my question.

In the comments you wrote:

...For the record, I am willing to consider answers that address
  other software as well. But I currently only have the LDD, so am
  completely unfamiliar to any other software out there. – nijineko

Brinklink offers two programs that could be right up your alley:

Studio 2.0 - A popular alternative to LEGO Digital
Designer, and

PartDesigner - A side-tweak program to make custom bricks,
where    you're able to export directly into the Studio 2.0 program.

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


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Identify 2011 set number, red car with criminal minifigure
This bag is from a 2011 set, it's 150-250 pieces and it appears to be a car.

This is from set 60007: High Speed Chase based on Chains M Plate M 5 Ø¸3, 2 Hole. There are only two sets with this part in Medium Stone Grey. The other set is the Star Wars UCS B-wing

Since this answer was written, the Technic Link Tread has appeared in Light Bluish Gray in five additional sets.


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What is this "patent pending" part?
I found this part in our LEGO collection, and I'm really curious what it might be, it looks old and says "Pat. pend" on the back. Do you know? Thanks!

It's a tie plate from the original 4.5V train system, specifically from a "switch point right":

http://www.bricklink.com/v2/catalog/catalogitem.page?P=x879cx1#T=C


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Is it possible to build a decimal to binary converter (binary counter) with LEGO?
I have seen many papers on logic gates built with LEGO, but I want to make a decimal to binary converter. There should be a counter as an input, with each press of the counter, the output 8 block shelve changes its configuration giving a binary conversion of the count.
Please help me as to how can this be achieved or at least how should I start the project given that I am new in logic and boolean algebra!

The easiest way is to use balls falling down a series of binary switches.  The disadvantage is that you will have to reload it with balls every so often.

Hi @PGmath, Any alternative, because this approach does not work with a standard apparatus. The LEGO model should be a static model that could be implemented at a molecular level, so any suggestions/alternatives?

At a molecular level??

Yes, of course, you can
As jncraton mentioned in a comment:

The answer to whether this is possible is definitely "yes". NAND gates can be built, and the required logic can be implemented using NAND gates. The questions is primarily about how this can be achieved.

Logic gates in LEGO
As you can see here folks have put extensive work into creating logic gates in LEGO.  The article referenced has AND and NOT gates.  You would need to put those together to get the aforementioned NAND gate.  If you're not familiar with logic gates it may be surprising that NAND gates can do it all.
Binary counters
As this articles shows you can build a binary counter out of flip-flops and NAND's.  And as wikipedia shows you can make a variety of flip-flops out of logic gates.
Now put it together
I'm sorry there aren't LEGO-level instructions for making all of this happen, but hopefully those are enough leads for you to figure it out.  Good luck.  I hope you put this together and turn it into a lovely youtube video or article to show us all how you did it.  You'd probably be a hit too on the LEGO convention circuit.  You can do it.

The answer is yes: This is a "mechanical counter" with the base being 2.
Google for "mechanical binary counter design".

Welcome to LEGO Answers! The answer to whether this is possible is definitely "yes". NAND gates can be built, and the required logic can be implemented using NAND gates. The questions is primarily about how this can be achieved. Can you expand your answer to help with that?

You could adapt the following mechanical binary counter from wooden pieces to Lego
https://www.youtube.com/watch?v=uotLQjvaG34


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Best set to build a tracked vehicle?
I want to build a tracked "all-terrain" vehicle myself (MOC), which should have the ability to climb over obstacles. Something alike https://www.youtube.com/watch?v=PXVO-wbWKxo
Now I'm looking for the technic model which has "the best" tracks to use. What would you recommend? It looks like I have the following options:

http://brickset.com/sets/8043-1/Motorized-Excavator
http://brickset.com/sets/42038-1/Arctic-Truck (is it even possible to combine multiple tracks into a bigger one?)
http://brickset.com/sets/42042-1/Crawler-Crane

What's the recommendation?

Another set with a lot of track parts to consider: http://brickset.com/sets/42055 (comes out on August 1st)

Thanks for the information, this one is a little bit too big for my taste. I think I'm not going to buy this year's flagship model and will instead go for the Porsche GT3 :-)

All 3 of the sets you listed actually use the same type of tracks, they are Technic, Link Tread Wide with Two Pin Holes #57518.
In my opinion this type would be your best option for driving a robot for a number of reasons:

Since they come as links the tracks can be made any length you want, allowing a lot of flexibility in designing the robot.  These are virtually the only link-based, variable-length tracks LEGO makes that would be suitable for driving a robot.
They are very sturdy and do not break or come undone easily at all.
They fit very securely on the cogs and practically never slip.  This is true even with a moderate degree of slack on the line, making it not necessary to measure the distances between/around the cogs to perfectly match the length of the track.

If you are going to be using these on your robot, you will need some cogs to drive them.  These tracks can be driven with the Technic Tread Sprocket Wheels #57520 (small - 6T) and 57519 (large - 10T).
I would also recommend getting some Technic, Link Tread Attachment, Double, Rubber #14149.  These handy little rubber grips fit on the tracks to give them better traction.  They work especially well on smooth, hard surfaces and for gripping stuff to climb over.

We just built the Crawler Crane and were very impressed with the treads.  Solid and no slipping as you said.  The net effect was that our crane acted more like a tank when going over surprisingly large obstacles.  Excellent design.


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Where can I go to get good custom LEGO minifigures?
I want certain LEGO minifigures, but TLG doesn't make them. I would like to find someone or someplace to get some good custom minifigures. I can pay.

Some of the answers in http://bricks.stackexchange.com/questions/4278/where-to-order-custom-mini-figs-in-europe may apply here.

There are several minifig-customizer businesses ... the most famous one is likely http://minifigs.me.


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Which LEGO vehicle set do I have here? 6 wheels and orange bricks
Can anyone help identify this kit? I received it in a bag with the number 5 on the outside and the year 2011. I'm really keen to build it but need some help identifying it so that I can get the instructions.
Thanks for your help.

Set 4635 - Fun with Vehicles. Specifically the tow truck pictured top center.


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Trying to work out where a 'spare' part goes on Wall-E (21303)
I've built a wall-e (set number 21303). This is the corrected version - and I've found, in addition to the 'obvious' spares, like 1x1 flats and round antennae, I have a 4x4 dark grey (4243831) left over. I can't work out where it goes

Image taken from google images, but its the same part
The only place where I can find one in the instructions in in step 65/page 54, and the parts count in instructions confirm there are two. The set's built and I don't notice any cosmetic or structural deficiencies in the design, but its bothering me
I've checked through the instruction manual a few times, focusing on the main body (since the arms, and head is paired parts, and there's no space on the neck for a 4x4)
What am I missing?

One is used in step 54 on page 49 and another one in step 65 on page 58. It's likely you missed the one from step 65 as it is just reinforcing the "flap" on the front of Wall-E - not a structural component.

I missed the one on step 54 on page 49 - I did think the use of grills over single studs was odd. Fixed.


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Connecting LEGO WeDo USB hub to portable Power Bank
Is it possible to connect the LEGO usb hub from education WeDo series to a portable power bank for power?
WeDo USB Hub

Portable Power Bank

Yes, it uses a standard USB charging configuration. These are designed to be universal, making power distribution easier and cheaper.

While this would power the hub, how would it be controlled then? I was under the impression the hub was controlled from a PC - via the USB connection.


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Why remote controls are seldom used in Technic sets?
(As of Jul 2016) According to this, it mention that currently there are a total of 376 Technic sets. However, this information mention that only 6 of them have the remote control function. This means that only less than 2% of all Technic sets have remote control.
Is there a particular reason(s) why remote control are seldom used in Technic sets?

Price is most certainly a factor

Many Technic sets are small and wouldn't fit motors or need remote controls.
Beyond that it is an extra expense which they need to leave out to make things available at various price points.  In some cases LEGO makes the motor optional to keep costs for the initial kit lower.  And the remote control adds complexity beyond that.
But the beauty of LEGO is that you're not stuck with their designs.  You can add these features yourself if you're motivated enough.


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Are there LEGO Hygrometer sensors?
Currently, there are light, ultrasonic, touch and sound Mindstorms sensors, but is there a hygrometer sensor from LEGO?

Is this for a specific version or any Mindstorm?

There is not one made by LEGO. However, there are a number of 3rd-party options:

Fatcatlab makes a Humidity Sensor (EV3 only).
Vernier makes a relative humidity sensor that can be used with the Vernier sensor adapter (EV3 and NXT).
There are also several temperature and humidity sensors from Grove that can be used with the mindsensors.com Grove sensor adapter (EV3 and NXT).


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Are there any LEGO sets that have these two parts?
Are there any LEGO sets that have the following parts:

Part 57518 (Link Tread Wide with Two Pin Holes)

Part 15035 / 18405 / 95292 (Large Shock Absorber with Very Hard Spring)

See related answer http://bricks.stackexchange.com/a/7895/7359 for an less expensive alternative to the shock absorber if size is not critical.

In the spirit of "teach a man how to fish and he will have food for a lifetime", here is how you can find your own answer to this question.

Determine rarity of the parts by going to BrickLink and search for the part name or number using the Catalog Search. BrickLink is a little finnicky with names and part numbers so it might take a few tries to get the right part (or to get it to return anything at all). For your items, 95292 only occurs in 3 sets, whereas 57518 appears in 29 sets.
You have several ways to go now - but the easiest is to have 2 tabs open, one for each of the list of sets. For each item in the shortest list, check if it occurs in the longer list (if the longer list is long, you can use Ctrl+F in your browser to do a text search on the page). Sorting each list by year might also help in doing this comparison.

For your selection of parts, it is quickly clear that there is no set that contains both. Not only that, the shock absorber you are looking for only occurred in 3 sets, all pretty limited in distribution (one of them being a truly Limited Edition of only 20k sets). Expect to be paying $10 per piece on BrickLink if you must have these. You might want to consider its shorter cousin 731c04 which occurs in 22 sets, including some lower-priced starter Technic sets. It can also be bought from many sellers on BrickLink for less than $2 per piece.


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LEGO Large Shock Absorber alternatives
Are there cheaper alternatives to Large Shock Absorber with Very Hard Spring (Part No. 15035 / 18405 / 95292 / 95292c01)?

As per the answer to your other question, please consider part 731c04 - Yellow Technic, Shock Absorber 6.5L, Complete Assembly - Hard Spring. Not only is it still in production compared to 95292c01, it also has a much wider range of availability and hence costs you less to procure as a piece on BrickLink ($2 vs $10).


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Metal Spring for LEGO MOC Simple Suspension
What is the most appropriate dimension (e.g. 20mm x 3.33mm, 5N/mm) of the metal spring for this LEGO MOC Simple Suspension so that it will not cause damage to the LEGO part surrounding it?

The inner space of the spring will be fine if you use an axle (4.8mm)
The outer space of the spring will be fine at 1L (7.8mm) and shouldn't rub against anything.
Here is a mockup of the spacing between everything, as you can see there is ample space between the spring and the orange pin joiners:

This shouldn't be a problem in your case but note that if the axle is rotating and the spring is compressed and is against a pinhole, the groove of that pinhole can cause the spring to uncoil and be damaged.


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How to disassemble this small Technic turntable, combination of parts 99009 and 99010?
How should I non-destructively disassemble the following parts, when they are newly assembled?
99009 Light Bluish Gray Technic Turntable Small Bottom

99010 Black Technic Turntable Small Top

These parts do not come apart. They are designed to be clicked into place and then remain connected. I have not found nor heard of a way that these can be separated without damaging the plastic and hence the functioning of the part.
The assembled component has part number 99009c01 - Technic Turntable Small, Complete Assembly with Black Outside Gear Section.

So, Part 99009 together with part 99010 will be one of those brick paradox (can be assemble once and cannot be disassemble)?

Not sure if it's a "paradox", but yes, once assembled the end result is a new part that cannot be returned to its original components. The new part's name is 99009c01. I've added this info to my answer.


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How to speed up the disassembly of large LEGO technic sets?
Is there any ways to help speed up the disassembly process for big LEGO Technic set such as the 42043 Mercedes-Benz Arocs?

Related: http://bricks.stackexchange.com/questions/7844/how-to-speed-up-assemble-big-lego-technic-sets-e-g-42043-mercedes-benz-arocs?rq=1

What are your goals with the disassembly? Do you want pieces so small that you can easily store them or do all pieces have to be disconnected? Do you want the result to be sorted in some manner?

Without knowing your goal it's impossible to answer. If the goal is "all pieces separated, but in one box" that's very different from "I need to fit it in a box for transport" or "I want to sort it into my existing collection". Browsing the "sorting" tag might help with the latter.

"Reverse Construction"
Most Technic models are built in a modular fashion. This particular model (42043 Mercedes-Benz Arocs) is no different, from the instructions you can tell it has been built in the following order: Engine/Chasis, Cab, Wheels, Truck Bed and finally the Crane.
Large sets often use red pins to join together major components. Therefore the best way to deconstruct a Technic set is to do exactly the opposite and work your way back through the instructions or at least the 'major components'.

Major components (for lack of a better term) are usually highlighted in the instructions and typically have their own numbered bags. Below you can see the truck bed.

The truck bed consists of a number of sub-components such as the truck outrigger.

Working backwards through the instructions you can either tackle the disassembly on a piece-by-piece basis or on each sub-component.
Use a Pin Pusher
Disassembling Technic models has always been a painful experience for me, particularly on my thumbs when removing the many, many pins and axles used.
I like to use a 'Pin Popper' to easily remove most pins. It's essentially a axle (Generally the longer the axle the better). I like to put a few Brick, 'Round 2 x 2 with Axle Hole' at one end to use as a handle and to stop the axle digging into the palm of my hand.

I have also started to use an alternative pin-pusher design to speed up the process.

Maybe you can use some techniques using the LEGO parts to avoid breaking it. You can use pieces to make your own "tools" to make disassembly process faster...
Here's an example of this.

Could you please add more info about this, link is not working

a search here for "technic tool" gives a bunch of examples.


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When did piece markings change from DUPLO to LEGO?
I've looked at some of the DUPLO bricks I grew up with, and compared them to newer ones. I've noticed that the knobs on the older bricks say DUPLO, while the newer ones say LEGO.
When did this change?

On the back of the yellow brick (not pictured) you can see writing "LEGO group"

According to Wikipedia:

In 1975, Duplo became its own product brand, with five sets made up
  exclusively of Duplo bricks.
...
In 1977, the Duplo name was dropped in favor of Lego Preschool.
...
The name Duplo was brought back in 1979, along with a new reworked
  logo.

Although I haven't found this information yet (most people likely see this detail as unimportant), it is possible that LEGO started with putting DUPLO on the bricks either when they first came out (in 1969) or in 1975 when DUPLO became its own "product brand". They likely changed it in either in 1977 (when LEGO called it LEGO Preschool) or in 1979 (when they brought back the name DUPLO).
According to Brickipedia:

In the Preschool range, new DUPLO bricks were introduced, including arches and the first DUPLO figures, which did not have movable limbs.

Considering the above quote, it is possible that with the new bricks the DUPLO on the "knobs" (as you call them, however the proper name is a "stud") was changed to "LEGO"; this was in 1977 on.
Source(s):

https://en.wikipedia.org/wiki/Lego_Duplo#History
http://lego.wikia.com/wiki/DUPLO#Start_of_the_theme_.281975-1980.29

Good awnsers. I estimate my "Duplo" blocks were bought around 1985, so it could have still been older stock floating around.  Thanks!


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How to convert a bar into an axle or pin - Using the Axel Hub with Four Bars
I would like to utilize the Axle Hub with 4 Bars (#48723) in a way that the four bars would become axles. What is the most concise way to accomplish that?
Here is a diagram of my end goal:

Here are couple of ideas. You could use pins:

Or axles with studs on the end:

Or axle connectors and axles:

Thanks a bunch, the picture references are great here! It looks like that third option would be the most stable so I may try that first.


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What is the best way to sort LEGO bricks?
I live in Hungary. I have tens of thousands of bricks at home. Over 1000 sets plus bricks. Most of the sets are sorted and packed separately, in their original boxes if they can with a box. Unfortunately some sets were mixed and kept in cardboard boxes. i. e.: 15 Harry Potter sets all mixed in a big box. The problem is that LEGO changed the colors in 2004. I must sort all parts according to color and type first. After that I can start putting the sets together from lists.
Is there a good way you know for physically sorting parts according to color, shape, etc?

This isn't directly an answer, but I encourage you to read the Evolution of LEGO Sorting: http://news.lugnet.com/storage/?n=707

Thanks a lot. I enjoyed it very much. One difference is that I stopped buying new sets. It is like quitting smoking. I managed it. At least for the last year or so.  I am planning to spend the rest of my summer sorting, boxing.

I don't think this is a duplicate but you should read this other question: http://bricks.stackexchange.com/q/6064


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LEGO bricks getting brittle, easily breaking. Insight needed
I was disassembling my LEGO set 7674. It is not new but certainly not old. It was built once. Was kept in a sealed box. No direct sunlight. In fact no light at all. Perfect storage conditions. Room temperature and humidity. While disassembling one of the parts broke in my hand twice!!! It fell apart.
First time this happens. I have thousands of sets. Have sets from the 70's and also new ones. Never saw this happen.
Any ideas?

Apropos: http://bricks.stackexchange.com/q/145/3971

I read this thread already. Very interesting. I have old sets from 70's and 80's did not have this problem. This set is from late 2000. Guess 2008. Clone wars. The plate was the first I tried to disassemble. After it broke I continued with utmost care disassembling the rest of the set. No problems during the rebuilding process. It could Ba a flawed part or just bad luck. I write to Lego. They immediately set me a replacement. No questions asked. It could be that it is a known case for them, otherwise they would have asked not questions. They wrote they may contact me with further questions.

There are a few things that will make ABS brittle, though you specifically say you didn't expose the bricks to those agents. It could be a bad batch, I suppose.

what color are the bricks, primarily?

Dark red. Lego mailed me replacement parts without questions. It must have been a bad batch.

Can you please add the reference of the brick that broke?

Dark red, plate, left, 3x6 w angle. This was from the SW series. The dark red bricks from mid 2000's are brittle as I have been experiencing recently. Another brick, 1x2 with rounded side just broke during construction. This was from the castle series.

Never had that problem besides the pirate ship.
The pieces with "claws", like the flag or the cover for the cannon holes, snapped.

What color are those parts? It can be due to the coloring.

For whatever reason, several Lego sets from 2008 are known to have had this issue. The trouble seems to be part specific. For example, the Lego Bionicle Karda Nui set 8686 Lewa Nuva that contained four Technic Beam 5 with Two Ball Sockets in FabuLime (Lego part number 4539223) often cracked upon initial assembly or disassembly. Replacement parts obtained directly from Lego exhibited the same issue.
Because of the consistent high quality of Lego manufacturing, on the rare occasion that we find a bad part, we tend to blame ourselves for the part failure. Logically, if the trouble is exhibited across the entire set (example: brittle parts) then it is probably safe to assume environmental issues like exposure to sunlight or temperature extremes. However, if the problem is only exhibited in a single piece handled with proper care, it is reasonable to assume manufacturing issues.
In my experience, Lego warranty part replacement services will never admit to or discuss known issues with Lego sets or parts. It must be against company policy. However, much to their credit, they will replace any part they have in inventory, no questions asked. So, if you have an issue like this again, contact them immediately. The catch is 'parts they have in inventory'. For older sets they might not have your part, so you would have to use a service like BrickLink.
I have thousands of Lego sets. Rarely, I have found a malformed or missing piece. The odd brittle piece problem seems to be confined to several 2008 sets. Maybe Lego was experimenting with new pigments, ABS formulations, or manufacturing processes that year?

Is it possible that the way you disassembled the set may have been hasty or under-careful? Some pieces are rather easy to snap. Perhaps include the ID of the pieces in your question to confirm this?

I am very careful with my Lego sets. I took photos of the part. Can I upload it here?

Yes, you can attach it to your question.

Please help. I am new to this site. I don't see any option for attaching a photo to the question. I tried "edit" without success.


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From what series is this brick? Duplo machine piece with yellow button, copyright 2007
We have ten of these, but I don't know from which series! When pressing the yellow button it makes a sound that could be a train or a tractor or something like that. We are curious. Does anyone know?

It doesn't look like any Lego piece I've ever seen. Does it have Lego written on it anywhere? Are there any numbers written on it? Any other angles?

I have updated the question with more info on the sounds it makes, and with an image of the back.

This is a Duplo Sound Effects Brick 2 x 4 with Water and Pump Sounds (Set 5605)  brick from 2008. It featured only in 1 set, 5605 Tanker Truck.


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How should I prepare one (currently built) LEGO set before selling it?
I have a large used LEGO set that I'm hoping to sell or gift onwards (Scorpion Pyramid). It's currently built (and therefore complete, and not mixed up with any other LEGO), but I'm not sure what to do to prepare it for passing on.

Do I take it apart? (I'm assuming yes)
Do I try to sort the bricks back into build-order bags (i.e. the mixture of pieces that comprised bag 1, bag 2 etc), or do I sort them some other way by type of piece and colour? What would a buyer expect to see?

When you obtained the set, were parts in several bags? Were they numbered? Some people may prefer to search parts in a big pile that having prepared bags when building their sets.

I bought it new, so the parts were in separate numbered bags, yes. I guess if I now provide numbered bags then someone who would prefer to have all the parts in a big pile can just open them all and tip them out!!

I have bought several used sets and it's a mix - sometimes people send the entire set built, sometimes split into larger chunks, and sometimes broken apart into individual pieces. It all depends on the current state of the set (fully assembled, partly assembled) and on the dimensions and availability of the shipping supplies. In the US it is easier to break the set apart and fit it in one of the pre-priced USPS shipping boxes that give you a uniform rate.
As a buyer, I always break the sets I receive down to the individual items and then inventory the sets using the full set inventory. Time intensive but it assures me I get the full set, and that there are no short-cuts/substitutions etc.

I haven't bought much used Lego. But normally an entire set would be mixed together into one or two ziplock bags.
Given that the set is currently assembled, are you sure it has all the parts? Sometimes there are loose parts or figures that don't make it onto the final build. You may want to double-check with the instructions by rebuilding it.
Finally, is the set dusty or dirty or oily? If so you may want to consider dusting it or washing it (mild, warm, soapy water).
If you're feeling adventurous you could re-sort the set into bags corresponding to the instruction steps. I'm not sure a buyer would expect that. Or, perhaps more easily, if you sorted the parts by colour, it might make it easier to verify the inventory.

Thank you! Yes, I'm sure it has all the parts, as I was the one who built it and it's all been hanging out on a shelf ever since! But I'd certainly be willing to break it down for a buyer. I wonder whether a buyer would prefer parts sorted by colour or by size, but I guess there's some discussion of sorting in other questions on the site!

As a general answer, it depends. Having to search for parts in a pile of LEGO can be one part of the pleasure of building. Unless the model has 1000+ pieces and it can become a nightmare.

If you have time
You can disassemble the set by following the instructions in reverse order and pack parts in several bags, then give them numbers in reverse order.
Otherwise
One quicker solution may be to:

split the pyramid from the top to the bottom
disassemble each part and put the parts in a bag
number the bags in descending order (e.g.. 7 for top, 1 for bottom)

Since LEGOs are very often assembled from bottom to top, the other person will just have to open the bag 1 to start the assembly, etc.
But the instructions may not match perfectly with the order of the bags, so you should probably inform the other person that if a part can't be found at a given step, it should be in following bags.


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What's the name of the set including this piece? Red Technic and system pincer?

This piece is a pair of claws/tweezers the I don't know the name of, it's part of the set and might help.

Looks like that's Exo-Force set 7701-1, Grand Titan.


text:
How to buy a lot of LEGO Technic bricks?
At first, I bought 6 lbs of LEGO Technic bricks.
however it was dirty and used. Also there were only holed bricks and I can't find many gears or axles.
I want to make Technic creations or MOC's, but I don't know how to get enough bricks to make it.

Usually the most economical way to acquire LEGO elements is to just buy full sets (ideally on sale). So if you have a particular design in mind, look at the currently available - or recently retired - LEGO Technic sets and see which one would have all or most of the pieces you would like to work with.
You can also check eBay and BrickLink for used LEGO Technic sets. They are less expensive than new condition sets, but are still well taken care of by the original owner. If a few pieces are missing they are even cheaper. Building up a LEGO Technic collection this way usually works out better than just buying random lots from resellers.
In general BrickLink is the better way to go as the sellers are also dedicated LEGO fans and won't sell you something they wouldn't be happy with themselves. However eBay could be cheaper. If there are good pictures of the used set, and they are from the original owner, you can find great deals.
In summary, when you buy pre-owned, it is best to find slightly used full sets from original adult owners. The pieces will be in better condition and the selection of parts will also be better, rather than just buying random lots where you don't know the history and condition of the pieces, and the seller is not the original owner.

My preference is BrickOwl over BrickLink. I find it easier to use.

I would buy the EV3 Robot kit first, and fill in the things you find you need later on Brick Link. Besides that a full pocket of money is very helpful.


text:
LEGO Submarine waterproofing functional parts (e.g. motors, RC receivers)
From my understanding, the motors and RC receivers are not waterproof. Thus, the LEGO submarine from Sariel's LEGO® Workshop rust after sometime.
So, is there any way to make the motors and RC receivers water-proof, so that it can be used as a submarine?

The method they used to secure the battery/controller was to wrap it in a sealed plastic bag, something similar to this could be done for the motors.  It would be more difficult since you would need a water tight bearing for the rotating shaft to exit the sealed bag.  These bearings are complicated and will still always allows some small amount of leakage.
An option to help prevent water leakage would be to fill the motor with a non-conducting fluid to displace any inflowing water, something like mineral oil.  I'm not going to try this with any of my motors, but it should work.  There is history of using mineral oil for electronics to aid in heat transfer (used by some extreme CPU over clockers) it is non corrosive and non conductive and will not rust the metallic components.
As an alternate just letting water in seemed to work for a while, you could prolong motor life, by ensuring the internals were thoroughly dried after removing them from the water.  This would most likely involve opening the housing and a dry air flush.  This would slow the rusting, which is much faster when water is combined with exposure to the oxygen present in air.
EDIT
Another method that could be used with actual Lego parts, use the Lego magnets to couple two shafts rotation together on either side of the plastic bag around the motor, this should have zero leakage.  There would be an upper limit on the torque possible before the magnets would slip and it would potentially cause wear onto the plastic bag if there is contact with the moving parts.

In this video:
Building a Lego-powered Submarine 3.0 - balloon and compressor

They use a tupperware box, with magnets either side, motors on the inside of the box, and some low-friction tape to reduce slippage.  Seems to work well.

Container is from IKEA 365+ range. Seem to be 492.777.75. Just in case someone needs this in the future.

The only option is to seal the electronic parts away in a waterproof container, like the plastic bag used in Sariel's video contained in the question, or in a clear plastic water pitcher, like in this video. The tricky part is then providing waterproof seals for the propulsion shafts that need to penetrate the hull. The different approaches tried can be seen beginning at the 1:53 mark and finishes at 3:20 with the application of a small, non-LEGO O-ring, sticky foam tape and a metal washer on the other side:


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How do LEGO Technic pneumatics parts age?
I recently bought LEGO Technic 8868 (Air Tech Claw Rig) and 8460 (Pneumatic Crane Truck) models. I noticed that the pneumatics tubes seem to have been changed since the colors are different from the instructions manual.
Since these models are respectively 24 and 21 years old, a possible explanation is that the original tubes have been lost.
But it may also be due to aged tubes that needed to be changed. How do tubes change when they're ageing? Do they become less flexible and break when they're failing? What is the lifespan of these tubes?
It looks like the pneumatic cylinder, pumps and valves have not been changed and they still work. So I think that they can last longer than tubes.

The tubes generally age very well and I have never experienced a problem with them (I have had several of these sets over the years).
I would double check that the pump is working correctly and you have definitely not got a poor connection somewhere (a leak).
Double check also for blockages in the hard plastic dark old grey connecting tubes that are clipped on and the 'T's. These have a smaller inner diameter than the rubber tube and would be the first to get a blockage if something has got in to the system.
If you are certain its a tube problem you can buy replacement tube online. I would carefully double check for another problem before buying tube as the tube rarely fails unless it has been exposed to chemicals or a lot of sunlight.

I don't need new tubes or have any problem with them, they work. I was only asking how tubes age. Please remove your link, your answer looks like a spam.

You did state it may be because your tubes need replacing and I also answered your question based on 30 years of experience - i.e. the tubes age very well and I have never come across tubes that have failed due to age. I feel your response is a little unfair - if you think the answer is wrong and unhelpful, that's fine, no need to berate someone who is looking to help you.

You answered "I would double check that the pump…" but everything in my pneumatic system work well, so that's a bit off-topic. I'm sorry that you took my comment badly, but your answer is at the border between interesting and spam, see this related answer on Meta: "If a large percentage of your posts include a mention of your product or website, you're probably here for the wrong reasons." That's the case for the end of your answer.

@A.L Be careful to check your facts before correcting or criticizing someone. A link to a place selling LEGO in a site dedicated to LEGO is in this case perfectly fine. In fact, in certain cases such a link factors in to why an answer is marked as accepted! We almost always use and recommend sites like BrickLink, and because we aren't affiliated with the LEGO company, that's okay.

@CalebWoodman I'm sorry if my comments looked agressive. The first sentence is a perfectly valid answer, but I was surprised by the following of the answer that was interesting but 1. Didn't answer to my question 2. Looked like an introduction to the linked shop. I'll try to be more diplomatic in the future.

@Carl Goss can you please give a number about over the years? Is it several years or decades? Thanks.


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Does the LEGO "Power Functions Extension Wire" (8886) work in both directions between old 9V and new Power Functions devices?
Here is the LEGO "LEGO® Power Functions Extension Wire" (8886):

We can see that the left connector can connect to old 9V electric bricks or wires and the right connector can be plugged to the new Power Functions connectors.
The LEGO website gives this description:

Power up your LEGO® Power Functions creations with this 8" extension
  wire. Make your models bigger, better, and more mechanized than ever
  before!

Allows you to connect your LEGO 9V electric systems to the new Power Functions!
Extension Wire is 8" (20cm) long

(emphasis mine)
Does this cable work in both directions?

Can it power a new Power Functions motor from an old battery box?
Can it power an old motor from a new Power Functions battery box?

Do switches like the old one or new one let you control new and old motors respectively?

I performed my own tests with:

battery boxes: old 9V and new Power Functions
motors: old 9V and new XL
the 8886 cable
one electric plate (4757) (required since the connectors of the 9V motor are on the bottom while the 8886 cable connects from top)
2 grey Propeller 2 Blade 9 Diameter (2952) in order to show the rotation of motors

Here are the results: it works in both ways with motors and battery boxes.
Old 9V motor powered by new Power Functions battery box, with the 8886 cable plugged to the motor through the electric plate:

(the cable is out of the photo frame but I guarantee that there's no trick)
New XL motor powered by old 9V battery box:

As you can see, the connectors of the 8886 cable have different colors, the 9V-side is a lighter grey.

According to Customer reviews on the official website, this cable enable powering motors in both ways between old and new power functions versions:

This cable allows you to power the new 9v motors from the old 9v system or vise versa..

Author: heavyD.

But there is an incompatibility between the old battery boxes and the IR receivers:

This cable also powers new motors from the old battery box, but it cannot power an IR receiver, which requires the new battery box and all 4 wires of the new cable. (This cable only converts the 2 motor-powering wires.)

Author: Technic010.

Power functions has four wires, "Electric system 9V" only had two. Two wires carry the motor control lines. The other two wires carry a power supply which is fixed polarity, never speed controlled and is not switched by the IR receiver (though it is switched by the switch on the battery box). The adapter cable connects the two wires of the Electric system 9V to the two motor control lines of the power functions.
Things that will definitely work:

Powering any "Electric system 9V" kit from a power functions power source/controller. Some of the Early kit will require use of an Electric plate or an old style cable because it has it's contacts on the bottom.
Powering an ordinary power functions motor or a set of power functions lights from an "Electric system 9V" power source/controller.

Things that definitely won't work.

Powering a power functions IR receiver from an "Electric system 9V" power source.
Powering the power functions servo motor from an "Electric system 9V" source.

Things I can't find enough information on.

How the power functions switch behaves. In particular whether it draws it's input power from the fixed-polarity lines (which would make it incompatible with "Electric system 9V" power sources) or from the motor lines (which would make it compatible with "Electric system 9V" power sources).

Actually there IS a way to power IR Receiver/Servo motor from an old 9V power source - daisy-chain them to a new (empty) battery box, switched to the correct position (can't remember which one) - that way the switch in the battery box powers the power supply lines as well. Maico Arts uses that trick to power his servo-motor GBC modules, for example

mmm, just be careful about polarity....

Yes, definitely - I didn't emphasize this enough with "switched to the correct position"

The thing is the "correct position" depends on how the adapter cable is connected to the electric system 9V source, and what output polarity the electric system 9V source is set to.


text:
What LEGO Power Functions parts do I need to make an RC car?
I'd like to make a remote control car with steering and forward/back functionality.
Looking at the LEGO Power Functions parts I'm assuming I need the following:

A battery box (8881 or 8878)
A motor for drive (8883, 888003, 7772)
A servo for the steering (88004)
A IR receiver (8884)
A IR remote (8885)
Some Extension Cables? (8871, 8886)

But I'm not sure how the IR remote is configured to control the motor/servo or whether I need an IR receiver (8884) per motor/servo, or whether I'm missing another part.
What Power Functions parts do I need to make a LEGO remote control car?

The servo is not mandatory, you can use a standard motor with elastics for the steering: https://www.youtube.com/watch?v=jQ5ug1CwRa8 (warning: aggressive music)

Your assumptions appear to be mostly correct. Just for clarity, these are the minimum parts required:

A battery box
A motor for driving
A motor for steering (unless you want to try a steer-on-reverse single motor design)
An IR receiver (these can support two motors each)
An IR remote

Extension cables and/or lights are optional depending on the design of your vehicle.


text:
I need help finding what set these pieces are from, AM 02066 and AM 02067
I recently found a bag of pieces from an older set that I lost the instructions to, and I don't remember the set name.  The set was a blue plane, and the cockpit pieces say AM 02066 and AM 02067.  I put this set away in 2007 when someone threw it so it is old and I can't find it anywhere.

Those numbers sound like manufacturing timestamps and not part numbers.  Can you post pictures of what pieces you have?  But LEGO hasn't made many blue planes so is http://www.bricklink.com/v2/catalog/catalogitem.page?S=712-1#T=S&O={} the one?

No it isn't and it definitely was supposed to be a plane from ten years ago.  I don't know how to post a picture on this question though.

Can you give us anything else to work on? I can't find any blue planes made in the years 2003-2007 that look like matches.

Most lego sets that have numbers printed on them, the number matches the set number. Nothing turns up for those two numbers.

Do you see your set here, here or here ?

The set you are referring to is Mega Bloks set# 9728, Blue Thunder.  Instructions can be found here: https://support.megabrands.com/media/playbooks/9728.pdf

The set "gold hunt" from Lego Agents contains a sizeable blue plane. Any chance that's it? It's from 2008, not 2007, but it's another blue plane that comes to mind.


text:
How can I make an EV3 vehicle follow an elliptic equation?
Has anyone succeeded in having the EV3 driving base moving following an ellipse? I would like the kids to think about how would we program a satellite orbiting around earth.
They would input the equation for the ellipse and then they will have the robot driving around it. Any thoughts?

I think it would be more realistic to have the robot drive in a straight line but have a linkage to the foci of the ellipse that "pulls" the robot towards the center of the ellipse just as orbiting objects are pulled toward Earth by gravity.
For example, you could use two nails in a board as the foci. Tie a string in a loop to use as the linkage. Place the string loop around the nails and attach to the side of the robot. Drive the robot forwards (no steering). It will travel in an ellipse. You could even attach a pen to the robot to draw the ellipse.

I'm not too sure from looking at your drawing but does this method draw an ellipse or something more like a race course?

This is a well-know method of drawing an ellipse. https://en.wikipedia.org/wiki/Ellipse#Drawing_ellipses

Sorry. I can see what you mean now.


text:
How to run "Power Functions" devices from an electric wall plug?
In this video showing an example of Great Ball Contraption (GBC), we can see (at 1:35) that some trains powers are used to run Power Functions motors:

That must be more convenient than having to change batteries after several hours.

What parts are involved, from the electric wall plug to the final motor?
I guess that the following parts are used:

Power Adaptor (70931) plugged on wall plug, that provide current through a wire connected to…
Train Speed Regulator 9V (2868b) that outputs current through 9V plugs
a Power Functions Extension Wire connected on 9V plug that provide a Power Functions-specific plug (8886)
any Power Functions motor, e.g L motor:

Are my guesses correct?
If I remember correctly, I have already seen in some videos that the Technic Control Center II (2840c02) was used in place of Train Speed Regulator. Does it work too?
The Train Speed Regulator 9V are Technic Control Center II are incredibly cheap, are they the cheaper way to power devices from an electric wall plug? The Power Adaptor is relatively expensive, but it's probably possible to find a cheaper and compatible adaptor.

Hopefully somebody will be brave enough to try it.

@chicks We have a better view of the wires in this video, I'm 99% sure that I identified the parts in my question. A confirmation would be nice though.

WOW. This is some serious quality post.

It is pretty much the most used setup in Europe for GBC. Side note: if you need to power specific PF electronics such as the step motor or an IR receiver, the conversion cable won't be enough as it  only provides power to PF C1/C2, not 0V/9V. You can however add an empty battery box to power these too provided it's setup correctly - see https://www.youtube.com/watch?v=0j8QXHI6EaY for example for explanations

What you describe is indeed the most common way to GBC modules, but it's worth noting that one adaptor+regulator can typically power more modules (it depends on the modules), sometimes only one end of the extension cable is used, when placed on the regulator, it effectively provides a power functions "plug", and if you want to power more modules, the wiring can get a little easier to handle, when every module is essentially connected to a regulator.
Another option is an NXT with the official rechargable battery mounted and an adaptor plugged in, and then of course NXT cables to an NXT motor (I don't remember if NXT->PF cables exists, but NXT->9V cables does and you have mentioned that the PF extension cables can attach to 9V). I have also seen modules with an RCX, I think that has a plug for an adaptor directly, but I'm not sure, I don't think I've seen GBC modules powered by EV3's yet, but there's probably a solution. - Probably more expensive, but having an NXT in a module allows other possibilities, especially if you also put in some sensors.
As Mr. Shiny and New 安宇 mentions the rechargable battery box is a third solution.
All of these solutions have the advantage that they only use official unmodified LEGO parts.

I just happened to finish a homemade solution to this problem a few days ago — so while I can say this works, it isn't exactly long-tested. I made an adapter to connect a 9V power source to the battery contacts in a regular Power Functions battery box.

The trickiest part is making the connection to the positive terminal of the battery box (which is a recessed flat contact as opposed to a spring). There are lots of ways the details of this could be handled, depending on the materials and tools available. I used two AAA-to-AA battery size adapters that I had on hand — for this purpose, they're just battery-shaped plastic objects with contacts on the ends. One of them has only the negative end connected, and the other has only the positive end.
(Perhaps there are LEGO parts that could be used instead? 2×2 cylinder bricks are a bit too large…)
Hook up these two “dummy batteries” to your power adapter. (If your power adapter has a barrel plug and you don't want to chop it off, that may be the because you need a matching jack. I just bought a surplus adapter and cut the plug off.)
The two “batteries” go into the “endmost” slots in the battery box — these are the two that are closest to (negative end) and farthest from (positive end) the switch, paying attention to the zigzag shape of the two sides of the box. These are the two slots that are actually wired to the switch and output; the rest are just to make connections between six separate cells, which we don't need.

Materials used in this particular build:

Two AAA-to-AA adapters, with holes made in the sides for the wire.
Wooden dowel, to fill out the interior space, with a groove cut in the side to make room for the wire.
Spring, at non-contact end.
Ordinary brass thumbtack, pressed into the contact end of the dowel.
Wire, soldered to the inside of the tack.

There are surely much less complicated ways to do this, such as not bothering with the plastic adapter, though then you need to be more precise about making things the right size.
Pros of this method:

Cheap if you have the right materials on hand.
You get the reverse/off switch and overload protection circuit that's in the battery box (unlike, say, cutting a Power Functions wire to make direct connections, which would also work).
No bulky speed control box if you don't need it.
The same adapter can power an old-style 9V battery box, a Mindstorms brick, or anything else taking 6 AAs.

Cons of this method:

Not an official LEGO power adapter.
Might be stressing the battery box due to long-term higher voltage than AA batteries under load.
You get no speed control (if that's something you care about).
Ugly; you have a battery box with the covers taken off.

I've heard that the rechargeable battery box sold by LEGO can power a motor while it is plugged in and charging. If your motor is in a stationary position, this could be sufficient.
I've also read, in customer reviews on the LEGO website, that it is possible to daisy-chain power-function devices to the old 9V motors, however, I'm not quite sure what is required for that.

Thanks for your answer. The rechargeable battery box is really expensive, the 2868b regulator and 2840c02 are 30 and 5 times cheaper, so I found them more interesting. About daisy-chaining, I asked a question about this: http://bricks.stackexchange.com/questions/7939/does-the-lego-power-functions-extension-wire-8886-work-in-both-directions-be If it works for old 9V battery boxes, it should work with the big regulators too.


text:
What set(s) are these 2x2 hexagon bricks from?
I've inherited quite a few interesting pieces from relatives who outgrew LEGO. Any idea what set(s) these came in? They don't have any numbers so I can't look them up on pick-a-brick or anything.

Do these bricks have any "LEGO" markings on them? The most obvious place would be on the studs of the blue octogonal piece (2nd from the left). So far I haven't found anything yet that matches so I'm wondering if this is perhaps a clone brand ....

yes, they all have lego markings on them.

Now I need to get some and use them as pipes for a Mario bros. set.

You have the following pieces:

6037 - Brick, Modified Octagonal 2 x 2 x 3 1/3

6043 - Brick, Modified Octagonal 2 x 2 x 3 1/3 Corner

6042 - Brick, Modified Octagonal 2 x 2 x 3 1/3 with Side Studs

6032 - Brick, Modified Octagonal 2 x 3 x 1 2/3 Sloped

These were used in about 10-15 sets during a brief period from 1995-1998, most of them in the Aquazone theme, but some made their way into other themes as well (e.g. Castle).

Those are modified octagonal bricks numbers 6037, 6042, 6043, and 6032.
http://www.bricklink.com/catalogList.asp?pg=3&catString=7&catType=P
The blue corner pieces (6043) are only from set 6190-1 Shark's Crystal Cave

The others are likely from the 2162-1 Hydro Reef Wrecker


text:
Cheapest and Simplest way to build a LEGO Technic car?
Having no LEGO Technic parts at all, I'm looking for the cheapest and simplest way to build a LEGO Technic car which can be combined with two Lego Technic motors to drive forward and backward (phase 1) and to steer to left and right (phase 2).
I see two possibilities:

Buy a complete LEGO Technic product (which one can you recommend?)
Get all the parts needed online (which parts do I need?)

I would like to combine the two motors with my Raspberry Pi.

I think your best bet is to start with 42048 Technic Race Kart and a 8293 Power Functions bundle. This gives you just one motor, but that's enough for propulsion (going back and forth).

You would need to look into a motor driver board (for example the DRV8835) for the motor, and look at schematics for a power functions cable mod to be able to drive the motor directly from the RPi - see this question for several suggestions on how to do this..

For steering you can look into a 88004 Servo Motor, or use a normal Medium motor with extremely fine control or a good set of gears to be able to make small steering adjustments.

Amazing as usual, Phil!

Note that you will end up with a big set of power functions parts on a small chassis - the go cart is big enough to carry them, but not by a large margin. The two photos are not at the same scale.

Thank you. Very helpful. Having read some tutorials I'm now thinking about getting the "BrickPi", which will help connecting Lego motors and sensors to my RaspberryPi. In this case I wouldn't need the motor driver board. This is not the cheapest solution but it looks very simple to me.

Yes, the BrickPi is a great solution as well. And to @Móż point: yes, it becomes quite cramped but if you remove the seat and the fake engine, there is enough space to place the motor and the battery box. I have done this in my classroom program.

Oh, you might want to add the BrickPi details as an answer to this post as well - could be helpful. @mosquito87


text:
Bag 2, 2011 set, ID 135149
Can anyone identify this bag? It has in it what looks like the grill of a truck, or skis!

Blue jacket, fearful face, gray round piece.
Mainly black blue and white. 2011 printed on bag.

I KNOW IT'S 2011 BAG 2. THAT'S ALL I KNOW. SORRY FOR THE CAPITAL LETTERS!

Welcome to our site! It's good to get a new member. I'm going to edit out the all-caps, though, if that's okay.

So Parton, there is a little checkmark icon under the up vote/down vote counter on each answer, if you press it, it will turn green and you get a few points. Pressing it means that the answer you used it on is the one you accept. Just accept whatever seems to be the best or most accurate answer. The one that this post has looks like the right one!

Set #75915-1: Jurassic World Pteranodon Capture

THATS IT!!! Thx!


text:
How steep a grade can a LEGO train go up?
I realize this would change based on how much weight it's pulling. How about using an engine pulling 3 cars? I'm guessing that sets available for sale now would have similar power. I have the engines from sets 60052 and 60098.
Thanks for any input you can provide.

Carriages can be very different, and as such a poor unit of mesure for weight. Typically we say that any train should be able to handle a climb of one plate for each piece of track (16 studs).

I've successfully run a single motor pulling two cars from 7938 and the locomotive all the cars from 79111 up a spiraling incline of two plates per track segment. I terminated the experiment after I ran out of track and table space. If the track was straight I probably could have pulled more weight.

Anecdotal input:
I run my 7745, 7740, 7735 (with extra carriages), 4458 (with 2 clubcars), 4563 and 4564 up a 14 brick total height using 16 sections of straight track.
On the main sections this is one brick per 16 long track section but at the top and the bottom I smooth out the incline with 2 plates and then 1 plate. (Otherwise the carriages, especially the club cars, bottom out on the track).
These are 12v and 9v models and not the Power Functions models you list so your motor and track characteristics are likely to be different.
Space limitations are the reason I use such a steep incline and I do have to make sure I keep the electrical contacts clean to ensure constant power delivery or I can get some slipping and wheelspins.
Also this is likely putting a fairly heavy load on the motors, luckily I have spares and I don't run my trains for long periods of time but I don't run my 7727 on this section of track for fear of damaging it's precious red motor!
I think this is the absolute steepest you could get away with and if you have the space, two plates or one plate per track section as suggested here and in other places on the web should be your goal.

Thanks for your input! I've been doing LEGO for a long time, but this my first foray into trains and I'm hooked.


text:
Chaining Connections
The LEGO 2x4 brick is somewhat of an icon of LEGO, and the majority of official LEGO bricks can connect back to it. However, the number of bridging bricks required can vary, depending on the piece. Some pieces, like a 1x1 Round Tile, can be connected directly to it; however, others, like the Technic Axle 32, require additional pieces (in this case, the Technic Brick 1 x 2 with Axle Hole) to bridge the gap.
The piece I can think of that requires the most of said bridging pieces to connect back to a 2x4 is the body of the Bohrok Canister assembly, which requires 4 pieces to reach the 2x4: the lid, the hanger clip, a Bohrok ribcage, and a 1x2 Brick With Pin. My challenge is, can you do me one better? What piece takes the most bridging pieces to connect back to a standard 2x4, and what is the chain required for it?
Rules:

The piece must be official LEGO; no messing around with off-brand pieces with absurd new connection types.
All connections used must be legal; no strapping things together with rubber bands and calling it good (that would take all the fun out of it).
There must actually be a method of connecting the pieces together; pieces like the ball used in Scorpion Palace or any of the BIONICLE canisters without built-in studs are just cheating.

This might actually be a good puzzle for Puzzling.SE, but you already posted it here, so.

I feel like puzzling is more about wordplay or math tricks than physical stuff.

This is a nice break from the usual "what is this obscure part" -- no problem with this IMHO.

I suggest that you post your best solution as a separate answer (possibly with pictures), so it can be separately commented and voted upon.

@Wrzlprmft Sadly, I no longer have any of the original Bohrok canisters. However, physical construction of the winning chain isn't necessarily a requirement; this is more a parts knowledge test than a supply one.

This answer is based upon the wrong assumption that Technic chain links and conveyor-belt links (a.k.a. bulldozer chain links) connect to nothing except each other.
As remarked by Ivan Sanchez, this is contradicted by this set, which uses a connection between a conveyor-belt link and a standard arm/rod.
Assuming that these chain links only connect to each other, the only way to connect them to something else, is wrapping eight of them around a standard 16-cog gear. (You can also wrap six of them around an 8-cog gear, but I would not consider that a robust and intended connection.)
Finally, the gear can be connected to a length-3 axle with stud, which in turn can be connected to the bottom of the 2×4 brick.
For bulldozer chain links, this looks like this:

Now, it depends on how you interpret the challenge: You need nine other pieces to connect the chain link to the 2×4 brick. However, many of those pieces are again chain links and there are only two pieces between every chain link and the 2×4 brick.

I'm terribly tempted to give it to you... I'm just trying to figure out whether connecting those links to standard rods is legal. If it is, a 1x4 antenna drops the chain down to one link.

I think you can also actually clip them to one of the various thin antenna pieces like 2569, although I would assume that's not a "legal" connection.

Couldn't you use a 88072 Plate, Modified 1 x 2 with Arm Up to connect the thread to the brick? I think 40175-1 Policeman with Cookie and Stinger polybag is using that technique.

@IvanSanchez: That’s what Lepidolite Mica suggested in the first comment, leaving the question whether it was a legal connection, which the set you reference answers. See my edit. (At least that set is younger than my answer.)

Thornax, 7 connections.
This is just a start, but here's a 2x4 connection to a BIONICLE thornax.

BIONICLE Ball, 6 connections
The extra two pieces are needed to hold the ball in place, making it truly connected.

Ooh. Sorry, but this brick and a 4 axle can bring the Thornax down to a 4-piece chain, and it can be used with the Zamor sphere as well. You're on the right track, though!

You could also get it down to 3 pieces by putting a stud in the Thornax launcher's pin hole (maybe not technically legal anymore, but I know LEGO has done it before).

I have another case for 4 connections.
18592 - Propeller 3 Blade 13 Diameter (Ninjago Airjitzu Flyer Vortex Rotor), can be attached to 2 x 4 brick with a help of following 3 parts below:

18590 - Technic, Gear 8 Tooth with Pin Holes and Ninjago
Flywheel Socket - Short Shaft
18585 - Brick, Modified 2 x 4 with Pin Holes and
Flywheel Socket (Ninjago Airjitzu Flyer Handle)
16965 - Human
Tool, Rip Cord Flexible with Handle Thick for Ninjago Airjitzu Flyers

I could do it with 2 pieces, 6558 Pin 3L and 2444 Plate, Modified 2 x 2 with Pin Hole. Or maybe even 1 15461 piece if putting a stud in the pin hole is allowed.

None of these parts provide a connection and I would consider them cheating similar to using gravity to call it "zero piece solution", rubber bands or string with studs on both ends to call it "single piece solution".

Sorry, I forgot to list the black circular piece that connects to the propeller. Those pieces would connect to that piece and hold the propeller in place. I've done something similar to attach it to an axel before.

In any case, my suggestions probably aren't 'legal' so this isn't a bad answer.

If I understand correctly, your solution is targeted to be applied on top of 18590 piece, where Trans-Clear cone is used to be attached in a set. I cannot see how such solution could be applied from the bottom of the propeller. Or am i missing something? In such case propeller would only hold if notches within propeller wouldn't align with cuts on 18590 part. Otherwise the propeller would fall off. So a bit of grey area here, as luck is now involved here.

Sort-of, although after some testing, it's still possible to spin the propeller and detach it... I found little bit different way to do it in 3 pieces though. And a really goofy piece which can do it in 2 (this piece which has been attached to a Technic pin hole in Polar Base).

Are you counting sub-assemblies as separate pieces?
How about part 983 a Minifigure hand.
That requires 981 Arm, 973 Torso, 970 Hips, and 971 a Leg.
For a minimum total of four interconnections.

...you really don't need any connecting pieces to attach a minifig hand to a brick...

Minifigure hand can have any piece with 3.18 mm bar attached. You can then use any part which has both 3.18 mm bar and stud (or anti stud) to get hand attached to 2 x 4 brick. For example, Bar 1L with 1 x 1 Round Plate with Hollow Stud (32828) can be attached in two ways (with stud and anti-stud). This would bring it to just two connections.

Actually, ignore my suggestion above. Minifigure hand has a stud itself! This means it can be attached directly to 2 x 4 brick's anti-stud on the bottom.

Maybe one of the LEGO storage systems (https://www.lego.com/en-us/product/lego-8-stud-black-storage-brick-drawer-5005718) or apparel could be a candidate?


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How to create a LEGO Technic tank steering system
I found this video containing a steering system for tracked vehicles. Are there any steering system(s) that are more simple than the one shown in the video, and include a guide (in LDD or pictures format) to replicate for a tracked vehicle, such as a tank?

The simplest method would be to just have two motors, with one motor driving each side of track.
To go forward, both motors forward; backward both back; to turn set one motor to go faster than the other, only drive one side, or set one forward and the other backward.  It is a fairly common treaded vehicle steering system.
The linked system with dual differentials, a drive motor, and a control motor, seems quite excessive to me.
However, it come with some cost as the system move without feedback, it's unlikely that both motors will be driven at the exact same speed. Variations in the build (e.g. how tight bushings are) and the motors (torque curves) means that it'll generally drive in a (large) circle unless you actively correct for it. To make it move relatively straight, it involves a lot of fiddling with loosening / tightening parts, and even then one may often find that it no longer drives straight on a different surface.
With a dual-differential drive, there's generally enough friction that it will indeed drive "exactly" straight when the drive motor is on - and if it doesn't, one can just add a bit of friction (e.g. clamped bushings around a stud) to the control motor to make it drive straight.

Note that it can be a pain to ensure that the tank actually drives straight with the 2-motor system.

@TLW, is it possible to let me know what type of pain you are referring to?

@user275517 - "pain" in the sense that, without feedback, it's unlikely that both motors will be driven at the exact same speed. Variations in the build (e.g. how tight bushings are) and the motors (torque curves) means that it'll generally drive in a (large) circle unless you actively correct for it. You can make it relatively straight, but it involves a lot of fiddling with loosening / tightening parts, and even then you'll often find that it no longer drives straight on a different surface. Hence, "pain".

@user275517 - With a dual-differential drive, there's generally enough friction that it will indeed drive "exactly" straight when the drive motor is on - and if it doesn't you can just add a bit of friction (e.g. clamped bushings around a stud) to the control motor to make it drive straight.

@user275517 - At one point I was part of an (informal) competition to see who could build a robot to drive in a (relatively large) pentagon and return to the start most precisely. 'Twas fun, but I ran into this problem at first.


text:
Where can I create a custom figure?
So while it is nerdy, I want to create the Call of Duty: Zombies characters out of LEGO in real life to play with or model. But I can't find any sites where I can create them. Can someone help?

Welcome to our site! I hate to tell you this, but this is probably a duplicate of another question, and might be closed. So, in the future, just make sure to check and see if the topic is already covered here.

Try Minifigs.me! It allows for creation using almost every part, plus custom parts.
Also try BrickLink, which has a catalogue of nearly every LEGO piece in existence. (For sale!)


text:
LEGO stormtrooper pauldron dimensions
Does anyone know what the size dimensions for Imperial and First Order pauldrons are? I want to make some custom ones.

Based on this information from Brick Owl, the Imperial pauldron would fit in a rectangle of dimensions 2.7 x 2.3 centimeters. The center hole on all capes must be able to clear the neck diameter of approximately 4.88 mm as was quoted here backed up by my own measurements.
If you are looking to make a pauldron for yourself, you might consider finding a trace of the desired pauldron and adjusting the scale until the image is 2.7 cm at the widest. Making a 5 mm hole will suffice so the piece does not fall too low on the shoulders. Hope this helps.


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Where can I download the LEGO RCX 2.0 programming software for Windows 7?
Can someone point me to an active download location of the RCX 2.0 programming software for Windows 7? Thanks!

Possible duplicate of RCX firmware download problem

I can conform that Alberto's answer is a good download link; I've been using it myself. But it should be noted that the USB IR tower which comes with the RIS 2.0 kit is not compatible with 64-bit Windows. You'll need an older serial IR tower and a USB-to-Serial converter to program the RCX using 64-bit Windows.

Use this link for RCX/expansion packs and run the program(s) in compatibility mode: https://www.mediafire.com/folder/718o6673jhpn9/RIS

Yuck. Mediafire links often present the downloader with fake trojan warnings.


text:
PC control Ev3 robot
I wanted to see if I could control my robot with a PC and I wanted to know if there was a way to do it. I have already searched for a controller for the PC and didn't find anything.

Your EV3 allows to send direct commands from the PC to the robot. It offers three communication protocols: USB (needs a wire), Bluetooth and Wifi (needs a dongle). You can start programs, control motors, read data from the sensors, play sound, change the colors of the LEDs, simulate buttom presses and so on. For file transfer you should use system commands, which have a different structure.
The communication is independent from the programming language, what counts are the sent and received data. If your favorite programming language supports the communication protocol, you can use it. You need not start from scratch, there exists code in different programming languages.
You find detailed information about direct commands in this blog: EV3DirectCommands

Have a look on this project on GitHub https://github.com/BrianPeek/legoev3
It uses .NET libraries writen in C# to control and get status of EV3 robot.
There is a video wich explains step by step how to write your own remote control in C# WPF.

I just published tool based on top of this library - https://github.com/sergeyzwezdin/ev3remotecontrol
Feel free to install this with this direct link - http://ev3.zwezdin.com/download/setup.exe

You can write programs with many languages (like Java, C#, Python). Those languages are capable of controlling your EV3 without the need to build and run a program directly on the EV3 brick.
The downside is that you must speak those languages. I'm not aware of independent controllers for the LEGO Mindstorms.
What do you want to achieve? Maybe there's another solution.
Update:
I've posted more info on this in this answer: https://bricks.stackexchange.com/a/8585/7324

Can you please explain in your answer of these languages can control an EV3 brick? What software is required?

authors: Світлана Дорогій


text:
NXT Program doesn't do what it's supposed to do
Ok, so I have this automatic gearbox I have made and I have 2 motors and 2 touch sensors
I want Motor A to spin forever unless Motor B is turning
Motor B should turn around 15 degrees and then brake. The direction depends on what touch sensor is pushed. I created this piece of block code thing (personally don't like) but it looks like it should work but it doesn't.

Motor A spins forever and when B is activated, it spins forever too completely destroying the gearbox :(
Pseudo Code:
If Touch1 == Bumped Then
    Stop MotorB
    Rotate MotorA by 15 degrees
Else If Touch2 == Bumped Then
    Rotate MotorA by -15 degrees
    Stop MotorB
Else
    Rotate MotorB Forever

(I know this is horrrible pseudo code but you get the jist)

What am I doing wrong???

Your text description does not match the picture or pseudo code - motor A and motor B are mixed up. You should fix that for future readers. Also, your pseudo code is not horrible, it is perfectly clear.

You just need to make the blocks match your pseudo code. The missing part is "Stop Motor B". Adding blocks to stop motor B will help.
Also, stop motor B needs to be before starting motor A, otherwise motor A will run while motor B is running.
If Touch1 == Bumped Then
    Stop MotorB
    Rotate MotorA by 15 degrees
Else If Touch2 == Bumped Then
    Stop MotorB
    Rotate MotorA by -15 degrees
Else
    Rotate MotorB Forever


text:
Identification of light and sound part
Found the following car/space craft body this weekend. It takes two AA batteries and has three buttons for different sounds and light sequences. It is marked k8. The part is about six inches long, has LEGO embedded on proper spots but no part number.  I can send a picture if anyone has an idea.  Thank you for the responses it is exactly what is shown in the first answer, and inspectors body.  Now I know.  Next time I will work on imbeddong a pic.
Ted

Welcome to Stack Exchange, Ted. Please embed a picture in your question so we can get you the proper answer. LEGO has made so many pieces over the last 50+ years that identifying one based on a description is nearly impossible. Thanks!

Sounds like electric, light & sound 4 x 20 x 5 insectoid stinger.
Part# top: x239top

Part# bottom: x239bottom

I was suspecting the same ... would like to see a picture to confirm this.


text:
Articulations : which technique to use on small constructions for sturdiness?
So I have been using LEGO® for a rather long time and over the years, I started going towards small constructions. While doing this, I began building rather small robots (Mobile Frames for those who know), between ~8cm and ~11cm or approximately 8 to 11 studs.
Those mechs I build are articulated and I want them to have as many articulations as possible (e.g. a leg should have a hip, a knee and an ankle, not only a hip).
The problem is the sturdiness of the whole construction. I have tried multiple options and the articulations are often either too weak to stay in position correctly or too fragile to support other parts, leading to structure vulnerability and eventually destruction of either portions of or the whole robot.
My question is the following : do you know any compact yet sturdy articulation building technique or any small articulation part ?
Bonus : if you can provide a method allowing me to build more or less on the articulation (not sure if that's very clear).

EDIT : For posing reasons, the articulation needs to have some 'friction' to keep a specific angle.

Should there be any problem with the question (wrong formulation, bad English, need for clarification), please don't hesitate to point it out.

This doesn't actually answer your question, hence the comment as opposed to an answer, but for larger constructions the 24-tooth clutch gear works well.

Well, building tricks are always welcome, especially when it comes to LEGO®.

The AT-ST & Endor (9679) uses cogged connectors (4210884 + 4211803, I don't know if the combination of both parts has a name) for the legs. These connectors are pretty strong for their size, they may be sturdy enough for your model if it's not too heavy.

For bigger constructions and higher degrees of freedom, beam with balls and cups can be used, they allow rotations and movements in two axis. For example, the Beam A 5M Ball/Cup Ø10.2 (they are other similar parts on Bricklink):

For example, General Grievous (75112) arms and legs can be adjusted in many ways:

Thanks, that is already a good start. However, I also need parts moving on multiple axis (like a human hip or shoulder for example). Any suggestion ?

@z3r0 I added the balls and cups, I hope that it won't be too big for your models.

Thanks for the idea, unfortunately those parts are way too big for what I intend to do. Do you happen to know any alternative ? Other than that, the cogged connectors seem a rather interesting concept for mono-axis (is it even English ?) articulation.

You could use the plate ball and cup joints like 6043656 and 4329654 (and a few other parts with balls that will fit)
These parts:

One caveat though, brick #2 from the left does not have much sturdiness in holding joints together. 1, 3, and 6 are good though.

The two small ones in the middle of the picture seem to have size characteristics close to what I'm looking for. Do you happen to know if that specific ball-cup combination has friction (allowing specific poses) ? If I remember correctly, the other ones don't. Also, do you know if the 1x1x1 ball holder also comes in different shapes (1x2x1 like its left neighbour) ?

@z3r0 From experience, the two in the middle do have enough friction, however, there is no 1x2x1 for that piece.

Well, I guess I'll try to find some ball-cup combination somewhere to test their friction. Could you please write the designation of the two parts in the middle ?

@z3r0 14704 for the 2x2x1 socket and 3614 for the 1x1x1 with ball.

In my experience, #5 from the left, when paired with #1 or #6, has no friction worth mentioning.  I don't know about the other pairings.

I think the best technique for building a sturdy Lego structure is to start with a wide and big base and then stack up with smaller bricks. I took part in a Lego challenge and one of the challenges was to build a big Lego tower. So, I decided to start with a big base. Then, I built up with smaller bricks. When I did my test to see which was the best, I found out that a bigger base is better. I also am doing a science fair on which Lego structure is strongest when dropped. I haven't done it yet but I believe that a square base will be the strongest instead of the other bases I have chosen. I love building with Legos but a big pet-peeve is when they break. That is why I am doing my science fair experiment to see which structure is the best. I will let you know when I have my data.


text:
HELP ! Darth Maul stuck in glue?
Not so long ago I got my hands on a box full of loose bricks. There I found an old minifigure head of Darth Maul BUT stuck in his hood! I'm 100% sure it's glue. Is there anything I can do about it ?

If you are sure it is glue, what kind of glue is it?

So you want to separate the head and the hood? Is there anything I can do about it ? is a very open question, so it's unclear what you're asking.

To paraphrase an answer from @awe on a similar question,

You can use some sugar liquid as temporary glue to make the head stuck to the torso. Wait until the sugar is sticky and then pull off the helmet. Once the helmet is loose,  put the head and torso in warm water to remove the sugar glue.

Depending on the glue attaching the hood to the head, you might need to use some other water-soluble glue in place of sugar water glue.

I think that the OP wants to split the head and the hood, it looks like your answer is explaining how to glue the parts, not separate them.

@A.L notice that my glue is temporary, just for enough grip to pull off the hood using the torso as an anchor. It isn't glue for keeping things stuck.

Thanks, I understand now. It implies that the current glue is not too strong.

authors: Stokke 香港官方網店


text:
Identify a space LEGO set from incomplete model
Could someone help me find out which sets these are from please?

https://www.amazon.co.uk/clouddrive/share/manpK0pmTJUynGo8X3P5iBqpYEEIdjnO9Ol2t3dhdNR?v=grid&ref_=cd_ph_share_link_copy

https://www.amazon.co.uk/clouddrive/share/0d8gUy7oMWYN3Z3XiOYGYe8XJojtyCSzWVYKeEC39hV?v=grid&ref_=cd_ph_share_link_copy

These are

6849-1: Satellite Patroller

6808-1: Galaxy Trekkor


text:
What is this piece? 4x4 ring with studs, anyone have a clue for part #?

This is simply a ring with 8 studs on it. Anyone know what it is or what set it's from? Can't find it anywhere on BrickLink. No part number visible anywhere on the part. 1x2 tile on the side for extra size perspective.

It's the face plate for a Lego watch. There's a couple different watches this particular piece could have come from, including this Darth Vader watch and this Luke Skywalker one. I'm unable to find an element or design ID for this part though.

This question is now three years old, but I was looking for this part too.
It's Watch Part, Case Attachment - Bezel Ring with Studs (bb1008).

Note for future visitors: this answer is not a duplicate of the earlier one, as that incorporated information provided only later in this one (the bricklink link).


text:
Need help identifying this Star Wars set from about 2005, white and dark red triangle ship?
I need help identifying this Star Wars set. It was probably released about 2005. The complete kit is about 11 inches long:

It's a dusty 7143 from 2002, but the minifigure is not there.

Thanks so much!  I've got a whole box of lego people so I'm sure I've got the figure in there somewhere.  It's covered with the hydrogen dust of interstellar space ;)


text:
EV3 SPIK3R Mission 2 doesn't move
So I was building Spik3r and I thought I got mission 2 completed. Wheels are turning, legs are moving but the robot just does not move.
It looks like the small wheels should be moving the robot but they barely touch the table surface.
https://youtu.be/2CFU0wDw-j4

It looks like the wheels aren't correctly mounted. As far as I remember you're right that the Spik3r is moving with the small wheels. Can you provide an image or two from the bottom of your model? It's hard to guess what happens just with the video on YouTube.

Thank you!  While taking a photo of the model I notized that the front engine is wrong way. http://imgur.com/PINYPDb

Can you please post that as an answer so that this question doesn't mistakeably be considered an unanswered question?

no, I need to someone answer that one.


text:
What is the minimum required set of parts for Mindstorms?
I'm interested in trying a second-hand Mindstorms kit, but can't afford the full kit. It doesn't need to be the latest version, either. If compatible with my computer, RCX would do.
Is it possible to learn the basics from a subset of parts from the kit? If so, is there a recommended set of parts to do so?

I would suggest at least one sensor. Of course you can program the brick (which version ever) with a motor or two. But that are very limited programs. If you have a sensor, you can create programs that can interact with the environment.
Which sensor is irrelevant in my opinion. For example one touch sensor or an infrared/ultrasonic sensor.

The touch is the cheapest. Also... no accusations, but this looks a lot like my answer.

I would get the NXT brick itself, at least one but preferably two motors, and the touch sensor.
Obviously, you need a brain brick, but you also need a way for it to do something, thus the motors. And if you want to do anything particularly interesting, that doesn't need to be automatic functions only, you'll need a sensor to start different functions at the proper times and in the proper conditions.
You could expand a little by adding the motion detector, but mostly you just need an input, output, and brain.

Is the touch sensor mandatory? Can you create a simple program with only the NXT and 2 motors (and even one)?

Yeah, but that means activating the program from the brick, meaning a lot less options/fun than using a designated inputting sensor, the cheapest of which is the touch.


text:
How can I emulate this wheel from the mowing unit of a ride-on mower?
I am trying to build a model of a specific ride-on mower with Lego and I cannot find a satisfying solution for the wheels supporting the mowing unit.
This is what they look like on the original:

Note that the bottom of the wheel is below the bottom line of the unit that it supports.
The scale on which I am working and my best solution so far is this (the front part):

The wheel nicely extends below the structure it supports, but:

horizontally, it extends rather far from the structure,
it builds up quite high vertically,
the construction is not very robust.

Thus my question is: What other part or combination of parts could I use to emulate this wheel? I prefer if the required parts are easily available in red, but I appreciate other suggestions as well, as I may have missed something that I can do with the parts at hand.

My first thought would be to try and build this using 2x 32017 - Technic Liftarm 5 Thin and the following combination of a 1/2 bush and a tire (same tire you have on the wheel on the black part of your build, though the front tire might fit too).

If you use a 2L axle (in red!) this should look quite sleek. Not sure if the tire is going to be tall enough to support the mower, but it would definitely be sturdy, given that you're using Technic.


text:
Can anyone identify this set?
https://www.gumtree.com/p/other-baby-stuff/various-bits-of-lego-all-for-%C2%A35/1183678235
Can anyone identify this set? Is it even genuine LEGO?

Welcome! This collection of pieces might contain some LEGO pieces, but is mostly another brand. The bottoms of the bricks and plates have patterns that are not typical for LEGO, and LEGO does not make a large wedge plate like the light-grey one on the right. Furthermore, LEGO did never make a large tree stump and tree with face as shown in the middle of the picture. As such, even though the seller claims this is "LEGO", it is not.

This collection of pieces might contain some LEGO pieces – For what it’s worth, these pieces have a strong similarity to existing pieces or are very close replicas.


text:
Are LEGO tires natural or synthetic rubber?
LEGO is the No.1 tire maker in the world by number of unit. It produce the same number of tires in a year as both Michelin & Bridgestone together, the 2 biggest tire manufacturers.
A "real" vehicle tire is made of a mix of Natural Rubber (coming from a tree: Hevea Brasiliensis) and Synthetic Rubber (coming from oil). Is this the same for the LEGO tire or is it only Synthetic rubber that is used?

While the other question is not an exact duplicate, the answers cover this question also.

@chicks Perhaps this is semantic, but a duplicate is pertaining to the question only, not just applicable answers. Answers thus aside, this isn't really a duplicate.

@chicks Also, the bands aren't made of the same rubber as the tires nowadays, so the answers aren't applicable.

@CalebWoodman The (your) accepted answer from 5 July this year  states "Tires and elastic materials found in some LEGO sets are manufactured from Styrene-Butadiene Styrene (SBS)"?


text:
Where can I find a copy of read_binvox.cc
Can you upload your read_binvox.cc please?
I tried to find out some on the net but at each time I would like to paste the program on my code blocks the program had an error (0xc000007b).

I've updated these broken links assuming that you are referencing this answer: http://bricks.stackexchange.com/a/3075/708 In the future, it's simplest to just leave a comment on the answer when requesting updates like this.

This software is now available here:
http://www.patrickmin.com/binvox/read_binvox.cc


text:
Which LEGO AT-RT is this?
I made a LEGO AT-RT with the help of a video but I can't find it now. It looks like a clone scout walker but green and a bit different in design. I loved that AT-RT. I hope someone can help me find it. The legs look like the legs on the LEGO 75002 Walker:

If you watched this on youtube, how about digging through your history?  https://www.youtube.com/feed/history

A quick search found these two video's of AT-RT's in green
https://www.youtube.com/watch?v=c0sFAreiaPc
and
https://www.youtube.com/watch?v=Cbc_k_GwfRw
this AT-RT is also very nice and greenish (no video)
https://www.flickr.com/photos/legoarts/4917477074/in/photostream/

What i seen is bigger but thx for the help :D

This may be the clone trooper you are searching for...

Are you thinking of the 20th Anniversary AT-RT?  The legs are very similar but the head looks fairly different.  It is grey with sand green and tan accents.  The set number is 75261.


text:
Turnover share attributable to AFOLs
Traditionally LEGO has been known as a kid's toy, but there is a growing community of AFOLs (Adult Fans Of LEGO).
How big share of LEGO's turnover is attributable to AFOLs?

Turnover can mean quite a few things; do you mean how long a person is actively buying LEGO bricks?

@Mark Stewart: Revenue, money on the income statement.

OK, pure accounting definition, not inventory.  I would look at the financial statements but since it is a private company, that would not be available.  I would then be forced to look at shelf space at stores to see how much space is dedicated to young age groups vs. older, and pure building sets (non-themed)

I'm voting to close this question as off-topic because this information is controlled by The LEGO Group and not something we have access to.


text:
EV3 program refuses to work
I downloaded a 67KB program into my EV3 block. However, the program refuses to work. The EV3 says "Main", the name of my program, but it does not respond otherwise. What is the problem, and how do I fix it?
Thank you.

Where did you download the program from?  A URL would be nice.  Does your EV3 work with other programs normally?

Can you please send a screenshot of the program if you can see it? On Windows 10, using Win+Shift+S will allow you to crop out a part of your screen and save it as an image. You can then add the image here

Try adding a wait block in front of the program and at the back. :)


text:
Why are Technic holes slightly smaller than studs?
We know that Lego studs almost never should be placed into Technic holes because studs are slightly larger and will stress the hole.  However, why is there this discrepancy?  Surely when Lego created Technic they would have considered this possibility.  Is there simply not enough room for the hole to be slightly larger?  And if Technic holes were never meant to accommodate studs, why didn't Lego make the discrepancy larger to more naturally discourage such a mating?

I'm going to guess that when axles were first introduced Expert Builder was not a thing and the hole size was based on making a convenient path through the 4x2 brick that was the only thing with holes in it. Those holes do not work with studs, they are too large. Even the "new" 1x2 bricks with hole type 1 and 2 didn't accept studs (and the gap/slot at the top prevented it). That allows axle slop, but with the huge parts at that time this was not a problem, in fact it meant low-precision models worked just fine.
In 1970 there was the "Gear Supplementary Set" and "Gear Set with Motor" that had the first mention I can find of axles and gears.

Note that the set is labelled "Universal Building Set" and TLG appear to agree that "Expert Builder" appeared after that in 1977. In 1976 when the 695 "race car" was released it used second variant red axle stops and 1x2 brick with hole type 2 but wasn't Expert Builder.
The 1x2 brick with hole makes it clear that putting a stud in the hole was not possible (this may be the reason for the slot?)

AFAIK those bricks and axles are compatible with current Technic (they work IME but the dimensions might have changed a tiny amount and I wouldn't know)
Then we can look at TLG's current view of their history and see this from "The beginning" of Technic

In the early 1970s, Jan Ryaa was one of the very first LEGO designers to play with the idea of building cars, using large square LEGO Mobil bricks in yellow, red and blue with white cross-axles and cogwheels. These were used for showroom models and were not planned as production models, nor intended for sale.

I suspect he was using the production axles and bricks, but trying to make more mechanically accurate/challenging models and found the giant gears and 4x2 bricks a bit useless.
Brickset's history of Expert Builder makes it clear that by the time that theme was launched the "modern" Technic brick was in production. All four models used those bricks, and the hole were as compatible with studs as they are today.
Again, I can't find an official statement from TLG on this, but I will guess that since Expert Builder used existing axles they just ran with that size, only tightening up the hole a little to make their tiny-toothed gears work properly.

EDIT: Answer's wrong, but I'm keeping it here because I don't like to hide from mistakes.
The articles you listed don't say that studs are too large to fit properly in the Technic hole; they say that the hole is in a slightly different position. This causes an alignment issue on the tops and bottoms of the bricks, which leads to stress if bricks are attached across both studs on top. As for why LEGO chose this design, the second article you mentioned answers this: "The Center point was moved up in order to accommodate the additional plastic needed around the Technic hole so that a stud can still fit in the bottom of the brick."
EDIT2: I have a theory, actually. The slightly smaller holes might be a compromise, to allow for Technic bricks to fit a stud on the bottom of the brick without pushing the top too far up.

I'm asking about the hole size, not the position. You didn't read enough into the Lego presentation. Slide 12 says: "Technic holes are slightly smaller than those of System.  You can connect a single stud into a Technic hole and a child can still take them apart. Any more than that and the resistance becomes too great and there is the potential for elements (and children) being stressed." The accepted answer from my first link also mentions the size discrepancy.


text:
I have a LEGO instruction book with the front identifying page missing. I am trying to work out which set it is. Yellow and black sea plane and boat
The LEGO set looks like a Creator set, mainly yellow bricks with many different small builds. Biplane, Speed boat, submarine, vehicle ferry, yacht, oil tanker. The photo of page 3 is attached.

Any ideas?

These instructions are from 4505-1: Sea Machines

Complete instructions book  (PDF)