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Brick Wall psychology: PAB cup filling strategy?
Since I don't live next to a LEGO store I don't often have the opportunity to stand in front of a Pick A Brick Wall. Recently, I filled my large PAB cup for the second time. When I browsed the wall, I found several pieces that fit into my current (or near future) projects. I was aiming for small parts, since the price on Bricklink would be at least some cents each.
Here comes the question: I needed some trans-clear 1x2x2 panels. I took some, walked back and forth, put some more into the cup, and ended up with 43 (!) of them. But I was sure that I only had 10, maybe 15. Am I crazy? How can I so dramatically underestimate the number of those panels? Do you know in advance what to put into the cup? What is your PAB cup strategy?
The picture shows the filled cup.

And this is the pile of the mentioned panels:

Thank you for the inspiring answers. Unfortunately, I can only accept one.

My Pick-A-Brick Strategy:

Are you interested in building this months' model?  If so you should pick out all of the parts for that first.  Put the big pieces in your cup now.  Hold the tiny pieces until you're ready to fill in gaps.
Put things together that probably belong together like turntables.  This is key if you don't want to end up with more of one half than the other.
Stack blocks and other things that stack naturally.  This can take a lot of time while you're in the LEGO store, but it is worth it if you are trying to squeeze all of the wasted air out of your cup.  Having things stacked from the store will also make it easier to sort out your cup when you get home.
Fill in the remaining spaces with small things like LEGO "dots".  The dots are great for filling in air gaps in your cup.  You will almost always find some colored dot on the wall.  And they also come in handy when building.
Ask for your lid to be taped so it will make it home without spilling all over the car, bus or train.
It is good to decorate your cup while you've got it at home so there's no confusion at the store about whether your brought the cup from home or not.  Sharpies or other permanents markers will personalize your cup for a few years.

Good luck!

You aren't crazy. In my experience, the PaB wall ends up having only a handful of parts that I'm really interested in, so I end up getting a lot of certain parts.
I find myself walking back and forth adding the same parts that I know I already have a bunch of just because nothing else looks particularly interesting to me.
Several years ago, I filled up a small PaB cup and ended up with 62 of those trans-clear panels, so you're at least doing better than me. :)

In terms of strategy, I've found it helpful to check the inventories in advance and decide if it's going to be worth having a cup full of those parts. At this point, I usually don't fill up a cup unless there is a part that I don't mind having a whole lot of (e.g. 1x2 bricks in a rarer color that I like). If I fill up a cup it tends to look more like this now:

First of all, thank you for resolving my doubts about my mental state :) I looked up the few sources to get information about the content of a brick wall in advance. The quality varies piece by piece, so I will bring my cup whenever I make a trip that brings me close to a LEGO store. I could really try stacking bricks next time. You seem to have optimised the technique.

Everyone has different strategies because everyone builds different things. Last time I went to the lego store I got almost all of the same color(orange) because I wanted to make a decoration in my room. I also picked up some parts I thought I would use in cars. Other people might be thrilled to see pieces that can be helpful in landscaping. One thing that is consistent is the fact that the smaller the piece the less air you buy. If you can see a gap I would put studs to fill the gap to make the most out of your cup. Also, the store I go to in Castleton will tape your cup shut if it is over flowing(don't be rude and make it way above the brim). The divot in the top of your cup isn't just for decoration. It can hold a little bit of bricks. I personally never plan my visit to the Lego store around the PaB wall, but sometimes you can score a deal, especially since there isn't shipping like bricklink or ebay.

My strategy usually goes something like this:

Bring a pick-a-brick cup from before! If you ask, they may give you a $.50 discount on the price for not taking a new cup (at least in some US stores).
Set aside what I need before I put anything in the cup.
Determine how to assemble them into small-ish structure that will fit in the cup.
Find some little filler pieces that can go in between the assembled chunks.
Make sure the bottom ring is full, as the larger pieces will not go down that far.
Start layering up the levels of structures and fill in the spaces between with filler pieces. Because the cup gets wider at the top, assembled structures usually fit best in layers.
When you get to the top, build something to fit in the top of the can, and put the lid on.
If the lid doesn't fully snap into place, they usually don't mind and will tape the lid on.

Tip: If you want to buy multiple cups, you can empty the first one out into a bag. Then you can reuse the cup and get the $.50 discount again. Or if you have them, just bring multiple cups (may be store dependant).

Thank you for the tips. One interesting observation : Handling of the cups seems to depend on the country. In Germany, we get a bar code on the cup. The code is scanned at every visit in the store, VIP points automatically go to the associated LEGO id. And we can have the reduced price only once a day.

There aren't any barcodes like that on the cups in the US.

They always have more pieces than displayed. Ask for Pick a Brick selection baseplate. They will have all available pieces attached to a 32x32 baseplate in the back. Staff can bring you pieces you need and aren't displayed on the wall. I recently got a cup full of light grey 1x2 masonry bricks perfect for the castle Im building.

This is true. When I asked, they showed me a bucket full of previous PAB items.


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Classic 9V battery box current limiter?
Recently I disassembled a classic 4760c01 Electric 9V Battery Box Small Complete Assembly to see what was inside.
Battery Box:

Disassembled:

In the switch component, we find what appears to be a current limiter:

It slides right out if you use a pin or something to push it out.
Here is a closeup on it with one of the other pieces:

It's a small metallic looking disk with a black edge and some divots on the faces, and no identifying or informational markings.
Based on usage experience, I believe it limits the current to less than what a 9V battery can actually output, but I don't know for sure or how much that limit is. I've search around, but wasn't able to find any information on the current limiters in the battery boxes before the one from 2006.
Does anyone know what the current limit of this old battery box is? Or know a way to discover what the limit is?

The short answer is about 150mA.
Electrical Characteristics
From the limited testing that I've done, the component you pointed out appears to be a positive temperature coefficient thermistor. Here's how Wikipedia describes their use as current limiters:

When first connected to a voltage source, a large current
  corresponding to the low, cold, resistance flows, but as the
  thermistor self-heats, the current is reduced until a limiting current
  (and corresponding peak device temperature) is reached. The
  current-limiting effect can replace fuses.

I only have a basic multimeter and a few fixed voltages handy at the moment, so I'm not able to derive the precise characteristics of this device. I was able to measure the following:

Open circuit resistance is 4 ohms
Short circuit current at 12V is ~50ma.
Short circuit current at 10V is ~50ma.
Short circuit current at 8.3V is ~60ma.
Short circuit current at 5V is ~100ma.
Short circuit current at 3.3V is ~120ma.

The tolerances on these parts are pretty loose, but for mine the maximum it can supply consistently in series with a motor is about 150mA. If I keep current above this for long, the thermistor begins to heat and total current decreases due to the limiting.
It might seem odd that the max constant current I was able to sustain is greater than the short circuit current, but this is due to the fact that this component is effectively limiting the amount of power it dissipates, and not the amount of current it passes. Power is the product of current and voltage, so because some voltage is dropped by the load, it is able to handle a current higher when loaded than it is able to when shorted.
Physical example
As a point of reference if milliamps aren't very familiar to you, in my testing I was able to cause the clutch gear (60c01) to slip indefinitely on 43362c01 with the thermistor in series.

This drew about 100mA for me. So, you can drive most of the lighter 9v parts just fine. The current limiting will kick in at about half the stalled current for most of the motors. Larger PF motors, and especially the RC buggy motor, will not be able to reach their full potential with the overload protection in place on this battery box.

Interesting. I'm a little bit confused about the 150mA thing though. Your listed short circuit currents and physical example seem to suggest it's less (~100mA?). Have I misunderstood something?

I've added an explanation to the end of the electrical characteristics section. I'm fairly confident that this is due to the fact that the thermistor sees a lower voltage when there is a proper load in use.

source: Stack Exchange

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

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Is there a tool that can consistently remove hundreds of 2x2 Tiles?
I have hundreds of 2x2 Tiles that I use to create LEGO City scale footpaths and floors. They are arranged in a grid on baseplates in a similar way as shown below:

Recently I had decided to rebuild the entire city and I've struggled to find a way to easily remove all the tiles. For some of the larger baseplates, I can make it easier to remove tiles by slightly bending the plate so that they pop out.
I have been using the chiseled end of the orange brick separators to remove the pieces. They work perfectly when new, unfortunately the chiselled edge is quite soft and it bends quite easily, becoming almost useless over time.

The other end of the brick separator is even harder to use and I have tried the old grey brick separator also.
Do you have any recommendations for tools (LEGO, 3rd part or non-brick based) for removing these pieces?
I would prefer not to use anything metal or that may damage the bricks.
The tool should also be comfortable to use for removing many pieces.

I suspect that anything that doesn't damage the bricks would need to take damage itself.

If that is the case, I wouldn't have a problem with a disposable tool that could do the job.

I would consider brick separators disposable.

At the rate I've gone through them already, I would prefer not to use them.

Given that such tiles come with grooves since decades, what is wrong with fingernails?

I have fairly short fingernails, I do use my nails if all else fails but I always come across tiles which border tiles on two sides such as this tile with the blue cross.

Try using the orange brick separator upside down. This is a trick I learned from someone who professionally works with LEGO. The lower angle makes it easier to go under the lip of the tiles and it is much less damaging on the brick separator, as you are more pushing and sliding rather than digging and prying.
To be clear, instead of holding the brick separator with the LEGO logo and the Technic pin on top, turn the brick separator upside down. You will notice that this transforms the angle of the tip into a little ramp that you can slide under the lip of the tiles.
For flat tiled surfaces, like the one on your picture, the upside down brick separator works very well, with very little (if any) damage to the brick separator. However, notice that this method also requires more space, as the brick separator needs to lie more flatly against the surface. For tighter spaces, like when you have a wall around the tiled surface, you would still use the brick separator right side up, as the different angle of the tip requires less space for removing tiles. Once you freed up enough space to lie the brick separator more flat, you may turn it upside down to work on the rest of the tiles.
The brick separator really is a well thought out tool that works for almost all scenarios when you need to separate LEGO elements. If you find it not performing so well one way, try from another angle, or upside down, or two brick separators together, and you will likely find it working much more efficiently.
EXTRA TIP: For very tight spaces, the LEGO minifigure accessory crow bar works very well for removing tiles. The tips on the two ends are different, and can be used at different angles. The only issue is that the tool is quite small, and for people with large hands it can be a bit difficult to maneuver.

That's the way I've been doing it so far, I agree it works much better than the other way. If there are two adjacent tiles I will always try to place the tool under both of them to be more efficient and avoid wearing the tool. I have also used the minifigure crowbar and I've tried it again to see how it works but it's a bit slower than the separator.

I sometimes use the other side of the separator (top side) to pry out the tiles once they have been loosened.

I haven't tried these myself, but in the computer repair world there exist tools with similar purposes.
Spudger:
Flat edge (the right-size comes to a flat point):

Knife-shaped edge:

Opening Pick/Guitar Pick:

NOTE: A number of companies manufacture these, but you would need to make sure you get ones that are sharp-enough to catch the lip on the tile.

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How to estimate the pieces of a construction from just one photo?
My teacher is handing points to anyone who could guess how many pieces are in the construction shown below. I’d say there are about 350 but most people are saying thousand or more, which is insane to me. The only clues are that it is 43 cm long and 24 cm wide.

How can I best go about such a task, i.e., how can I best estimate the number of pieces from a single photo?

It's not a set. Only the person who designed it knows how many pieces are in it.

I get it, but I just want someone with an actual knowledge on legos to make a good guess

Welcome to Bricks SE. I took the liberty to make the question more general. On Stack Exchange we hate to do your homework for you, but we may tell you how to do it yourself.

What have you tried so far? I think your teacher would be more interested in the methods you've taken to work out the problem as much as the final guess you give.

She sent us a video as well, showing all sides of it. She just wants us to guess; the one who gets closer to the answer will have the extra points. So far I've meticulously tried to count (approximately) the pieces and I'd say there are about 619. Tomorrow we'll know who's won.

Is it hollow or massive?

So...who won? Did the teacher give an actual full total, or her own guesstimate? Was it more about methods of estimation, or something else? The suspense is killing me!

In this case, knowing that the model is 43 cm long and 24 cm wide isn't particularly information. It's very difficult to give a rough average of parts when all the parts vary in size and the model isn't in a single primitive form (cube, sphere, pyramid).
With the exception of the eyes and mouth, this particular model appears to be built almost perfectly symmetrically. If you can imagine a flat plane bisecting the model in two vertically you can count the bricks on the visible side (minus the details) and duplicate that number to get a rough guess.
The model could be mostly hollow, but there are bound to be certain pieces that you don't see on either side of the model that add to the physical structure. In particular the bricks that attach the eyes and mouth and the SNOT details on the arms.
In some places it can be a bit hard to visually count the bricks (particularly around the mouth). You can use basic image editing software to sharpen the image and get a clearer idea of how many parts are used.
There are also some unusual aspects in this model where three pieces have been used where a single 2x4 brick would do as shown at the top of the front side of plant pot.

Couple of observations:

I do not understand your teacher's motivations in giving out this exercise. There is too much guesswork involved to make the exercise of any educational value. Example: there is no visibility into the internal frame of the main "stem" of the cactus, which is clearly a SNOT build made of several layers of plates mounted on an (invisible) core supporting structure.
Luckily, just putting in a guess is going to give you points, as the exercise is "My teacher is handing points to anyone who could guess how many pieces are in the construction shown below". Nowhere does it state that points are only handed out for correct guesses, so just guess any number and you should be fine.
You have no insights into the back of the structure. This could be a mirror of the front (as suggested by @Ambo100) but it could also be constructed differently, without any way of telling. Similarly, you don't know if the pot structure is hollow or solid, or if the reddish brown earth is one plate or several layers thick.

In conclusion, either the teacher is trolling you, or you are trolling us with this question.

Probably just a fun extra credit exercise

My son had a similar exercise this term to "Estimate the number of people in a crowd" with a fairly poor quality, black and white photo of a football stand. The goal was more about showing reasoning, and realising what was a reasonable estimate. There is educational value in this sort of task :)

@Zhaph-BenDuguid At the same time, people are all roughly the same size, and generally distributed rather uniformly in a crowd, so there are approaches which can leverage that. Neither applies to a Lego construction, so I see much less value in this guessing.


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Can you interchange System and Technic LEGO?
My grandson would like to motorize his LEGO builds. Does the Technic motor pack only work with Technic LEGO or can he mix it with the regular sets that he already has?
What should he start out with?

Hi amanda, welcome to Bricks Stack Exchange. There are many ways to add motion to LEGO bricks, could you be more specific about what you would like to create?

I assume by the Technic motor pack you mean this:

The straightforward answer is in my opinion "no", the pack does not contain enough pieces, nor do System sets contain enough unless they were explicitly designed to have moving parts and allow motorization (e.g. the carousel or other LEGO expert fairground sets)
You need "some" LEGO Technic to allow for moving parts. The LEGO Technic itself is then in many ways compatible with System Lego.
The amount of Lego Technic your grandson will need depends too much on what he wants to achieve to give a generic answer.

Agreed. Specifically: most System kits use wheels that can't be motorized. If you have wheels with cross-shaped connections, they can accept an axle which can be driven by a motor. However: the quantity of technic parts in System kits has been increasing (in my subjective opinion) over the last 5 years or so, so it's possible that a kid would have enough pieces to do something useful with a motor. It strongly depends on which sets one owns.

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How can I repair a red 12v train motor from Set# 7730?
I have a LEGO 7865 Red 12 volt train motor from a LEGO 7730 train set.  The motor has stopped working as it has been dropped on one of the wheels.
How can I open the motor case to effect a repair?

Do you want to open the train unit or the motor itself?

I need to open the red case of the motor itself. I think that one of the gears has been forced out of engagement, maybe the shaft is bent,

According to Bricklink,  Set # 7730 has this motor :
bb12va Electric, Train Motor 12V Modern Type I with 2 round contact holes
For disassembly and repair you can look at this large post with pictures on Eurobricks by Andromeda

Unfortunately, repairing it will not work, if the shaft is bent, as the wheel would just fall off again.

Replacing shafts is something routinely done on non - LEGO mechanisms. Why wouldn't it work here, if it's bent?


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How can I program a motor to rotate towards the source of sound?
I have 3 sound sensors and a motor connected to four ports of the same brick.
My motor should rotate by some angle towards the highest sound detected by the sensor, and now I'm wondering how I'm supposed to do the following: write an infinite loop for continuous detection but once true the motor keeps on rotating for the same angle.
Is there some way to rotate for a certain angle, stop and then wait for the next sensor to detect the highest sound and then move again for the same angle and wait again?
I am using EV3 brick with NXT sound sensors and a large motor,
so far my logic for detecting the highest sound detected by the sensor is working but  I am facing problems controlling the motor.

I have attempted to re-write the question as best as I can. Which brick are you using, the EV3 or NXT brick and are you using the standard programming interface? What have you tried so far and what works?

@Ambo100 i have edited my question please have a look

Thank you. I'm still trying to visualise what it is you're trying to achieve. Is this diagram accurate? The M representing the motor with the three sensors surrounding it? Are you trying to make the motor rotate to the sound source or towards the sensor that picked up the loudest sound?

What kind of motor do you have available? Servo? Stepper?

the motor is standard motor provided with ev3 kit it is servo motor

@Ambo100 yes the motor should rotate towards the loudest sound picked by sensor, the motor has a pointer which rotates towards the sensor which detects highest sound the senors can be in series and motor on one side, like all sensors on one side of triangle and motor on the opposite vertex.

"A motor connected to four ports of the same brick" What?? Please be clear since nobody can really give a definitive answer to your question!

And there are three servo motors included in the kit: two large ones, and one smaller one. By saying "it servo motor" you're not helping us in any way, because you are lacking the most important details, like which one. Just imagine you were sending all this information to a stranger in real life. That should help you.

To detect the highest sound you can use this code. It would help if you posted a picture of your bot, but with a general idea here you go:
FOREVER loop
{

if RightSensor > Left Sensor :
    if RightSensor > MidSensor :
        highest = RightSensor
    else :
        highest = MidSensor
else:
    highest = LeftSensor

if LeftSensor is the highest:
        turn left
if RightSensor is the highest:
        turn right
if MidSensor is the highest:
        do not turn
}

thanks for your answer if it would have been in simple code i myself would have resolved it, i am working with default ide of ev3 which uses blocks not code i have found the solution will post it soon..

@user3667576 Can you share the EV3 code snippet for that? I'd find it very useful!

I don't understand the question.  I do understand the quandary of trying to write code in the blocks available in the EV3 IDE.
I suspect the questioner really wants something like, given 3 sound sensors, how can I build and program a motor to point to the loudest sound.  One could imagine a turntable with the brick on the platter and 3 sensors mounted 45 degrees from each other.  Rotate until the middle sensor is loudest.
A part of the solution would be to determine which is loudest. See Vikhyat's psuedocode. This is a snippet to do that.

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


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Colored balls detectable by EV3 color sensor
I'm looking for large balls in standard Lego colors that are detectable by the EV3 color scanner.
So black, white, green, brown, yellow and blue and between 5 and 10 cm.
I'm aware of the Duplo balls:

But they do not seem to exist for all the 7 colors.
Are there any other larger balls from Lego in the standard colors?
Is there any third party offering them?
How much can the colors differ from the Lego colors so that they are still detectable by the EV3 color scanner?

There is an interesting discussion on this on the lejos.sourceforge.io forum.

the calibration values for the NXT sensor are set in the factory and seem to be different for each sensor (which implies that there must be a reasonable amount of variation between different sensors). On the NXT the RGB values are true raw values and the calibration adjustments used to identify Lego colors are made in the leJOS driver.

But on the EV3 there is no calibration, and the sensor RGB mode

is not well documented and was not exposed at all in the first version of the Lego software...So the bottom line is I doubt if anyone outside of Lego (and maybe NI) knows if the RGB values are raw sensor readings or if any sort of calibration data has been applied

So it doesn't sound like you will have a consistent set of data anyway - I'd suggest just seeing what coloured balls you can get cheaply and just trying them.


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Lego Mindstorms education NXT 9797 software for a MacBook Air
Where can I find Mac OS compatible software for the Lego Mindstorms Education NXT Base set (9797)?

You can download software for programming the LEGO Mindstorms NXT robots on macOS directly from the LEGO Mindstorms website.
The software is packaged in an ISO image, and there are instructions for how to install it also available on the same page.
Keep in mind that this is the retail version of the software, designed for use with the 8547 NXT 2.0 set, not the education version. The programming functionality for both sets will be the same, but the retail software does include some features specific for the 8547 set, such as building instructions, and does not include some features that the educational software does, such as data logging.


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How can I combine multiple PF XL Motors
I have built an enormous and heavy Lego RC tank, driven by 2 XL Motors, connected to a subtractor, one motor is for steering, the other is for propulsion. Despite having already geared down the motors to provide more torque for the vehicle, the sheer weight of the machine is too much for a single XL motor, even geared down, so the gears tend to grind a bit,  but I do not want to gear the motors down any more since the vehicle already travels incredibly slowly. I am wondering if combining two XL motors for propulsion and steering (resulting in 4 XL motors in total) will give me more torque whilst retaining the same RPM.
Thanks,
Nick

This question likely already has answers in the form of https://bricks.stackexchange.com/questions/8867/how-to-get-double-the-speed-from-2-regulated-ev3-motors/8868#8868 and https://bricks.stackexchange.com/questions/1327/whats-the-best-way-to-link-two-or-more-lego-power-functions-pf-train-motors?rq=1, even though those questions have slightly different scope.

Maybe you could provide some pictures. Then we may help in your particular build. At the moment, the question is rather generic and a possible duplicate of other questions.

The XL motor is already pretty powerful so you do have to consider the ultimate strength of any plastic gears involved in the drive train particularly when it is well geared down. Using two motors will tend to compound the gear strength issue. As others have said some pictures of your tank and its drive system would be very helpful.


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What is the length of a DUPLO train bridge?
I'm trying to plan a DUPLO train track layout to order but I currently don't own any pieces. I'd like to include a bridge like the one in set 3774, but I'm unsure if it will fit my layouts.
Can anyone tell what's the length of the bridge (it seems to be made up of parts 6393 and 6392, two of each) in DUPLO studs?

From the looks of it (by inspecting the image on Bricklink), the red bridge girder is 10 Duplo studs long.

Based on the layouts from this answer, a half-bridge seems to be 2 straight tracks + 1 quarter-circle (split mid-track at the end, because the middle of the bridge is centered with the crossing track below it).
From this guy's measurements, a quarter-circle of the newer DUPLO tracks is about 18x18 studs. Straights are 8 studs long.
So, a half-bridge should be 32 studs (16+8+8), or 4 straight tracks. The full bridge would be 64 studs, or 8 straights.
Note: I don't have the pieces to confirm these measurements.
Note 2: I now have the pieces and can confirm these measurements, as shown in the picture below.


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Are there any bricks to make big size robots?
I found a robot called meccanoid 2XL but it's humanoid robot and I think it's hard to control it. I am looking for a robot like the pic, that stands on wheels instead of legs, and has about 150CM height.

Are there any bricks for such robot? Or maybe bricks in smaller size that I can build it exactly in larger size(I mean model it in solidworks and then 3d print it in larger size)?

You can build up Lego bricks to create large structures (much larger than that, certainly), but they are fairly heavy, so you might have issues motorising it sufficiently to move. An alternative would be to build a low level motorised frame, with a lightweight decorative cowl made from some other material connecting to other functional parts. If you're doing that, though, the use of Lego might not be the best choice for the base

The question about how to build and control a large humanoid robot is too broad. What have you tried so far, what specific problems do you have? Are you sure you are asking about LEGO?

@Aziraphale: I didn't know here we must ask question specifically about LEGO! I thought all the bricks or such things could be considered here!
BTW, if I want to ask better question, I need to build a cheap prototype, and this is my first experience. I don't know how to build it's skeleton and how to cover it by what material?

What have you tried so far? What works and what doesn't? What exactly do you want to model in solidworks?


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What sets have the best price per part ratio?
I am trying to get the set LEGO makes with the best price per part. I could spend the next hour calculating it or I could ask someone who has already done this.
To clarify, I am buying any new set at retail price from LEGO. I will wait until there is a good promo running, but wanted to know ahead of time. I don't care about the pieces just the price per part.

what parts are you looking for? makes a big difference.

Are you really willing to buy a set based on the price per part? That is like judging a movie based on its length. What do you mean by "A good promo"?

Aziraphale thanks for commenting, but that really doesn't help answer my question. My example of good promo is irrelevant, and I will obviously weigh into my getting the set how much I like it as well.

Not going to argue with the reason for the request, but here are some options that give (close to) the best price per part:

Any classic brick box typically gives you a less than $0.05 per part price. Getting those on discount can get you even lower. (E.g. 10704 when on sale at WM in the US was $20 for 900 bricks - or a little over $0.02 per brick).
Special sets not for regular retail (marked as Gear on Bricklink.com) have a good price per part ratio. 40174 Chess set has over 1400 pieces and retails for $55 (~$0.04 per part). Only available at LEGO Shop at Home and LEGO stores. Similarly for the What Am I? game - 540 pieces, currently on sale for $24, so also ~$0.04 per part.
Some smaller sets, especially when on discount, also have great price to part ratio. 100-120 pieces in a $5 set gives a price to part ratio of $0.05 or better.
On the other end of the spectrum: LEGO has released quite some large sets recently with great price-per-part ratios. Sets like Destiny’s Bounty (2300 pieces for $160, Ninjago City (almost 5000 pieces for $300) and especially Saturn V (almost 2000 pieces for $120) are expensive but proved tons of pieces.
Clearance discounts (especially those of 70% or more) are great opportunities to buy high piece-count sets for little money. For example the Imperial Assault Carrier from 2014 was available at WM clearance for $30 or less, and has 1100 pieces.

Brickset has a cool feature where you can see all sets in a Theme or in a given year sorted by the Price per Piece count. First, go to the page for the year you are interested in (I chose 2017). Then use the sorting dropdown to pick “Price per Piece (US)”. You can see that this largely validates my points above. Note that the list starts with many sets that do not have a price per piece in US dollar available (promos, limited release sets, sets not available in the US etc.) You will have to scroll quite far down before the proper list starts.

I didn't realise how much cheaper LEGO is in the USA compared to the UK. $120 for the Saturn V? In the UK at retail price it is £109.99 (almost $150). Either way it has a generous part:price ratio.

@Ambo100 : two reasons: 1) Bexit, 2) US prices are before VAT. So $120 US is actually $130 after our typical 7-10% sales tax. European VAT tends to be much higher (15-20%+) so for a tax-free buyer the price is fairly comparable.

I didn't see the VAT added when I tried adding a product on the LEGO shop site to my basket so I assumed the VAT was included.

VAT only gets added during checkout after you have specified your address. And if you don’t have a US address, it will not add tax.

Oh I see, I assumed that the US had a fixed VAT rate across all states.

Nope, every state has its own sales tax rate, and then most municipalities add their own tax on top of that. Where I live state tax is 5%, and local tax adds another 2%. There are states with NO sales tax as well (New Hampshire is an example).

Phil B has some great info posted, but here are some additional things to think about.
Anything can go on clearance, and obviously adding 50% off will help the price per piece. However, sales and clearance are unpredictable in that you don't know when the sales will occur or what they will be comprised of. So I would skip doing calculations about hypothetical sales, unless you have a 70% off set in your hands.
Phil B made no mention of the Lego Pick a Brick wall. This is, for many types of pieces, the absolutely most cost effective way to get a lot of parts. If you live near a LEGO store, swing by once a month or so and load up on bulk parts.
He also talks about 'classic type' sets. This would be the Creator Line sets, which have the added bonus of having a lot of good basic pieces that aren't too specialized. Look at these first, they are going to be your best bet.
The really large sets tend to be very cost effective too, but it might not be in your budget to drop $150+ per box.
If you really want a lot of LEGO cheap, go buy 50 lb. used lots off of e-bay. Even after you pick out and throw away the inevitable mega-blocs, the price per piece is still way lower than anywhere else.

Thanks for showing some alternatives to buying sets. I always wondered how cost effective pick a bricks were.

Great suggestion. Just remember that 1) there is a very limited selection of bricks in a Pick-a-Brick wall (20-30 different parts tops), and 2) the larger the part, the fewer you can stack in a cup, which raises the price per piece. At $16 per cup (US price for a Large cup), you need 300 pieces in a cup to hit $0.05 per brick or less. That’ll work fine for 1x1 plates, but good luck sticking 300 2x4 bricks in a large cup ;-)

Kind of a joke still very cost effective by cost per part. Small pins weight just 0.1g (per bricklink https://www.bricklink.com/v2/catalog/catalogitem.page?P=4274&name=Technic,%20Pin%201/2&category=%5BTechnic,%20Pin%5D#T=P), so you can theoretically buy used 1lb = 4500 parts for 5 USD - that's 0.1 cent per part, 20 times cheaper than cheapest set in accepted answer :-)


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

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

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

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

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

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

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


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Identify LEGO Dimensions pack
Can you please help me figure out which character this build pack goes with?
The bag has a copyright date of 2007. I know the number on the bag doesn't matter but I noticed the copyright date might help narrow it down a bit.
I've also included a picture of the set laid out so you can see which pieces are in it.

Regarding the copyright date, in this case the date makes no difference because the Dimensions series has only been around since 2015 but I appreciate the fact you have included it as it can sometimes be very helpful in identifying a set. Thank you.

Based on the Trans-Yellow Plate, Modified 1 x 1 with Tooth Horizontal
which appears only in three sets this is:
71264-1: The LEGO Batman Movie: Play the Complete Movie


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What is the LEGO EV3 rpf file?
I read the LEGO Mindstorms EV3 Communication Developer Kit's document.
I have a question in 4.2.1 (Start program “Demo” on EV3 brick) it is mentioned "The file-extension is "rpf" and NOT "rbf", so how can I generate the rpf file?

rpf stands for "rudolph program file" [source] (I believe "Rudolf" is the internal code name for EV3.)
These are the files created using the "Brick Program" utility on the EV3 brick. Once you have created a program on the brick, you can upload the file using the EV3 desktop software. You can find the files in the BrickProg_Save folder.

However, after explaining all of that, I think the documentation you linked may be a bit misleading. The file extension does not have to be .rpf. The file just has to be an EV3 bytecode file, so a .rbf file could be used too. They probably just chose that example since the Demo.rpf file is installed by default on the EV3.


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Looking for a set based on random pieces with grey marble texture plastic
My son received three, gallon-sized, ziplock bags full of random LEGO's for Christmas. I've been scanning the interwebs for unique pieces in hopes of finding some of the kits and instructions for some of the more interesting (to me) pieces. I've been searching all over and hope to find some direction in this forum. I've attached a picture of some of the pieces which look to be part of a spaceship, maybe. Also, there are some numbers stamped on the inside of a few of them such as AM72433, AM18902, and AM76367. I've searched for these piece numbers as well but I can't seem to track them down.

That isn't actual lego - on the circular piece where you can see the studs, there is no "LEGO" on each stud - they are smooth. What you have is likely one of many knock-off brands.

First, thanks for the quick response! Second, I feel like a dummy. I should have noticed that there are no LEGO stamps on these pieces. I'll try to cull them out and move forward with more promising pieces!

Plus, would you realy think that a lego piece would be shaped like that? (No offense)

X-27's comment is correct, I have 40 years of LEGO collecting under my belt, and I have never seen any bricks with a speckle pattern like that.
You might go through the bricks you got, knock off bricks are very easy to spot once you have seen a few. Cheap looking plastic, dull colors, lack of Lego logos (almost every single part Lego makes is stamped somewhere) are all signs of knock-off brands.
If you want to search for sets based off of real Lego parts, try: https://brickset.com/, they have a part catalog of pretty much every set ever made that you can use to look stuff up.
Here is a random part I pulled up to show you: https://brickset.com/parts/74335/mini-antenna-ass-red-bla

Thank you, both, for the quick response and resource for finding bricks to actual LEGO sets! Have a great holiday weekend!


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How do people build large collections of bricks?
How have people built up such large collections of bricks?
I would like to get into building Lego Great Ball Contraption modules, but this needs a lot of parts to play with. I've got some Lego from (30ish) years ago, but not much seems to have survived, and I've bought a couple of bug Technics sets - but I need a lot more Technics, plus more standard bricks, plates, smooth plates etc.
Buying sets is one way, but expensive and I don't like to just make them and then instantly dismantle again.
Buying on a site like Bricklink is great for specific pieces, or when I have something to get it all in the same colour etc.
I've seen random "1Kg lego parts" on ebay which I can try to use that to build up a load - has anyone tried this?
Or is there another way I'm missing?

I keep my eye on Craigslist and Facebook Martketplace. There’s always someone selling a collection or a bucket of pieces. There’s also a subreddit /r/legomarketplace that sometimes has good deals. I’ve had success with all of these this year and have put together a great supply of parts and sets.

I haven't tried to buy a load but Facebook marketplace seems to have more choice these days for local heavy items for collection. Might be worth a look.

Generally speaking, for bulk bricks the best place is eBay.
For greater selection (probably what you need for largish pieces),

Facebook marketplace

Craigslist

Brick-and-mortar stores like https://bricksandminifigs.com/

For individual pieces, Pick-A-Brick or Bricklink.
Also for several months now, Costco has been selling a 1500-piece Creator box for ~$40 which is as good as I've ever seen for new bricks.

Find a teenager you already know who will spread the word that you will trade old, boring Lego collections for new, shiny video game cash.
Their parents will HATE you.


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Are there LEGO plates without the word "LEGO" on the studs?
I came across this image of the "LEGO Stack Overflow Hat" which is a hat made out of LEGO.

The individual who made the hat asserted, "it's 100% LEGO," but if you look closely at the hat, you'll see there are plates on it which do not have the word LEGO on them.

Since it is ostensibly 100% LEGO, what LEGO plates have studs without the LEGO logo on them?

Also, I can't tell from your tone: Are you asking more towards if the build was truly 100% LEGO, or are you really just curious if there are any LEGO parts that have smooth studs?

I see the word LEGO on the one on the left...

One way to tell it's the image's fault:
The 2x2 plate in the bottom left-hand corner appears to say "LEGO" on 3  out of 4 studs.

There are no LEGO parts with studs that have no logo on them. The hollow versions of studs which are on technic bricks and many other bricks have the Lego logo printed on the insides.
As someone that goes through a lot of used LEGO, I have found that there are some parts that have been worn and the logo is not nearly as visible as it would be brand new. That said, I have never seen any part be worn to wear the logo has been smoothed out. The ABS plastic that TLG uses for normal system parts is quite hard and would really have to take abuse, not just playwear, to get to a point of smoothness on the studs.
In this individual case, if you look closely at any point in the picture, several parts appear to have smooth studs. This appears to be consistent on many of the parts which would certainly not lead the conclusion of wear. Furthermore, even from the relatively grainy photo, the coloration/shine of the smooth studs parts just seems off...
In any case, it's nearly indefinitely false that the hat pictured is 100% made of LEGO parts.
EDIT:
Upon the added pictures from the creator, it would appear I am wrong. While most of what I said still stands true, I underestimated the power of bad lighting! I've seen some photos that distort the look of LEGO, but never to this extent! I stand corrected.

I think a lot of it isn't even the bad lighting, but also the compression. JPG smoothes things out, if you zoom in enough and look at the image you kinda see some darker shades where the logo should be. JPG compression just washes it completely out in the places where its already bad to see.

@SlicksterTheBrickster "There are no LEGO parts with studs that have no logo on them" - is there a confirmation of this fact somewhere on the official LEGO page e.g. on a site with lego.com in the domain? I will probably need this for the court. I'm afraid that an answer of a fan on some LEGO fans' page will not be enough. Currently I'm fighting a person who sold me counterfeits claiming that these were original bricks.

What you are seeing is actually the result of poor lighting, somewhat worn bricks, probably camera app noise reduction, and perhaps image compression, although if you look really closely you can kinda see it's a little darker where the lettering is.
As the creator, I promise that every piece in the hat is 100% genuine LEGO pieces (no knockoff brands). Unfortunately, when I took the picture the sun had set, and all I had was some weaker household lighting.
Here's another shot of the front with the face turned towards the lighting, so the lettering will catch some contrast.

The 2x2 plate in the bottom left does have more-pronounced lettering than the older 2x10 plate next to it, which is why you are able to see it better in the other picture.

To answer the question of are there plates that don't have "LEGO" stamped on the stud, no there are not to my knowledge. Even the very first LEGO plates have the stamp. Some special plates do have hollow studs though.

Wow, I really didn't think the question's image could be so assuringly wrong! I will edit my answer so it does not quite call you out, per se, but most of what I said still upholds.

Looking at the original picture, I'd guess that the real cause is noise reduction software within your camera. In low light most digital cameras make a lot of noise and in-camera processing tries to hide this noise by blending pixels near each other (basically the camera software guesses that if noise filled image contains pixels that are close to each other they should be identical in reality). Most cameras do not have this heavy noise reduction by default but if the owner of the camera has opted for full noise reduction you may get results like this.

Here you can see that the LEGO logo is 'missing' from the studon the bottom-right of the 2x2 tile as well. I think this supports the explanation given by Mikko Rantalainen

I can't see how the middle orange bar is held on. All the others seem to align with one or more studs on the body.

Jumper holding it from behind between the 1st and 2nd stud from the left?

@Angew Yep! The second one up is also held by a jumper on the far right.

There are a (very) few official LEGO elements that don't have the logo stamped on the studs. the new 1x1 dots for example, have a hole through the center, and as a result don't have the logo. In a similar vein, there are a few window frames that had similar indented studs that have no logo.
An overwhelming majority of LEGO parts have the LEGO logo stamped somewhere on the piece though, often in some unobtrusive spot. While there are elements that have no official branding on them at all, they are rare.

I'm fairly sure all the https://www.bricklink.com/v2/catalog/catalogitem.page?P=85861 1x1 round plates with a hole have a very tiny Lego logo imprinted on the underside of the piece.  I've still never seen a Lego logo on a hot dog piece yet, though.


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Can the BrickStore part database be updated?
Is there a way to update BrickStore database with new element numbers, sets, and pictures of the elements? How would you do this?

I found this on Eurobricks from 2014:

I recommend to try BrickStock instead of BrickStore. Brickstore is old and is no longer supported and updated. BrickStock is a fork (using the source of BrickStore) of brickstore.

I use Brickset.com which is very up-to-date and suits the needs of me and my sons.


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Why do LEGO bricks yellow at different rates?

So, here is my LEGO Space Shuttle.  Originally built in 1991, never disassembled (unlike the rest of my sets), so all parts are original and all were exposed to the same amount of sunlight.
However, the amount of yellowing is highly variable.  The hinge for the manipulator arm (just back of the windshield) is like-new white, and the alignment pin for the arm (just in front of the green brick) isn't much different.
Two of the wing panels are much whiter than the others, and although it's hard to see, the hinged parts towards the back are two distinct shades of yellow.
What's the reason for this?

This is a great question. The Transcon 2 shuttle is notorious for its yellowing.

There are several reasons for this:

There isn't just one formula for the ABS plastic that is used in
LEGO. There are actually quite a few. Depending on the color,
translucency, and function, the mix of materials will vary.
Translucent pieces are quite a bit harder and more rigid than other
Lego bricks. Mini-figure accessories tend to be quite a bit softer
than other pieces (so they don't cause internal damage if/when
swallowed).
If you pull out several types of parts and pay close attention to
the hardness, flexibility, and stiffness, you will notice that not
all LEGO is made the same.
Even for similar parts, there is variance in the chemical mixes.
When you get a set, it is highly likely that the parts weren't made
from the same batch of plastic.
Mixing plastics with minor variations can cause changes in the rates
of UV damage and discoloration. It is really hard to get perfectly
matched colors across multiple batches of plastic.
The fact that LEGO colors are so consistent is due to the fact that
they have really high standards for quality control.

Oh, and if you want to restore your set to that new pristine white color, you can treat it with retrobrite or oxyclean and hydrogen peroxide. There are plenty of articles online if you do a quick search for either.

So, what did they do with that hinge to keep it from yellowing, and what disadvantage does it have that keeps them from using it for everything?

+1 for part 2 of your answer - most likely this is btch variation within the parts - different shapes will almost certainly be different batches. Translucent elements are not made from ABS (as it can't be clear) but from a polycarbonate.


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Why are these hinged plates slightly different colors?
Something I've noticed is that certain pieces appear to be slightly different colors for other pieces of the same color. In particular, hinged red pieces seem to be the most noticeably different, especially some versions of the red hinge plate.

As you can see, half of the hinge plate is quite a bit darker than the other half which matches the regular plates. The 1x2 fork clip piece is also a little darker, though not as much as the hinge plate and it's hard to see in the picture. I remember that hinge plate being that way when I got and 3 others in the 10167 Brickmaster Kit (with Digital Designer CD) back in 2004, so I don't believe it was faded or a defect.
So I've long wondered, what's the deal here? Are the hinged plates made of different plastic, like the transparent pieces are?

Quorneng's answer is spot on, even bricks that were from the same set might have been made from differing batches of a particular color and slight variances will produce differing colors. Purple is the most notorious Lego color for having a great deal of variance between bricks, and red is not surprisingly, also inconsistent at times.
To add to the mix, Lego is changing its formulas over time to keep costs down, and to make the bricks more durable and consistent. Earlier ABS bricks where stiffer and more brittle than modern bricks. They have more of a tomato red color, and are easy to spot next to modern bricks.
UV damage can alter the color of bricks over time, although this can be fixed with oxyclean + h202.
Finally, I believe that Lego will internally recycle 'bad' batches of bricks, grinding up and melting down ABS from lots that don't pass QA. This probably also affects brick color. I had a friend who made the pilgrimage to Billund to see the main plant. He told me about how they have a display that shows the casting of bricks to visitors, and it re-uses plastic for the demonstration. I recall that he commented on how the plastic colors were slightly odd looking, presumably because it had been recast so often. This makes sense to me, but it is a second hand story, so don't cite me for your thesis...

The colour of virtually all plastics, like paint, is an 'added' pigment so it is difficult to maintain exactly the same colour.
As others have pointed out some pigments are more susceptible to the effect of sunlight than others - red goes pale - white goes yellow.

But they came out of the box that way, and most pieces really don't vary in color that much.

I bought a bag of 1x4 white bricks directly from LEGO. They're not all the same shade of white. LEGO's colour consistency has declined in recent years from its peak when they bought coloured ABS plastic. Now some colour variation is normal and in some cases it can be quite extreme.


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How to lubricate the 4.5v train motor for set 7722?
How I can lubricate the 4.5v train motor on my #7722 train set? It squeals.

Undo the 2 screws at the top and then take of the top cover.
You can now take the actual motor out  of the casing. It just sits loose in there.
Then you can undo the 2 screws in the bottom to free the metal block with the plastic gears.
It is most likely those gears that cause the squealing because of dust/dirt that got into them.
I would recommend to clean them first using a soft brush. (Paint-brush works well). You can stick an axle through the bushings and turn the gears manually or rotate the big gear shown at the top with your finger. Just let the gears run against the tip of the brush.
Don't stick the brush in too deep! You don't want the hairs of the brush to get caught in the gears!
Then lubricate with a little bit (a few drops is enough) of plastic safe oil. the movement of the gears will spread the oil around eventually when the whole thing has been put back together and is running again. (This might take some minutes of running though. Don't expect the noise to go down after 5 seconds!)
Don't use WD-40. It will degrade the plastic !!!
You should NOT lubricate the actual motor itself. Some of the oil you put on the gears will eventually make it into the electric motor and that should be enough.

Cheers Tonny - perfect answer, and thanks for the disassembled image - my motor's buried away somewhere!

@Zhaph-BenDuguid I had to do some digging too :-) I knew I had 2 of these laying around, but they haven't been used for at least 30 years. Not sure if they still work. At least I was smart enough back then to take the batteries out of the battery units before storing them. Would have been really messy by now if I had left them in.

heh, sadly for a couple of mine either my brother or I weren't that smart - although the mess wasn't too bad - after a little work with some emery paper the contacts were clean and allowing current to flow for my son's orrery ;)

Here's a video of someone lubricating an engine of similar size of the x482 engine inside x469b : https://www.youtube.com/watch?v=L_0SKz8aHRk
I used this technique (if the video disappears: a tiny amount of lubricant directly on the rotating bit of the engine that the axle with gear sticks out of, so between the metal gear that's fixed to the axle and the engine housing) with exactly the same effect as in the video: the high pitched squeaking noise disappears completely, immediately. I probably used the wrong oil, I think it's best to also do this with something that won't damage the plastic, but on the other hand I doubt very much will make it's way out of the engine and the metal parts surrounding it onto the plastic gears or housing.
Note that you can test first if the engine is the noisy bit by holding the power to the contacts at the end of the engine after getting it out like in the picture in Tonny's answer.
Too bad I don't know how to open my 6216m engines to do the same thing there.


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What set are these LEGO assemblies from?

I bought a lot of second hand LEGO  - it was an utter bargain at £10 - and have identified loads of different sets, however this part is infuriating me as I can't identify what it could be part of. Perhaps a submarine? It looks like a periscope in the middle and I'm sure it had at one point 6-8 legs sticking out on the sides.

Set 75013 Umbaran MHC (Mobile Heavy Cannon) , based on the leg shape and the Dark Red 1x1 Headlight Bricks.

Oh my! That is amazing!! Virtual hug coming your way! Thank you so so much!

Howdy Caz, welcome to Bricks.  It'd be good to click the checkbox by the answer to "accept it".  It is even better than a virtual hug.

@Caz See also: https://meta.stackexchange.com/questions/5234/how-does-accepting-an-answer-work

Hope I've accepted it right ?


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Identify lego Set that includes a caravan
I have this set that was given to me, but I cannot locate a caravan like this anywhere.  Is this part of a set or something someone just build?  As you can see there are a lot of missing pieces.  Does it ring a bell to anyone?
Thanks a lot

This is a small build, slightly altered, from set 4997 Transport Ferry from 2008.

The web got tired of me looking for the answer for the past month.  Truly amazing you had the answer.  I appreciate your help.  Thanks again


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Red cargo ship with pier and a tower crane set?
When I was a child (~15-20 years ago) I remember I had a LEGO set composed by a red cargo ship, with a pier and a tower crane that supposedly moved blocks from the pier to the ship.
The name of the ship was Titan, or Atlantic I think.
Can someone find the name of the LEGO set and maybe a picture?

I know of the set that you are speaking of, it was one of the city sets in the late 80s or early 90s. I don't have time to hunt it down myself right now, but you can go look on Brickset, they have a comprehensive catalogue of almost every Lego set that has been released. You should be able to find it pretty easily.

Based on your description, the set is Launch and Load Seaport (6542):

It was released in 1991, and it matches everything you described including a ship called "Atlantic", so this has to be it. If you're looking for some nostalgia, you can pick this up on Bricklink for ~$150.


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How can I mount a Dino head to a wall?
I would like to mount the head of the Dino Triceratops, Item No: 30460, onto a brick/connector so it would be possible to fix it to a wall or over a door entrance. Any ideas on that?

I don't have this particular piece but my advice for most 'non-standard' connections such as these is to use a part that is flexible enough to fit the gap.
The 'Technic, Axle Connector Double Flexible' piece under compression can make a snug enough fit to mount a sharks head.
In this example, you can use two Technic Axle-Pin attached to another two Technic 1X1 bricks.

If you turn the rubber brick 90 degrees on it's side and place two of them together you might be able to attach something that isn't as wide.

very clever. not sure if the dino head connector is wide enough for this exact solution. I have to try. But the idea is inspiring to think out of the box, thanx.

If you turn the rubber brick 90 degrees on it's side and place two of them together you might be able to attach something that isn't as wide.

PROJECT: Dinosaur mount.

Black plaque construction and cradle.

Mounting plaque to a wall.

Reconstructed Ambo100's nice entry, which works beautifully for
Mr. Shark, but the width is too sore for Lady Dinosaur.

The horn piece I have from an old castle set, and you can grab it with minifigure hands. I can't think of a visually appealing way to mount it by the horn,but it is still an option.

visually interesting idea. I think in this case the minifig concept would not fit to the requirement of the project but I will keep it in mind.


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Please identify if these pieces are part of a set, medium grey and red Technic bricks with a window
I have these pieces, constructed a shown, that were given to me in a pile. Is this part of a set or something someone just build?

At first glance it looks like something out of Model Team set, like one of the trailers.
There are two types of standard Technic pins, black friction pins and grey frictionless pins.
Black friction pins are used to build strong connections and grey frictionless pins have low friction and allow parts to spin easily.
It seems odd that the two pins connecting the Technic bricks as shown below use grey frictionless pins as I have never seen an official LEGO set that wouldn't use black friction pins for this case.

The window also stands out as an odd feature in this build.

Looks like something put together for fun rather than an actual set to me ;)

I originally thought it might have come from the Whirl and Wheel Super Truck as well, but that uses the 1x2x3 windows rather than the 1x2x2.

This is a real tough one..
I personally wasn't able to find a set that includes all the pieces in the pictures you included, but I found one that comes pretty close. My guess is that it is a late 80s or early 90s technic set.
What I found which has most of the parts, save for the window element in the middle of your pictures and maybe a couple of the red elements is set 8064-1.
I mainly based my search off the set having at least:
4x red tech brick 1 x 6
2x LG tech brick 1 x 16
2x LG tech brick 1 x 12
and some assorted technic elements like axles and bushings as well as some other red elements.
Hope this aids you in your search!

This is certainly a remainder of a "moc"
With the introduction of Technic in 1977 only the gray friction-less pins existed, so these where used in all Technic constructions by Lego.
Black friction pins are introduced is 1982 (look carefully at the set pictures in the following links: 1981 & 1982). This resulted that from 1982 on the gray pins where only used in parts that needs movement.
So the double gray pin usage in the photo, if original by Lego must be from 1981 or earlier.
The second clue found is the Light Gray 1x16 technic beam. This part is introduced in 8851-1: Excavator, which is a set from 1984.
Conclusion: No official set by Lego

I can't remember a Technic set with a small Lego Classic window, so to me it looks like a creative mind at work.
In early days there were no black friction pins. Studded beams in red and gray remind me of a caterpillar backhoe or bulldozer set from the 1st half of the 1980s. The toothed half width bush also places the parts halfway the 1980s.


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Please identify the set or sets, grey 6 x 6 circle and dark red and white curve with vent
I have these two assemblies which I have no idea if they are from the same set or not. The black square on the round assembly can spin.  Any ideas?
Thanks a lot

The build on the left is from 60002 - Fire Truck - it's the turntable/mount for the ladder:

Based on containing the "Plate 6x6 round", and "Bottom W.Turntable 4x4"
The build on the right is from 60147 - Fishing Boat - it's one of the engines:

It's currently the only set with "Plate W. Bows 2X3½" in New Dark Red.

@pete No worries - I've found the second one too.

The parts on the right are from 60147-1: Fishing Boat

Based on the Dark Red Brick, Modified 2 x 3 x 2/3 Two Studs, Wing End
and the White Wedge 4 x 3 Open with Cutout and 4 Studs

Thanks a lot.  I am missing one.  I will work it out with steering as needed.


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LEGO Modulars Massive Inflation?
What caused retired LEGO Modular sets to spike in value so much?
Any ideas or thoughts would be appreciated.

At certain times of the year (particularly at the start of the new year) LEGO release new sets and at the same time remove older sets from their inventory.
Also, in November and December in the run up to Christmas LEGO investors may take advantage of the increased demand by raising prices. Parents buying presents for their children would perhaps bid higher than usual as they are keen to get the right present and in time for Christmas.

I am talking about how the amount they were sold for in stores or on shop at home, is half or less of how much they sell for. This js year round.

This seems to be fairly normal, these sets are very popular and the same price hike after retirement comes with other themes particularly Star Wars sets. Large sets that are LEGO store exclusives or limited run in particular.

I guess the demand for them isn't too high while in production, but they don't lose demand after retiring driving the price up due to low supply?

The demand for most modular sets are fairly consistent, perhaps more so after retirement. People are also genuinely willing to pay this price,
I was able to sell the first set I invest in (10185 Green Grocer) for 7.5x the RRP which isn't only about half of what the original Cafe Corner can be sold at.

The whole Modular Building idea is brilliant. So far, I could resist because I don't have the space to build a LEGO city. It seems that the MOC culture around the Modular line is still growing. And growth is always a good reason to invest.


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Why won't the loop block in my EV3 program stop?
I am building a robotic hand, and I programmed the finger to close when the touch sensor is pressed, and release when the touch sensor is released. It did that with a loop block -
but when I ran this the finger kept holding down. I could tell because when I tried to gently tug on the motor, it wouldn't budge.
Can anybody tell me what's going on?

Your code instructs the motor to continuously turn in one direction, and because you chose a motor block in the “on” mode, it will continue to turn even during the loop condition check. The loop condition says the loop will continue as long as the button is released (AFAIK, I don’t have an EV3 close by currently to validate this), which means that it does exactly the opposite of what you intended. Change the loop condition to loop as long as the touch sensor is pressed and you will fix this issue. Plus, once the loop finishes, the motor will still continue to turn; you would need to put a Motor block in the “off” mode directly after the loop.

That's what I thought, but I was wrong. The loop goes until the parameter is true. The loop will go until the touch sensor is released.

Even if that’s true, the lack of a “motor off” block immediately after the loop is why the hand keeps gripping.

Also, the "on" block only turns the motor on for the duration of the next blocks run time. If you had the blocks "motor on", "wait 1 sec", and "play sound" in that order, the motor would stop before the sound played.

http://www.legoengineering.com/rookie-ev3-tip-motor-on-mode/

Nevermind, I was wrong

What your current code does is to keep closing the finger until you press the sensor. This code may help.
You might need to change the 180 degrees boxes according to how many degrees the motor has to turn to close the finger.

You need to stop the motor after the loop


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Why are there scratches on new bricks?
When I assembled the new bought "Old Fishing Store, Item No: 21310-1" I noticed a very unusual imperfection of parts. On every one of the 43 tiles "1 x 8, reddish brown, Item No: 4162" I found scratches on both ends. Also the injection points I think are much more visible than normal. I contacted Lego and they sent me 43 new tiles. Great, but still the same mistake. I contacted them again and, Lego service being Lego service, again they sent me 43 new tiles. Great again, but still the same phenomena again. So I ended up with 86 additional bricks that I found not fitting to the Lego quality standards that I'm used to. There was also no explanation or comment from Lego service.
My question is what is causing this strange scratches? The appearance is not consistent. They are not straight and appear in different strength's and lengths.

I'm not sure, but I wouldn't contact lego again for replacements because it seems the mold is creating parts like that.

Looks like something is wrong with one of their machines and it scratches up the surface. What I do find interesting though is that you keep getting scratched tiles even as replacements. While parts are moulded in several different factories (the ones we get in North America are mostly from Mexico), as far as I know, all replacement parts come from Billund, Denmark. So it's really odd that both the original parts and the replacement parts have the scratches. It seems to indicate that you somehow ended up with parts from the same factory made on the same machine.

@Stephen. Actually, I was thinking the opposite, contact them again and see how many times they would send the same stuff or if they start to change the strategy, get into the case and send good bricks or react in another way. This are only some bricks with minor problems but sending the same damaged stuff twice means somewhere the internal process is flawed. I have no use for the tiles, sold the model anyway, but just out of curiosity.

@TheBrickBlogger. Yep, I absolutely agree. I wonder if this also indicates that Lego is becoming  victim of its own success and is starting to lose quality control. There are some videos online where you can see how they supposedly test the bricks in detail when starting a new batch. It is not easy to miss this obvious mistakes.

Oh this is not good! I don't know why there scratches on the Lego tile, but I am sure you can exchange the tiles in the Lego community center!

@CvJBricks Never heard about a Lego community center. where to find? I live in Berlin.

See What causes these 'bite marks' that appear consistently on new bricks?

I have seen this happen with parts originating from older Lego part molds (dies) (like the 16L studded Technic beams in the 42009 Mk2 crane truck). My take is that the molds have been scratched during a maintenance operation but that the mold damage is still within tolerance for Lego.
Creating a new mold (die) is very expensive.

I have sent Lego another mail where I asked not for new damaged tiles, i have no use for them, but for a comment. will keep you posted

they sent me 43 new tiles now the third times but still no answer and of cause still the same mistake. So for now I ended up with 129 additional bricks which I do not want to use. I am considering to do this 10 times more and open up a specialized BrickLink store.

I found the same mistake in the Ship in the bottle.

Since you now have so many spares, you can try polishing one see how difficult it is to remove the cosmetic flaws. Toothpaste will probably work, but I expect you'll end up with a matte finish. If you have access to very fine abrasives (or very fine wet sanding paper), you could also give them a go.


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Lego Boost Variable setting
I'm trying to program steering for a Logo Boost Model. Motor B spins a certain angle and the steering works. To get it running the model - the app - needs to know the current position of the wheels in order to spin the motor correctly. I created several macros where i decide on, and set, a variable. I initialize the model by setting the variable in the main screen of the program interface. But if I go into my steering macros this variable is not known. Instead I can set the variable within. It means, I cannot have a global variable which can be read and set from within macros?
Can anybody clarify or elaborate this?

Looking at this site:
https://legoboost.blogger.de/stories/2709388/
It is in German but I think this picture:

is the important one.
After these settings you have a global value in the white program block.


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Compatibility of maxi sized Mega Bloks
Maxi-size Mega Bloks are larger than Duplo. As far as I can tell they have two times the stud pitch and much larger studs:

What, if any, compatibility is there between the maxi-sized Mega Bloks and either Lego elements or the smaller sizes of Mega Bloks?

Yes, maxi sized mega bloks are compatible with LEGO duplo and LEGO system pieces, but only if the duplo piece is 2x2 studs or larger or the LEGO piece is 4x4 or larger. Also, you can only connect LEGO system pieces and duplo pieces to the undersides of maxi size mega bloks.

The other brands generally fit LEGO bricks. What you have and the Duplo bricks work together. I noticed with any brand that isn't LEGO the pieces are compatible, but they are slightly off like they had a problem perfecting the proportions with the Lego brick. They kind of stick sometimes, and sometimes they are loose enough to just fall off.

Hi Cindy! I have tried to edit your question to make it easier to read, please review it to see if the conveyed intent has remained intact, and edit it yourself if it didn't.

Hey zovits! Thanks! I didn't realize how many typos I had. I appreciate your help!!

There is a Duplo - Maxi Mega Bloks adapter part on Thingiverse, if custom, non-official 3D parts are acceptable.


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Is it possible to determine the approximate age of these bricks only by seeing their injection points?
Is it possible to determine the approximate age of these bricks only by seeing their injection points?

Maybe it is easier to determine the age if we could see the other sides, too.

Are you asking the question to see if it's possible to know the age only from the injection points, or do you just want to know the age of the bricks? Your question is clear, but it's just a kinda strange thing to ask..

Yes, they are from the 1960's from what i can remember

@Slickster. I found a pile of those in an ebay buy of used bricks and was interested in the age.

@Aziraphale. yep, will see if i can post more pictures the next days.

@Slickster. I changed the question based on your comment

I cannot tell by the injection markings but having been a lego collector since 1967 I can tell that they are around that era. They look like some of the original ABS plastic. I also have some even older lego bricks in my collection (circa 1960) and they are of a different plastic but you cannot see the molding points on those.


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Can you identify this LEGO plane set?
Sadly this LEGO plane crashed today. No one was injured, but I do not know where the instructions are, or the LEGO kit/product number. Can someone help me identify which kit it is so I can look up the instructions online?

That's one of the alternate models for Ocean Explorer (31045):

The instructions are available on LEGO.com.


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Bucket Wheel Excavator not powering up?
I just finished to assemble the Bucket Wheel Excavator (42055) set, I inserted new batteries in the battery box and tried to power it up.
The LED on the battery box blinks for a millisecond almost imperceptibly, and nothing happens.
I now wonder what could be the problem, I tried with several different batteries without luck, tried to clean the metal parts, but still nothing.
How can I understand if the problem is the battery box or the motor?

Did the motor function  before you inserted it into the model?  If you didn't try that, you'll need to disassemble the model far enough for you to try it without any possible load.  If you have somehow locked the gearing, then the motor will probably give up to prevent burnout.

No I haven't tried it before. I'll do some test

Even if there are blocked gears, you should be able to hear a small "click" as it takes up the strain.

No I can't hear anything at all

First: check battery condition.
Are all 6 batteries fully charged? Or for non-rechargeable batteries: are they all functioning (new, not expired, no chemical leaking damage)? If one single battery is dead or defective, it can prevent current to pass. If you have another set of fresh (or fully charged) batteries, try using these (but see also the step below).
Second: verify proper battery placement.
The Lego battery box requires the batteries in each sub compartment to be oriented the same way (all tops pointing in the same direction - no battery should have "inverted" orientation). Check that you placed the batteries in the battery box with the right orientation and with the proper polarity (as indicated in the battery box).
As a side note - I always put a piece of plastic sheet ribbon (used in gift wrappings) in each side of the battery box compartment prior to adding batteries; this facilitates subsequent removal of depleted batteries. You can remove the last battery by pulling both ends of the ribbon.
Third: verify that the battery box works properly.
If batteries are healthy and battery polarity is correct, then first test the battery box unattached. The orange slider has 3 positions: on-off-on (either 'on' reverses the polarity for the motors attached). When the slider goes left or right (either 'on' position), the green indicator LED light should remain on.  When the slide goes into the middle position (off), the LED indicator should remain off. If this fails, contact Lego to supply you a spare battery box.
Fourth: verify that the motor works properly.
It is wise to test the battery box and motors prior to assembling any motorized model. If you know the motor previously worked, and you have access to another unused motor, test your battery box with that other motor. If the battery box doesn't manage to operate the motor, try using another battery box if you have one at hand. If that other battery box works, then contact Lego to supply you a spare battery box.
If neither battery box operates the unloaded motor, then contact Lego to supply you a spare motor.

I specified that I tried several different batteries, new and not. 2. my battery box fits only 3 batteries, all 3 oriented the same way. 3. The LED doesn't stay on... I guess it is

@FezVrasta there should be 6 batteries in total, 3 in either compartment of the battery box. If the green LDE indicator light never stays green, even with all batteries in, then your battery box looks indeed defective.

oh f**k, I didn't realize I had to put other batteries the other side! It works! Damn I'm such an idiot ahahah

As Phil B suggests you really must start by testing a motor by itself from the battery box. This will confirm whether that battery box is working or not.
My experience in Radio Control has taught me to test each "electrical" bit one at a time and in a logical sequence starting from the power source until the fault is identified.
For the future it worth testing electrical things like the motor and battery box before they get "built in" to a complex model.

Thanks for the advice, there's nothing between the battery box and the motor, they are linked directly and the battery box turns on manually, no radio controls. What I wonder is if it is normal for the battery box led to not stay on while the battery box is powered?

When no motors connected to it, the led should stay on. The led can go out if faulty or too many motors are attached...

Do you have another battery box from another set you could try?
You could purchase the motorization set to have a spare battery box and some other useful components.
However, I think I own at least 50 battery boxes, I have never experienced any issue with them.
Likewise, I never have experienced any issue with motors that are new.
What also could be the issue is that you have made a mistake in a building step somewhere which causes the drivetrain to block.
The motors and battery box have circuitry in them so they shut themselves off if too much current is drawn, which happens when motors are blocked.
I would test this with all switches in neutral and then see if the motor spins freely.
If this is the case you'll have to test every function, see what blocks where and resolve it with the aid of the building instructions.

I already tried to run it with all the functions set to neutral. I can't hear any sound at all from any part of the set...

Take the battery box out, and one motor. Connect those, hold the motor in one hand, and see if it works when you turn on the battery box. If yes, the problem is in your build as per this answer. If no, there’s either something wrong with the battery box, the motor, or the way you inserted the batteries (or the batteries themselves, but since you’ve tried several this is unlikely).

If you can demonstrate issue with a motor or the battery box, lego support will be happy to send you replacement parts...

I don't think there's anything wrong with the construction, as last resort test I tried to manually rotate the gears connected to the motor and they rotate just fine (obviously with a bit of difficulty because of the motor not being turned on)


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Is it worth to start with Dimensions now?
From what I know Lego will cancel the Dimensions game soon. Right now it is possible to find on ebay very cheap starter kits. Is it still possible to play the game after Lego is closing down all activities or is a Lego server essential for the game functionalities?

I don't own the game myself, but it's not an online game, so once you have it installed and set up you should be able to access all of the gameplay and content

The Lego Dimensions game is actually a console game available on the PlayStation 4, Xbox One, Xbox 360, Wii U, PlayStation 3. So as Shea stated, once you have the game, you can play it whenever you want. All you have to do is insert the disc into your console and load up the game.
About your concern of buying the starter kits, getting the one on eBay could be a choice, as long as you trust the seller. Another way is to get it at Target or Walmart before they don't sell it anymore. Another suggestion for you is to get all the current available sets for Lego Dimensions that are available in store, as once they are no longer being sold at stores, the value will skyrocket. After you have gotten the desired in store sets would you then get it off eBay.


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Help in identifying elements used on LEGO Batman movie's Daleks
I've been working on making a replica of the Dalek from LEGO Batman.
I've worked my way through this video tutorial and the author identifies some differences between their (awesome) effort and the original from the film.
I've built a replica in the LDD and was trying to identify how the laser was constructed.
Currently the author is using a 64567 "Light sword shaft" and 30374 Light sword blade, something like this...

This is okay, but lacks some of the articulation which it should be capable of.  Now, I appreciate that the movie was CG based and some "cheating" probably took place, but I'd like to get as close as I can
From the movie...

I've identified that the business end of the barrel is (indeed) a 64567 "Light sword shaft", but I can't identify the shaft element which it is attached to (highlighted).
The 64567 part needs to attached to a 3.2 shaft part, but I can't identify the part which seems to have been used, any help would be greatly appreciated.
I've spend some time going through the LDD catalog and brickset trying to identify it, without luck.
It "could" be 32828: Plate 1x1 Round W/ Horizontal 3.2 Shaft, but it doesn't seem to have the same reduction or node at the end. I've tried using a 92690 "0.2 Shaft w/ cored knob" along with a 87994 "Shaft 3M 3.2" to join the 64567 together, but it doesn't generate the same shape (and is generally to long)

It looks like Minifig, Utensil Tool Box Wrench - 3-Rib Handle
Item No: 11402i (although it looks like the ribbing may have been omitted in the CGI model):

The socket end can clutch a stud, so it can be attached there.
This newer variant of this piece has come in flat silver, which is probably the closest color so far if not the color, in 5 different sets so far.

Wouldn't you know it, it's not in the LDD catalog . I'll need to some rework to flip the studs, but otherwise I think you're onto a winnder


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How do you make a triggered counted ball drop?
Is there any solution on making a drop of a counted number of balls when one ball passes through the system?
For example: One ball falls into a hole on the top and ten balls (plus/minus (not important) the ball that fell in) come out.
I have thought about letting one ball drop into the system and activating a lever which pushes open a tunnel with a lot of balls in it and the lever then self-closing afterwards. To limit the number of balls dropped there should be a closing mechanism on the upper side of said tunnel that closes when the tunnel itself opens, so only the balls in that section would get dropped...
But how would you do that without jamming?
If someone cares about the ball-size and weight, that should not really matter because the basic construction can always be a little bit reconfigured if the ball size is between 12 and 15 mm. Same for the weight.
EDIT: There has been some misunderstanding apparently, I am sorry for that. It should be noted that this mechanism should be repeatable for as long as you have a supply of balls coming in from a second source (auto-refilling of the reservoir). While this itself is not an issue because you can simply make a big pressure-based ball reservoir that gets triggered everytime the small reservoir empties, it is an important aspect because it means the whole mechanism should not only be able to run one time.

I've seen this done in a GBC module that counts the balls that pass by. It worked with scales that eventually tipped over, each scale representing a decimal of the total number of balls that passed by.
Can't exactly find the GBC module but found this clock from jkbrickworks that uses the same principle.

This solution seems like the best because it's probably the most simple and reliable way of solving a problem.

This is not a bad solution, but it has one issue: Since it is designed for the reverse purpose it does not refill. After you dropped the ball in and got 11 balls out, the next ball that goes in stays in there instead of 11 balls going out again.

I don't know if this is practical, and I can't test it as I don't have enough compatible balls to build GBC type mechanisms, but what comes to mind is:

Have the balls run down a trough.
The trough ends in a segment of trough which is 10 balls long and pivoted about the long axis.
The triggering ball causes the trough to spin about that axis, dumping the balls sideways into a receptacle.
The top end of the moving trough is designed so that it is flat and blocks further balls from sliding down (without jamming) until it returns. This is the critical area to prevent it from jamming.

For ease of operation, the trough's weight should be balanced about the axis. The weight of the balls should assist in the dumping movement — either not enough to start it, or the trigger mechanism prevents movement until triggered.

Very interesting idea. I will try it and report back


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What's the fastest way to rebuild different sets that have been brought together
My mom did something to my LEGO. When I was a kid I loved playing with them. Frankly I have no interest in it anymore.  She broke down all them sets, and put them all in a huge box.
I still can figure out some parts, but I don't know if it's better to break down every piece and rebuild from scratch.  I'm not talking about 3 or 4 sets, more like 20 to 30 LEGO sets worth around 3k to 4k euro...  I want to resell it, sadly she took away the building books and the boxes and did them away too.

Some people in this forum are very good at identifying sets. Add some photos of your LEGO and I am sure that at least some set numbers will be found. Then you can use a part list, e.g. on Bricklink, to collect the pieces of the sets.

Could you clarify if you need to identify some of the sets, or if you want some help to separate the piece of each set, because manual instructions should have at the end a list of all the pieces.

I can identify them myself, just looking for the best and fastest way to rebuild them. I already seperated pieces by color. Right now I rebuilded the smallest thing I had because it was near completion anyway. Anyhow I see I miss a few things though, bobba fett's helmet for example. I was wondering if there is some place where I can buy these spare parts too

Related: https://bricks.stackexchange.com/questions/1160/how-should-i-go-about-selling-a-large-number-of-unsorted-lego-sets

So you have all parts and instructions in front of you and your question now is how to assemble the pieces as fast as possible?? Without interest in LEGO, as you mentioned, I would use Bricklink to collect the pieces of each set, put them in bags, take product photos and sell them separately on Ebay.

In order to gain value out of this, you're going to have to put some work in.
Start with the largest sized kit that you remember doing and assemble the parts (find the building instructions online).  Then move onto the next smallest, and so on.
Obviously, you're not going to remember the details of all the kits you had, but the largest ones should be more memorable (and usually they're worth more).

I like this plan, but I actually think it would be easier to start with the smaller sets and build-up to the larger sets.

Easier, yes.  But if in doing so, you take parts away from the larger sets, you're implicitly losing money on resale (which is what the OP is attempting to do).  I'm just recommending a way of getting the maximum value out of that box of bits.

That makes sense too.  I figured he'd be buying missing parts on bricklink anyway.

Without the instructions it's going to be hard to reconstruct the sets and it will reduce the price anyway (I think people who cares for old sets also want the instructions). But you can find many instructions online.
Your valuation of 100-200€/set is probably unrealistic. There are lots of sets in that price range, but they are fairly large (especially in the upper end), so it doesn't sound like a typical kid collection, and when you include that it's used without boxes or instructions it becomes even more unrealistic.
I would need to see the parts to give a real recommendation, if it's all (but it has to be quite close) bigger parts that are reasonably easy to connect I would try that, but you easily end up spending more time looking at the model to find out where some small piece goes.

Hello, thank you for your answer. I have begun rebuilding a bit of small sets. Reason why I try to look at the price is because these sets already cost that much in the store. I have a huge collection of lego star wars, with a lot of big sets.


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How often does LEGO make colour substitutions?
I'm currently building the UCS Millennium Falcon and ran into a step where the instructions say to use two different shades of grey in the greebling, but the bags for that step only contain one single shade (but the right quantity).
This seems odd for such a prestige level release, so my question is whether this is "normal" or whether I should be asking for replacement parts.
To clarify - step 12, the round vents at the top back of the Falcon should contain black 1x2 grills, and dark gray 1x2 grills are used elsewhere on the paneling for detail.  The bags for this step contained no black grills - just the dark gray. Proper quantity, just wrong colour.
This isn't a case of the constructor misusing one part accidentally in place of another - the step is built with no missing parts, only a few random spares, it just has the wrong colour grills in the vents.

Which step are your referring to?

Like asked above, which step are you referring to? Those who have built the set already should be able to help you identify where the problem is.

@chicks apologies for late response - step 12, where the round vents in the rear of the Falcon should contain black grills, and the greebling elsewhere on the panels uses dark gray grills, but all the grills included in the steps bags are of the dark gray colour.  I have checked this against online reviews and builds, and it should definitely be black grills.  This isn't a case of "oops, used the wrong part elsewhere", hence why the existing answers are completely off the mark.

In my experience, this typically means you used the other colored part by accident somewhere else in the model, for example in a place where it is used on its own, and it was difficult to determine the exact color of the piece at that time. This happens a lot with colors like dark bluish gray, light bluish gray and pearl gray. You will need to go back through the manual to find previous places where this piece was used and confirm you used the right color.

Totally agree. I have built hundreds of sets and I can say that I have never found an error in the instructions or part counts even once. Not to say they don't exist, but the chance of builder error is just so much greater!

Thanks for the answer, but I'm talking about a large quantity - 30 to 60 pieces in a single step, not a single piece here or there.

It might help to compare what you have with photos online of the same portion of the model.
In my experience, I sometimes find the right part in a later bag, or left over from a previous bag.
While I was building my USC Falcon, I just maintained a pot of "extras" and dipped into them whenever I couldn't find a particular part.
There's an awful lot of small parts in this model, and it's easy to skip or add too much greebling.

All the parts are in the right place, just the wrong colour.


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Why can't I install the NXT software on macOS High Sierra?
I just got an Mindstorms EV3 for Christmas, and learned that you can have the NXT communicate with the EV3 in the NXT software. I tried to install the NXT software on my Mac, but all that happens is a gray box pops up and stays there. I have macOS 10.13.2 High Sierra, and I'm wondering if that might be the problem because they don't update the NXT software anymore. Is there anything I can do to fix it?

Possible duplicate of What software should I install for NXT on OSX El 10.11.2 Capitan?, as the exact MacOS version doesn’t really matter here.

I'm not aware of any feature like this. Perhaps you heard that the NXT can be programmed using the EV3 software?

NXT software can't know anything about the EV3. The EV3 software can program the NXT.


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Where is this piece in LDD?
I'm looking for a certain piece for building my set in LDD. I've already looked through the extend theme, but I can't find it. If anyone knows where to find it, it would be super cool.

I assume you are talking about Lego Digital Designer since you mention "extend theme". Also assuming the design ID is correct (6163991) according to your screenshot and also the brickset database, searching for it in LDD in the search bar with updated bricks database and indeed in extended mode does not produce any results. I think it safe to conclude that the element is not present in the LDD bricks database. This happens, perhaps this will be corrected in a following database update but those only happen very sporadically anymore. Could be that the design ID is incorrect, which could be figured out by using the "Replace parts" service of lego, but this service isn't available this time of the year.

That's a rather new piece (from 2017), so it's really not surprising that it's not in LDD.

This piece is available in the 4.3.11th version of LDD in 10th set category