text:
How to open first version of the pneumatic cylinder? (Part no 4688c01)
I have a Lego Technic set 8040 from 1984 with the first version of the pneumatic cylinder. Unfortunately, the shaft on the cylinder broke.
Apparently the top of the cylinder (lid) is glued. Is there a way to soften the glue (maybe with warm water) and open it? Or is my best option cutting it open and than gluing it again?

I have no experience with this specific piece, but I'd guess warm water shouldn't affect the glue. If it were to do so, then the glue could easily be softened by nothing more than direct sunlight, which LEGO would clearly want to avoid.

Thanks everyone for the answers. It gave me the courage to take the piece to the cutting block... And guess what? I now have an almost functional piece. It's not extending 100% and sometimes I need to give a little push. But at least my son can play until I get a replacement on BL.
Here is what I did:

Cut the top off with a sharp blade (yes, it isn't kind).

Inside is a rubber gasket and a plastic piece underneath it. The tip of the plastic shaft, which holds the plastic piece, was broken.

Using a piece of PVC pipe, I made a small extension and glued it to the tip of the shaft. I used superglue and baking powder for that. Here is where things could have gone better. The extension was not very well aligned with the shaft. So the plastic support became a bit off-center. Had it been better aligned, I believe the fixed piston would work better.

I placed the rubber gasket and plastic support on the shaft and used hot glue to secure the piece in place. I then put a little Vaseline inside the cylinder and closed everything with hot glue. I decided to use hot glue in case I ever needed to open the cylinder again.

It's not pretty. But it works - sorts off

Nice photographs! Please note: It is perfectly acceptable on this site to accept your own answer after a few days as "the solution".  Accepting any answer (by clicking on the checkmark to the left of the answer) will mark the question as solved make it available to cross-link it with (future) duplicate questions. And you can change your mind later and make another answer the "accepted answer" if necessary.

The original glue was solvent based. This means that both sides of the joint are more or less fused/welded together. It is not a simple case of "2 pieces with glue in between".
Any solvent that dissolves the glue will also eat the plastic itself.
I think your best bet would be to use a very sharp scalpel or thin-bladed hobby knife to carefully score along the grove around the top until you have cut through.
That should give you a nice clear cut and (after gluing it back together) should be almost invisible.
I can't give you any good advice on what glue is best to use.
I've used acetone myself a couple of times, but found it dissolving the plastic too aggressively, which makes a precision glue-job next to impossible.
(It might be ok if used in very, very small amounts.)
Polystyrene glue (used for those plastic model-kits) will work on Lego, but doesn't have much strength. I doubt it would hold the cap in place when air-pressure is applied.

It might be hard or impossible to fix this so I'd rather address how to fix the issue of having non-functional element instead. You can look into acquiring a used version of the same LEGO item from Bricklink. It might be just cheaper, quicker and easier to do.


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Can you help identify these bionicles?
My elderly father lied to me. He told me I was his favorite child. Later in life he is now asking me to identify his metric ton of Bionicles pieces. He isn’t in the best health so he can’t do it himself, and I’m not the smart one. So I am here with hopes you can help give me some direction so that I can assemble these guys for him.
I don’t know if they’re complete, so I can’t help him sell them until I solve these puzzles.
Thanks in advance.
https://photos.app.goo.gl/1CPqxMZn27NNqny56

And help me learn how to post all of the photos I took for this post.  Post editing tells me my iPhone photo is too large.

iPhone photos will be multiple-megapixels with high color information. The maximum photo size for StackExchange is 2MB. You can edit your photos on your phone or a PC and shrink them to 20-25% of the original size and then save as a low-quality JPG, those should upload fine. Edit: looks like you can upload directly using the StackExchange mobile app source

I editted the post to add a link to the photos!  Thanks!

I've had a look at the linked photographs and... wow, that's a lot of stuff.
If you plan on reconstructing the sets, remember that you can search for instructions given a set number.

From he above picture I can identify:

7156-1 "Corroder" (which is not bionicle but rather Hero Factory) (searched for lime bionicle legs)
8696-1 "Bitil" (searched for yellow bionicle legs with 3 technic holes)
8695-1 "Gorast" (just by combing through list of bionicle sets)

8622-1 "Nidhiki" (dark green 7+3 liftarm)

8727-1 "Inika Toa Jaller
" (pearl gold bionicle chest)

8983-1 "Vorox
" (tan bionicle leg)

Bits of 8533-1 "Gali" (medium blue bionicle parts)
A Mega Blocks blue&white robot at the bottom right, most probably the "ice" "transformer blok bot" from this other question. Note the "mega blocks" markings in the center of groups of four studs.
Yellow parts possible part of aforementioned 8696-1 "Bitil"
Lots of unknown parts

Green technic connector with two ball sockets, from one of four possible sets. I'm guessing 8914-1 "Toa Mahri Hahli
" based on the attached dark blue parts, and a mask from a different photograph.
Clawed feet from aforementioned 8983-1 "Vorox
", even though the colour doesn't seem to match in the photograph (due to white balance, perhaps?)

8979-1 "Malum" (red & "marbled bright orange" chest, bottom center)
8567-1 "Lewa Nuva" (lime legs, bottom left)
8570-1 "Gali Nuva" (medium blue legs, between top right and middle right)
8591-1 "Vorak" (spikes on black bionicle back cover with groove, just above center)
8589-1 "Lerahk" (green back cover with groove; note spikes through groove are switched)
8590-1 "Guurahk" (blue back cover with groove; note spikes through groove back are switched)
8592-1 "Turahk" (back blades with holes, inserted in the blue back cover)
Lots of other unidentified parts

8568-1 "Potahu Nuva" (tan legs connected to brown parts, above revolver)
8911-1 "Toa Mahi Jaller" (6-shot revolver-like part, connected to red&orange parts; also mask appears in later photograph)
Transparent wings with hexagon-like pattern from aforementioned 8695-1 "Gorast" (in the pile at the very top)
Lots of other unidentified parts

8561-1 "Nuhvok" (via trans-neon-green teeth)

8615-1 "Vahki Bordakh" (disk launcher with trans-orange head connector)

8685-1 "Phantoka" (black & grey projectile launcher paired with a mask from a later photograph)
8913-1 "Toa Mahri Nuparu" (revolver projectile launcher and mask from later photograph)
8925-1 "Barraki Deepsea Patrol" (6x11 assembly at top, with 6x10 + 1x6 black plates, consistent with black whip from later photograph)
Aforementioned 8914-1 "Toa Mahri Hahli
" (remaining revolver projectile launcher)
Other unidentified parts

8747-1 "Visorak Suukorak"
The black head appears in two sets. I'm gonna take a wild guess and say 8919-1 "Mantax"
8743-1 "Visorak Boggarak"

That's all I can identify for now. You might want to rebuild all known sets, and come back here later with the remaining parts for a second round.

Wow!  Thank you SO much. This is incredibly helpful!

The blue and white Mega Bloks parts are from this set

@Syberion I'll edit the answer to add that info, thanks!

source: Stack Exchange

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

sort: votes


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How do I disassemble Powered Up Motor XL?
My question is, how do you take the XL motor apart?
I tried with my knife and hands, but unfortunately, it is still whole in one piece (tabs).
I got the XL motor from the set 42099 and I would to make the set again if it wasn't stuck.
I want to open the motor so I can see what's wrong with it; I think it is actually a broken motor.

What does the motor do or not do that makes you think that it is broken?

Also see https://bricks.stackexchange.com/q/15031/3498

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


text:
Does anyone know what set this is from? Possibly Star Wars, lots of greys
From a friend, we have what looks like a Star Wars set of 9 bags. Bag one is missing, but I think it was just built as this. The bags say 2011 and 135149. Thanks!

It looks like 75093-1 Death Star Final Duel
Based on:

Light Bluish Gray Technic, Liftarm, Modified Bent Thick L-Shape 2 x 4
Dark Bluish Gray Slope, Curved 2 x 2 x 2/3
Light Bluish Gray Plate, Modified 1 x 4 with 2 Studs without Groove

That Trans-Light Blue Plate, Round 1 x 1 is in the inventory, as is the Light Bluish Gray Technic, Axle 1L with Tow Ball, and the Light Bluish Gray Brick, Round 1 x 1 Open Stud, and the hinges, and the White Brick, Modified 1 x 2 with Pin, but not that blue-like cheese slope in the top right...

... or is that just a weird reflection on a Dark Bley piece?

Omg, that is it. Thank you so much!

@RSchulz : looks like a reflection to me. The shadows indicate a light source that is just about the right angle to reflect off that cheese slope into the camera.

@SanderDeDycker I'm so glad I didn't spend time hunting for that piece as a Light Blue or Sand Blue or Medium Azure or whatever color it seems to be...

It's called bluish grey for a reason I guess :)


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Where can I get replacement battery connectors for old Lego Duplo Train?
I have the same Duplo Train that Pieterjan posted a picture and video of in September ('Old Lego duplo train not working on batteries'). In my case, it is clear that the battery connectors are corroded due to leaked batteries, and some have snapped as I removed them to clean them. Any idea where I might be able to buy replacements?

Considering that the contacts seem to be made specifically for this model of Duplo Train, I think an exact fitting off-the-shelf version likely doesn't exist. You could buy sheet metal of the same material and thickness, then try to cut and bend it to the right shape - or buy another (possibly otherwise broken) Duplo Train of the same type (or in red) to scavenge the connectors in used but official condition.


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Not sure what this is - bag 2, whites, purples, light blues
I got this at the thrift store and have no instructions. Does anyone know what it is?

41332-1 Emma's Art Stand
Based on

White Plate, Modified 2 x 2 x 2/3 with 2 Studs on Side
Medium Lavender Plate, Round Corner 2 x 6 Double
White Plate 2 x 2 Corner

That yields 3 sets, only 1 of which is a Friends set, and it's one that has that mini-doll in it.

...but that set doesn't cover all the parts seen. The 8x8 tan plate, 1x3x1 and 1x2x3 white slopes, and other parts from the bag at the top of the photograph are probably from different set(s).

Yup; trying to ID a set from an unclear photo of a loose collection of parts in an open bag seems like a fool's errand. I concentrated on the do-able task of identifying the sealed bag.

I wouldn't bet money on that being an 8x8 plate in tan - I can not be at all certain just how big it really is.


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How to find out where a previously lost brick fits?
Rebrickable manages a list of lost parts. If I later find one of these, I have to go through the PDF of instructions to put it back where it belongs, which can be tedious. Does someone know if there is a database of searchable instructions to directly get to the right page? Or better yet: instructions for commercial sets in a format similar to the one used by Bricklink Stud.io?


text:
I want to recreate a few things I saw but I don't know what pieces I need. Can you identify these bricks?
I want to recreate a few things I saw but I don't know what pieces I need. Can you identify these bricks so I can buy them on Bricklink?

Most of the bricks seen there are fairly common - plates, tiles, round bricks (2x2, 1x1 and cone 1x1).
Among the "uncommon" parts I can tell:

Technic thick liftarm, 2-long in blue.
Round 1x1 plate with swirl, in silver.
1x2 plate with perpendicular technic pin on top, in white.
I can't tell exactly how the 6-stud-long round parts of the scroll are done, but I suspect some clever SNOT plus something like 1x2x1 curved slope in white.
Barb/Claw/Horn/Tooth (small) in either silver or pearl grey.
Bar 4L in reddish brown.

The SNOT in the scroll is particularly tricky - the correct alignment between a curved slope and the 2x2 round bricks cannot be achieved with the usual parts used for SNOT, as far as I can tell (bricks with stud on side, etc).
For that SNOT assembly, I'll suggest using 1x1 plate with bar handle on long stem  together with 1x1 plate with horizontal clip plus a few plates, like so:

As for the stickers, they seem custom-made.

What's SNOT? I've not heard that one before.

See https://bricks.stackexchange.com/questions/61/what-is-snot-building

I got some Technic thick liftarm, 2-long in blue and Round 1x1 plate with swirl, in silver and some Bar 4L in reddish brown. I tried putting it all together and the bars are too small to hold it all together...they  fall out of the Round plates and liftarms.

Unfortunately I cannot know how it is held internally. Maybe they're held by non-lego means, such as plasticine or clay.

Bars inserted through technic pins?


text:
Plate perpendicular to bottom of 2x2 round: is this connection legal?
I've played enough with 2x2 round plates and 1-stud-wide plates to know that it's possible to attach a plate underneath a 2x2 plate and perpendicular to it, like so:

The same connection is possible using 2x2 round bricks instead, or using 1-stud-wide tiles.
An observation: each of the 4 wall sections of a 2x2 round brick/plate can flex slightly. This does not happen with the continuous walls in a square brick/plate.
So:

Is this connection "legal"? (i.e.: Does this connection stress the parts involved?)

Has this type of connection been used in any official sets?

A word of warning: Do not attempt this technique on part 6143 "2x2 round brick reinforced": it won't work, and you risk denting your plates (as I just did). Do look for a flat wall section at the bottom of the round plate/brick.

Nice find! I have yet never seen this connection style, neither in an official model nor in a collection of illegal techniques - but my lack of experience doesn't mean anything conclusive.

TBH I "discovered" this during the 90s (with the supports from 6930-1); but it was only yesterday, while trying to reverse-engineer the SNOT technique used in this other question, when I realized I haven't seen this technique documented anywhere.

Does the receiving plate/brick have to be round? Seems to me that a plate fits between any center tube and the element wall...

The fit between a plate and a pre-2004 brick is way too tight IIRC - tiles can easily get stuck inside and require pincers to get removed - so I suspect that would stress the wall of the brick. Post-2004 bricks have thinned walls (to save on plastic, AFAIK) so the wall-tube gap is larger than the thickness of a plate/tile. In other words: the connection is loose. Also, an observation: the "wall" in a round 2x2 plate/brick can slightly bend "outwards" without being supported by other walls; this intuitively tells me that the connection is flexible.

Thx for the clarification, however "to save on plastic" is in my opinion not the reason walls were thinned... The thinning was done to have a more uniform thickness of injected ABS in the mold. Non-uniform thickness causes warping because different parts of the element cool down at different rates...

I was hoping to see a question here on bricks stackexchange about the thinning of walls, but I can only find information about the great bley schism. :-/

It's an illegal brick technique due to you breaking the bricks and it makes the bricks wear away faster and the technique was never in offical Lego sets.

Do you have any sources (studies, expert opinion, experiments, etc.) for these statements? I know the last one ("The technique was never in official Lego sets") is not possible to prove, but the "it makes the bricks wear away faster" should be citable.

I think my question is clear enough about damaging the bricks - using part 6143 will dent plates (and is therefore clearly illegal), but I'm asking about part 3941 et al, as pictured.

When I asked a similar question in an FB group, in a MOC where I wedged one plate by its edge, on another at its edge at a right angle to each other, I was told an unusual move that doesn't damage pieces is called 'unorthodox'.


text:
Plate perpendicular to bottom of square brick/plate: is this connection legal?
This is closely related to the question about jamming plates underneath 2x2 round bricks, (and indeed prompted by a comment there), with differences explained later.
It is possible to attach a plate (or tile) to the underside of a square rectangular brick/plate/tile, between the wall and the tubes, like so:

Note how the distance between a brick's wall and its inner tube seems to be the same as the thickness of a plate:

A few observations:

This connection feels looser (seems to have less clutch) than using a round brick.

For 1-stud-wide plates, this connection doesn't guarantee a straight angle. The edge of the plate sits loose inside the brick.

For post-2005 regular bricks (i.e. non-sloped), since they have thinned walls with notches at every stud, the connection is particularly flimsy. A 1-stud-wide plate just won't get any grip at all.

The walls of rectangular bricks are connected to each other, so bending a wall "outwards" (to jam a plate/tile inside) means bending or stressing the perpendicular walls (as far as I understand the physics of solid materials).

So:

Is this connection "legal"? (i.e.: Does this connection stress the parts involved?)

Has this type of connection been used in any official sets?

I'm guessing the "thinned walls" comment is the key indication that Lego doesn't consider it legal - otherwise they'd have had to preserve the old style of wall.

Would this connection be considered "in system"? it seems the parts are offset by half a plate in two dimensions, and half a stud in the other, which would be in system.

Indeed - the offset is 4 LDUs (half a plate) in two axes. The plate, however, can slide along the third axis. This becomes obvious when using a 2x8 brick: a plate/tile can slide between the wall and the tubes.

To answer your second question: The technique was used by Lego in 1976's set 726 (12v Western train with 2 Wagons and Cowboys), to attach the horse's tail.
See page 13 of the instructions:

Amazing! And look at the old legs used for the horse, too!

I'm not quite sure this is still legal, keeping in mind 46 years have passed since quoted use in 726 set. There are cases where TLG used certain building techniques, but then marked them as "illegal".

@Alex: That's why I didn't venture an opinion on the 'is this [currently] "legal"?' part of the question.

Great find! I remembered this technique from when I was a kid, but didn't know if it was in a set, or discovered by me. I could only find 'plate between studs' connections.

Some anecdotal evidence against legality: I have built such connections with rather old plates a long time ago and one of the outer plates failed (the wall breaking off). So it certainly puts the plates under some stress.


text:
Any tips for putting figure's hands into the arms?
I've recently bought some Chinese LEGO-like sets and, even though the quality might not be the same as the original, I sometimes think it's a reasonable tradeoff for the 50-75% price discount. Specially if you consider I won't really play with them; they don't need to  resist 37.000 times being assembled.
One thing that really annoys me, though, is that they always send the figures without arms and hands attached, specially the hands, which are horrible to put in the arms. They are really tight, require a lot of pressure and hurt my fingertips. In the photo below, those 2 Chinese figures are from different sets. I struggled to fit the one with white hands, but no matter how hard I press the black hands of the other dude, I can't fit them in.

I tried so hard on the next fellow that I broke his hand, leaving it stuck in his arm:

Are there any tips for placing those hands? Either avoiding so much force or improving the grip?

The issue you are experiencing is the result of clone minifigures not going through 37000 assembly cycle you've mentioned. You get what you've paid for. And the answer is pretty simple - buy LEGO minifigures if you need desired quality.

As the minifigure is covered by patents, the manufacturer of those sets are violating the law and buying them you're supporting that.

I’m voting to close this question because patent right infringement goes against the LEGO Group's Fair Play requirement.

Patent right infringement, where? Violating which law of which country?

Trademark protection exists at least in the EU: https://www.bbc.com/news/world-europe-33147827

@zovits don't worry, neither myself nor the seller live in the EU.

@maraja If you tell us your actual jurisdiction, we can probably find the relevant protection agreements.

if the fit is too tight you could use a fine grit sand paper to very slightly reduce the thickness of the shafts.

Try putting something in the minifigure hands that would give you a bigger grip or more leverage for insertion into the arms. Something like bar 4l gives you a much bigger surface and with balanced pressure on both ends of the bar, you should be able to insert pretty well.
Note that almost anything that can be inserted into a hand would work.

Thanks, I have a spear somewhere and will try!


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42131 Bulldozer Testing
Got to the testing page and everything is working correctly except the left track is going in the opposite direction to the app animation.
Should I start again?

Thanks - I saw that and have also now rebuilt and the same parts are still moving opposite to the animation so I will continue to build it as they have done - hoping for the best!!! Otherwise, it’s a massive tear down and rebuild!


text:
How to change colour of the bluetooth/charging RGB LED in the hub?
I have the Mindstorms set 51515 - Robot Inventor. I want to display the progress of a robot's work using the LEDs.
How can I change the colour of the RGB LED that the hub uses to indicate the Bluetooth/charging status?

Short answer: You can't.
Longer answer: It should be possible to do with custom firmware, but it's (a) not worth it, (b) difficult from a technical standpoint, and (c) a bad idea.
Disclaimer: besides being an AFOL, I have some experience in the microelectronics industry.
What's this "firmware" thing, anyway?
When you load a program into a spike/mindstorms/ev3/etc hub, the hub is not running just your program. It's running a lot of stuff under the hood.
In fact, your program (i.e. "the user program") does not communicate with the hardware (motors/sensors) directly. It communicates to the operating system of the hub. That's commonly called "firmware" since it lays somewhere in between "hardware" and "software". It's assumed to be immutable and reliable as hardware, but with some effort can be changed/updated as software.
The firmware handles the tricky bits of computing that you don't want to care about - such as the Pulse-Width Modulation for the LED colours, the Real-Time Clock to run commands for specific amounts of time, or the USB and BLE network stacks to communicate with desktop/laptop computers.
Note that your user programs do not have full control over the hardware, or over all the features of the OS. For example: any device with a USB stack and a button can be (in theory) converted into a USB mouse (technically a "USB HID")
Why is it not worth it?
Because it takes a lot of time; and given the amount of person-hours that it would take to develop custom firmware (such a pybricks, the only non-lego™ firmware I'm aware of), you'd be way better off getting an Arduino and/or a Raspberry Pi. That way you can learn to take full(er) control of your hardware.
Or, if you just need extra lights, get set 88005-1.
I'm assuming you are reading this from the point of view of a person just learning computing/robotics. If you already have experience in computing, tweaking pybricks or even Zephyr wouldn't be out of the question.
Why is it so difficult?
I've skimmed the source code for the pybricks firmware. As far as I can see, the code paths for the user-programmable RGB LED and the battery LED are completely different. The former is treated as a peripheral, but the later is treated as process events passed to the underlying kontiki OS.
So in order to make the battery LED user-programmable, first you would need to disable it at a lower level. Which means losing the default behaviour for that LED.
Why is this a bad idea?
When developing low-level firmware, the ways that the computer (the hub) can display information are very limited. I'm talking no bluetooth, no USB, no UART: a status LED is in most cases the only tool available. Losing that tool  is plain dangerous.
From a support point of view, letting a user fake the behaviour of that tool means that you couldn't trust problem reports. If a LED is stuck on a colour, how can you be sure that it's a problem with the OS, or maybe is it a problem with the user's program?

As far as I know, this is not possible with the default firmware and APIs currently. The primary hub LED is exposed as hub.led, but I don't believe that the other LED is accessible from user code.
It may be possible to access it in some undocumented way or via custom firmware, but I'm not familiar with any way to do this.


text:
Issues with Move Hub and Controller: first connected device works, but not both
I'm having issues with the move hub 88006, the controller 88010 and the Powered Up app.
The issue is the same on multiple devices.
Basically, whatever I connect via Bluetooth first is what works, but I can't get them both to work.
If I connect the hub first, I can program the hub and it works fine, but the controller block doesn't work (any button presses don't appear to register)
If I connect the remote first, the button presses on the remote register, but the hub doesn't react.
They both appear to be connected in the Bluetooth menu.
I have unpaired and re-paired multiple times, changed batteries, and tried my phone and tablet and the issue is the same.
Does anyone have any ideas?


text:
Fit motor to old tractor

I'd like to motorise this tractor I built from an old Lego book.
I've 4.5 volt motors. The model is 6 studs wide, the motor is only 4, and since the tractor uses big wheels it would be too fast. Is there a possible gearing from the motor to the wheels, which is only 1 studs thick that I could use?
I've also got a 9 volt motor, so would it be possible to use bevelled gear wheels to go through 90° to the wheels?

You'll have to be more specific. Which tractor? From which book? Which motor, exactly? A couple of photographs would also help.

Sealed motor, Fordson? Don't know what book as missing 1st page.

Hi Andrew! I took the liberty to copyedit your question for better readability; please give it a read and fix anything I might have misinterpreted, as your intention was not always 100% clear.


text:
Are LEGO Pneumatics gen 1 and gen 2 compatible?
I think they are at least partially compatible, but how much so? Can generation 1 and generation 2 cylinders easily and effectively be combined in one pneumatic pipe system? I.e. a set of pipes, tubes and other parts that exchange the air and are pressurized by the same pump. And how can possible problems be overcome?

https://www.wikiwand.com/en/Lego_pneumatics describes the various generations.
They describe V2 more as generation 2.1, pistons changed, but tubing and t-pieces stayed identical. Therefore I think it's safe to say that it's entirely compatible with all pneumatics from 1985 on ... The pneumatics prior to that is a different story...

I didn't know about gen 2.1, so I've updated my question to make it clearer. Can gen 2 pumps be used to create underpressure for the gen 1 pistons?

That was not necessary, it's merely the nomenclature the article uses, lego uses V2


text:
Cat D11 LEGO set won't start the calibration process
As soon as I start the calibration process in the app, the gearbox jams. It doesn’t do anything, just clicks and clicks (stripping the gears). Any ideas what the cause might be?

Possible duplicate of https://bricks.stackexchange.com/questions/16634/caterpilar-d11-set-42131-control-app-doesnt-seem-to-work. Please note that that question doesn't have an accepted answer but the actual answer is in the comments.

Most likely a mistake in step 87.
The two most common malfunctions are

clicking gears and no motion for the shovel, ladder and plow but tracks are working: redo step 87 meticulously.

Wrong engine activation in the gear box often happens. (often ladder moves instead of shovel) and calibration fails. This is a bug, the engine mistook the placement of the gears, and calibration doesn't catch it in the beginning. To fix, Cancel calibration, press the app button to lower the shovel and remember to wait for the gear to be changed, then retry calibration. If that fails again, try the shovel tilt and redo. If that also fails, then lower the plow and redo. It cannot be fixed by the ladder unless the gearbox was built wrong, (in that case you need to do 87-120 again).


text:
Is it possible to control the EV3 brick with a GUI on PC? If so hows the best way to go about it
I've been interested in controlling a machine remotely through a GUI and I am stuck in between picking Python or Java to do this project in but I also think the way I'm going about this would be all wrong.
The idea would work something like this:

Connect via Bluetooth
Create a simple GUI with buttons corresponding to the device attached (like a motor)
When a button is pressed then the device would activate

However I'm not sure if this would work?

If it doesn't have to be an EV3 brick, I would think WeDo would be what you're looking for (remotely, but perhaps not wirelessly). But WeDo has been replaced by Spike, and I don't know enough about it to say if it does what you want.

This is possible with the powered up app and powered up motors and hubs (either the technic hub or city hub, not spike, robotic inventor or EV3). Although I've heard that the environment is not intuitive and has a steep learning curve.

For mobile devices, there is an official LEGO app called LEGO® MINDSTORMS® Commander that can do this (Android, iOS, Fire, Windows).
If you want to write your own app, you will need to use the EV3 communication protocol.


text:
What is a novelty element?
TLG recently released the following update regarding clearing out the current backlog of PaB orders:

Starting week 34 (next week) the Denmark warehouse which processes "Standard" Pick a Brick orders, will be increasing warehouse staff and we should expect that between now and November, the order backlog is reduced and eventually eliminated. This forecast takes into account the upward trends that occur during specific events like new elements becoming available and the holiday season. Forecasts are predictions though...
Also starting week 34 we will start to increase the Pick a Brick assortment including the addition of novelty elements that launched from January through May 2022. These are not expected to launch in their entirety in week 34 but rolled out over a few weeks. We should then see novelty elements launching monthly moving forward.
It has been a long road for novelty elements launching and I recognize the challenge this creates. There is an end in sight though. Thank you for sharing your community members (and your own) concern along the way. Your voice has been, and will continue to be shared, with the relevant internal team in relation to this matter.

What does "novelty element" mean in this context? Does this term have a TLG-specific meaning beyond its general meaning?

This was a new term for me. It was clarified on the LEGO Ambassador Network by a member of the LEGO Community Team:

We have a lot of internal words that are not always known to the public. TLG considers new molds and recolors of existing elements (old element but new color) to be "novelty" for the first year they are produced.


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What is the best way to connect SPIKE prime angular motor to a wheel
I was wondering if there is a difference in the amount of torque transferred to the wheels from a LEGO SPIKE prime angular motor (45603 LEGO Education SPIKE Prime Medium Angular Motor) depending on:

using the axle to connect to the wheel or
Using 2 or 4 pins to connect to the wheel
Using a combination of pins and axle

The motor and connection points (axle and 4 holes for pins)

Wheel connected only by axle

Wheel connected using black pins (part 2780)

It feels like using black pins would be better, as the axle would have to turn a lot harder to rotate a wheel (torque about a point is related to distance from pivot point to the point at which force is applied). Does it apply in this case too?
The reason for my question: my Lego team is building a robot that needs to push on a bar. In this case doing things slower than faster can be better as the motion is more controlled. Would I be able to push with greater force using a 4 pin configuration vs a single axle?
Does this theory transfer to real life: eg cars, trucks, etc? Would the number of lug nuts and distance from center affect the vehicles motion/efficiency?

Torque will stay the same. The further from its center the less force a motor applies but the further from its center the greater the force contributes to the momentum of the wheel. The two effects cancel each other out.

TL;DR: Unless you do something quite extreme engineering, any coupling will do just fine and the motor will stall or the tire will slip before even a single axle gets to its limit.

The pins have a much higher shear strength than the twisting solidity of an axle. (I don't have the numbers ready, but I'm sure some have performed measurements regarding these values, and it seems intuitive too.)
Therefore if the wheel encounters heavy resistance, while the motor is turning very hard (as in, "almost impossible to achieve with standard LEGO parts" hard), then a single axle will fail by a lower torque than two or more pins. The coupling that can transfer the most torque before anything breaks is definitely the combination of four pins and an axle, maybe with additional 3mm bar pieces stuck into the pins.
But by the time you get to torques where this kind of coupling would be required, you are already working with such extreme gearing, that you need to employ specific building techniques suitable for high forces everywhere else too.

Responding to your edit:

In this case doing things slower than faster can be better as the motion is more controlled.

Sounds like you need a reduction gearbox, which would result in slower speeds and greater torque. This would mean that your motion can indeed be controlled better.

Would I be able to push with greater force using a 4 pin configuration vs a single axle?

As detailed previously, the method of affixing the wheel to the motor does not influence the force between the wheel and the ground (as long as it's a static coupling and not a force converter of some kind).

Does this theory transfer to real life: eg cars, trucks, etc? Would the number of lug nuts and distance from center affect the vehicles motion/efficiency?

The common theory is that real life vehicles need a gearbox as well to be able to operate in a wide range of speed-torque ratios while using the same engine. And their designers need to be mindful too of the rated limits of the parts used - but in your case LEGO pretty much did this job for you by producing motors and parts that can almost always be used together safely without calculating shear and torsion strengths.
An 18-wheeler truck has a lot more wheel lugs, as the forces generated are a lot larger than in case of a two-seater minicar, therefore requiring more material to ensure they don't fail even under the heaviest loads (emergency braking with full load at highway velocities). With both vehicles the lugs act as a 1:1 static coupling between the axle and the wheel, just the range of forces (or torques) that needs to be handled safely is much wider.
Nevertheless, you can easily set up a small experiment, where you stand a kitchen scale on its side between a fixed object and your bot, and measure the force your bot can push the scale with. This would help you see the lack of difference between the single axle and four pin versions, and later on would be useful to test different gearing solutions.

The reason for my question is not to figure out how much force before things break, but instead to figure out which configuration will give me the most pushing force (think snow plow like configuration). So would I get more pushing force with a 4 pin configuration at the same speed as opposed to a single axle configuration?

The connection type won't change the amount of force delivered.  4 pins would require more force to break; but unless you replaced the lego motor with one from a power tool and clamped the wheel in a vice you're not going to be able to deliver anything close to enough force for the yield strength to matter.

@RajRao Exactly as Dan is writing. In order to change the force (torque) delivered, you need a force-converting mechanism (gears, pulleys, crankshafts, etc). Then you can exchange force against displacement in either direction (more force but less travel or more travel with less force - like a transmission of a car or bicycle). A passive coupling will always transfer 1:1, unless its rated forces are exceeded: then it breaks or deforms.

Love your suggestion of using a kitchen scale for a test. Will test and report back

yes, thanks for your feedback


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What are the small numbers on old LEGO instruction booklet covers for?
Along with the set number, my old LEGO instruction booklets have a larger number in a smaller font on them as well. What do these numbers represent? What are they for? Unit/serial number?
This booklet for example:

It has "120733" written on the right in the black border at the bottom, in a font about half as high as said border. You need to zoom in to see it.
My newer sets' instructions don't seem to have this.

I'm not sure if this has any relevance, but Brick Owl use this number as the Item No. for instructions. see 8034

Such identifications exist not just on building instructions but on other printed items like catalogs, brochures, leaflets and so on. I don't have anything to base my answer on, but my guess this is some sort of "inventory ID". Just to make things easier to store and refer to instead of using using full name like "Building instructions for 8034".

And instructions could have been different for different regions (A4 vs. Letter, for instance),

I agree. Having an article number or ID number for printed materials is a very common business practice. It allows you to treat the materials just like any other item for warehousing/shipping/manufacturing purposes. When you look at recent Lego packing boxes you see next to the barcode a line "Item: XXXXXX"with a 6 or 7 digit number. This probably serves the same purpose for the box itself.


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Help with Lego Typewriter 21327 - can't get the carriage mechanism working
Two AFOLs here who are stuck on the Lego Typewriter build. We have built large and complex sets before, but this one has us stumped. We have now rebuilt Sections 5-7 twice, but we can't get the carriage mechanism working.
See the video at Reddit. All of the gears seem to be turning, and the carriage moves when we manually press the lever next to the lime green part on the left side of the back (looking at the front). However, the keys don't move the carriage. When we push the carriage all the way to the right as shown on page 170 of the instructions, typing on the keys does not move the carriage back to the left as shown on page 171.

The keys don't seem to be striking any of the mechanisms. The grey and blue pieces (closest to the keyboard in the back section) are moving, but the keys and the carriage don't seem to be connected. It's hard to describe, but the video shows the problem more clearly.
Can anyone help troubleshoot this?

From what I can see in your video, the carriage mechanism itself doesn't appear to be the problem, but rather the linkage between the keys and the carriage.
Pressing a key should move this assembly from step 152:

In your video, it looks like the left side of that assembly doesn't move freely. It should move when a key is pressed and activate the typebar to strike the page. I'm guessing that something is off with the way that mechanism is built or installed.
One thing to check would be the orientation of the black elements in step 134:

These should be able to rotate easily around the gray part.

We'll take a look.  Thank you so much!

We had exactly the same problem. This set has 2 elbow pieces 6262905 and 6261387. The directions do not specify which one you need for the step 199. However it has a 3 imprinted on it.

These 2 elbow pieces have different angles. So you need the one with 3 imprinted on it or piece 6261387. After we switched that piece it all works.


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IR remote 8879 - cannot control speed of the motor
I got the 7938 train set for my kid.
I hook up the battery to the receiver and try the IR remote 8879 with it.
The motor starts running/spinning, but I can not control the speed with the orange "joystick" knobs on the remote.
Whether I turn the wheel clockwise or CCW, the speed just ramps up (to the maximum speed, I guess) faster and faster.

Fresh batteries are installed
Same channels are selected (also tried all four channels)
Switched between red and blue connections

Any ideas why this may be?

For what it's worth - I have seen that happen a few times with my remote as well (albeit just on one of the joysticks iirc), but couldn't reproduce it just now with several combinations of IR receivers (both v1 and v2 fwiw) and motors. I've always suspected a faulty contact, but have never found out for sure.


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Adapters for Lego Duplo and Mega Bloks
Similar to this question I am interested in combining Duplo Lego with Mega Bloks.
I want to have full compatibility, i.e. being able to put Duplo on top of Mega Bloks, which requires some type of adapter.
I am looking for BUYABLE adapter pieces (not self-made via 3dprinter or such).
Does anyone know a source?

I found that Lego has a (discontinued) system called "Lego Primo" with similar round studs. It does have adapter blocks for Duplo (marked with red rectangle):

Can anyone confirm that these do / do not fit the Mega Bloks studs?
Although they are discontinued, they can still be bought used. So if they fit it would be an option for me.

There is an unconventional type of adapter being sold on Ebay (seems to be just a single offer, used):

Has anyone ever seen these somehwere else? Maybe even in real life? They do not look 3d-printed, they look injection molded (like Lego and Mega Bloks). So there might be someone producing them (or having produced them) commercially...

I've linked to the eBay item your picture comes from, in order to let others see the whole listing with all images. Note though that the listing explicitly mentions how "They are extremely hard to find." I can easily imagine someone having set up an injection molding line for these parts, and only producing a handful of them before getting hit by C&D letters from both TLG and Mattel - thus limiting the availability of these parts severely.

I have several of the second (white) adapter you show in the photo, from my original 1990s Mega Bloks sets. I have the original Ritvik Mega Bloks (the only size now sold) as well as a Ritvik Mega Bloks set that is almost identical to Duplo blocks (sold in the early 90s, mine are marked 1992), with the white adapters made by Ritvik.

Primo and Mega Bloks are not compatible.
The Primo piece loosely fits on a Mega Blok piece:

But the Mega Blok piece does not fit on the Primo stud.

As for the adapters in your second photo, I have seen them many times in used toy collections I've bought; unfortunately, I don't think I've ever seen them new in the package to give you a specific reference on how to buy them. But I've always assumed they were an actual Mega Brands product.
I have a 2x2 (or 1x1) and 2x4 (or 1x2) in front of me. The smaller says 430 and © 1988. The larger says 439 and PAT PEND and © 1988 and (tellingly) Ritvik. (Ritvik was the maker of Mega Bloks.)


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What Lego-like head is this, with a blue slit over the eyes?
It has no facial features. Has a blue slit. No helmet and no hair

That's not Lego - the chin shape gives it away. I think Kreo makes that shape, but I don't know if anyone else does.

Following the lead from RSchulz that this might be Kreo, I found this head in the Dinobot Slug Custom Kreon set.

Nice! I looked at a lot of Kreon heads, but never saw that one.

@RSchulz I actually found Scorn first, but I wasn't 100% sure it was the same head, so I was looking for photos without the helmet.


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Looking for set number - lots of off green flat pieces
Looking for kit that these bags belong to

These are from The Child (75318) set. Identified by unique combination of two elements in Sand Green color:
Slope, Curved 2 x 1 x 1 1/3 with Recessed Stud

and Slope, Curved 4 x 1 Inverted


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What set is this from? (spiky transparent blue with axle hole in the center)
Does anyone know what this piece is? I have asked people around if they know what piece it is. They didn't know it. It has an axle hole in the center.
All help appreciated

Looks like part 98578 Hero Factory Weapon: Spiked Ball, Half in transparent dark blue (found by a bricklink search for pieces named "half" in trans-blue).
It appears in two sets: 70202-1 "Chi Gorzan" from Legends of Chima, and 45560-1 "EV3 expansion set".

Given that the posters previous question was about programming, I'd think that the EV3 expansion set is more likely. Also regarding ownership, I've bought half a dozen of this set. At the time, there were some online stores around here that offered them significantly cheaper than RRP and the boxes were ideal part donor sets for anyone interested in technic/mindstorms....

That's a good point. I'll rephrase.


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What set does this bag belong to? Mostly black with some red and yellow pieces
Bought these at a garage sale.
Picture of bag.  5.  121r8

I can see a Black Wedge, Plate A-Shape with 2 Rows of 4 Studs and a Dark Red Wedge, Plate 4 x 2 Left. Those appear just in two sets, and I'm fairly convinced that you've got parts of Ninjago set 70653-1 Firstbourne:

The inventory of that set is consistent with other parts seen your photograph - there's Wedge, Plate 3 x 2 Left in Bright Light Orange (easily mistaken with Yellow), Dark Bluish Gray 1x2 Technic Brick 1 x 2 with Holes, barbs in Bright Orange, and others.

Thanks for thoughts

I was mistaken! There's like 5 shades of yellow, and since the lighting and white balance of your photograph is... not the best, I was fooled by the bright light orange colour.

Set 70653 is also consistent with the note written on the bag that 2x part 35633 was taken out of the bag. And there's 6 of those in that set (in Black).


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Where can I find the value of this seemingly rare MEGA BLOKS tree and whether there are additional parts?
I am looking for a value on this MEGA BLOKS item and whether there are additional parts to it.  I have searched AM05829 AND AMO5829 on internet, ebay, and etsy and have found nothing.  I seem to be able to attach only one photo, but the previous item # is stamped on the tree base.

Looking for the tree by descriptions "mega bloks cartoon tree" and "mega bloks happy tree" I came across this listing with photos of the set. It's from a Dora the Explorer set with 44 pieces.

You are so-o-o awesome!   THANK YOU!!!


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Small torso cracking
I have a ton of LEGO Minifigures I am putting up for sale on my Bricklink, but I just noticed almost every single figure looks as if there is a crack right under the arm starting at the armhole and ending right under it. It’s barely even there. It looks as if it’s part of the figure. I'm not sure what to do. I just wanted to reach out and see if this part is normal or not.

Hi Ava, welcome to Bricks SE. I can confirm that many of my figs have cracks as you describe, especially the older ones. However, as it stands, this question needs a bit more clarity as to what you are asking.

Hi thank you,So basically what I’m asking is can these figures be concerned used condition with out cracks? I just opened a new Minifigure just to see and it seems to have a “crack” too.  Is it just apart of the plastic?

As a buyer on Bricklink I expect used item to have some reasonable wear. However if there any visible or known imperfections they should be noted as this would change item condition from "used" to "damaged". And you don't want to end up in a situation your your customers complaining about wrong condition of items you have for sale and leaving negative feedback. Cracks, tooth marks, a lot of scratches, miscoloration, warping are all considered to be characteristics of "damaged" elements.
From my experience it is not worth selling damaged bricks unless they are very expensive and damage is somewhat manageable.


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Help identifying bricks - non lego
Please help me identify this non-lego brick set. I got this bricks set in the 1980's and had a lot of fun with them. But I cannot find what they are. I lost the box, but i remember there was a castle pictured on box.
Build quality is quite good and they still stick and fit well. Brick is exactly 1x1cm (black cube, white ones without connector ends) and there is also "plating" that can attach to brick and small window.

I'm not sure if these elements could be considered as "LEGO like bricks". Looks more like a (distant) variation of K'NEX instead.

I'm fairly sure that's Fischertechnic (https://www.fischertechnik.de/en/). I'll see if any old catalogs are available.

my first thought was also Fischertechnik, but their old blocks are mostly gray

I don't think it is fishertechnik, the black brick lacks "pin" and center ridge is not made to lock the pin found on fishertechnik bricks. But maye it is an older set.

Definitely not K'NEX and also does not look like old Fishertechnic set. It may be a knockoff of sort, bought in former Yugoslavia in '80.


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Aircraft with missing wing part
I have the body and a 1 side of a wing span, missing the other side. There is a cylindrical thingy with a light lime green "cap". There is also a winch inside the body.
Hope this helps.

Please add a photograph (or two) of the incomplete set. The text description is just not enough.


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Railway track layout - is there a method to say if track layout meets up

I'd 2 circles of original blue railway track, lost 1 inner, bought mixed batch of track off eBay, as more inner than outer bought more track & to get discount 12 outer & 4 inner to bring N° of outer & inner = at 1 pair short of 4 circles. So I set myself the challenge of using all in 1 layout with no dead ends. I'm emptying old caravan so room there. 63 curved, 14 straight pairs, 2 crossing & 2 points.
My question, is there a maths equation or computer program to say if track layout meets up? Instead of trial-&-error method. R10L4XS2R8S1PR1XS2R12PXR1L2XR7S3R4S1R1S1P were R=right, L=left, S=straight, X=crossing & P=points.
Noticed in Ideas book, 3/4 circle, then 2 other way then 1 straight, Then other end 1 same way, then 3 other to become touch & parallel to other to go to points.

It would have been an idea to give some indication of where on the picture your textual description starts. I also think it's wrong, the short stretch between the two crosses are noted as "R1L2", but there are four pieces on the picture (as far as I can see, it becomes "R1L2S1" in your notation). Your textual description also misses a bit of the layout. But a train would get stuck on the last part of the description.

As railroad switches have three connections, a notation like yours is not really possible.

This might get a better theoretical response from MathematicsSE.  They've got a bunch of train-related questions already, but I didn't see this one asked yet.  https://math.stackexchange.com/search?q=train

@chicks Yes, this seems like a combinatorics style question. With a finite amount of rail pieces you can built X many valid routes. These problems can be quite complicated but it's easy to identify a few rules that must be followed such as using a minimum of 8 track pieces to form a loop. Straight pieces, switches and crossovers all add a lot of complexity.

Yes, I made an error, sorry.

For software layout options there's BlueBrick as mentioned in this related answer
Alternatively both SCARM and Winrail support LEGO 4.5V and LEGO 9V layouts, while SCARM also supports LEGO RC:
SCARM Library List
WinRail Library
It's been a while since I've used either, but WinRail seems to be somewhat dormant now.


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Little figurine identification - little grey robot with red eyes

I got this little fella from a thrift shop. I just thought it looked cool, but I have no idea which set it originates from. Can anyone help?

They way it is built makes me think this is a custom creation (MOC).

As you can see from this search, of the four sets which contain three of these parts, none include all the parts. This must be someone's own creation (MOC) as identified by Alex.


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Bag of LEGO pieces that I don't know - lots of earth tones, some black and grey
Do you guys know what these LEGO pieces are? Please tell me.

Based on

Sand Green Arch 1 x 3 x 2 Curved Top
Dark Tan Brick 2 x 4

The only set on BrickLink with both of these seems to be 75318-1 The Child

Note that there are also pieces in that pile that do not belong to set 75318, like the foliage piece in the top right corner. No guarantees that this is indeed the complete set.

At least what's pictured, it's definitely not the complete set. I've got this particular set and there's 8+ bags in total and a number of the bricks shown are not part of it.

@RoddyoftheFrozenPeas does this set have any red? That's the biggest differentiator I see in OPs image that makes me think it's not The Child set...

Only one other set (7572) has at least 6 Dark Tan 8x8 plates, and it doesn't look anything like this.

@BruceWayne Yes, there's some red pieces; they're structural bits buried deep inside the model. Confused me why they were so outside of the color palette when i was building it. The main thing that sticks out as not being part of the set is that weird green leaf-like piece top right.


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Can someone identify these Lego sets? White with large transparent blue walls
I am looking for some help to identify the sets to which these pieces belong. Have been searching for some time without luck…
Any experts that can please assist?
Thanks

First one is from Arctic Mobile Exploration Base (60195) since there is only one more set that has more than 3 pieces of Trans-Light Blue Rock Panel 2 x 4 x 6 and that set doesn't have included white pieces.

The rest is from Defense of Crait (75202), which was easy to identify since there are just five sets (by the time of this answer) using Light Bluish Gray Brick, Round Corner 3 x 3 x 2 Dome Top.

Wow! That is amazing! Thanks Alex! Really cool forum!!!

@Henning If the answer has helped you, please mark it as accepted. You can learn how to do that in the [help].


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I found these parts but have no idea what sets - lots of grey and black, looks like Star Wars
Can anyone identify what sets these parts belong to?

That dish in the baggie was only ever in one set: 7748 Corporate Alliance Tank Droid

The decorated windscreen below seems to be Windscreen 6 x 6 x 3 Canopy Half Sphere with Dual 2 Fingers with SW Sith Fighter Pattern which was only in one set: 9500 Sith Fury-class Interceptor

I wonder if that base on the lower left is 10186 General Grievous - UCS

The one at the top is cut off. But based on

Dark Bluish Gray Tile, Modified 4 x 4 with Studs on Edge
Dark Bluish Gray Wedge, Plate 4 x 2 Left
Light Bluish Gray Technic, Liftarm, Modified Bent Thin L-Shape 3 x 3

The only set with all 3 seems to be 75104-1 75104-1 Kylo Ren's Command Shuttle

The one on the lower right with the orange seems to be a freezing chamber, but I might not know which one:
Based on

Dark Bluish Gray Plate, Modified 1 x 2 with 1 Stud with Groove and Bottom Stud Holder (Jumper)
Dark Bluish Gray Wedge, Plate 4 x 4
Trans-Clear Plate 1 x 2

it would either be 75222-1 Betrayal at Cloud City or, more likely, 75137-1 Carbon-Freezing Chamber as Cloud City doesn't have any 32474 Black Technic Ball Joint which I think I see in the photo.

Nice finds! The blue tower on the left is from 6873, the black curved slope construct looks much like the top of 75227, and the small build with door on the right looks like the 'fridge' in 41119.


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What is this 2x2 figure with a hollow base?

What is this 2x2 figure called? I want another one but I don't even know what to search for. Is it something before minifigures? Is it even LEGO?

I got some clues from my sister. It's not a boy, it's a girl. Basic Figure Finger Puppet Female (bfp001) from 1980's LEGO Basic set
https://www.bricklink.com/v2/catalog/catalogitem.page?M=4224c01#T=S&O={%22iconly%22:0}

They can be ever so fun to put on your fingers.

I remember those from my childhood!


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What is this 2x1 decorated brick with green screen?
This is not a slope part, just a plain white 2x1 brick with decoration.

That's Brick 1 x 2 with TV Screen and 3 Buttons Pattern

It was part of a (BrickLink-labelled) minifig?! https://www.bricklink.com/v2/catalog/catalogitem.page?M=alp007

@RSchulz that was just one of its uses


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Upload 2 old Lego books

I've scanned 2 old Lego books of images & some instructions and can now see them better on PC. Made all animals on page 9 (in photo) apart from 1 small dog, using Lego I've had for years. Bought more & built more. Taken some apart to re-use. Don't know what the books are called, or their year, late 50's/early 60's. Who would like images of them? As I think most then better to put on a website. I've 'cut' pages of them on PC. Written notes for some. Some changes: the flag on the yacht, women's skin colour, smaller tusks on the elephants.
The lion, what = that flat thing behind his back legs? 2×4 bracket with 1×2, but then it can't be 2×4 his legs are attached to.
So books = Ideas Book N°2 & N°3, N°1 (mostly like N°2) is on the internet. Aka 238-1, 238-5 & 238-8.
Found some pages of Ideas Book N°2 on Worldbricks, including p.1 I was missing, but pdf file of all page = wrong book.

I’m voting to close this question because this is not in an answerable StackExchange format.

OP should contact BrickSet (www.brickset.com) as they have a database of all LEGO catalogs. They might not have these catalogs yet.


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How do I identify which minifig is in a blind bag for The Muppets series of figures?
How do I identify which minifig is in a blind bag for The Muppets series of figures?
I would like to know what is the best way to know which minifig is in the bag.

A better format for this, and more likely to keep it from being flagged to be closed, might be to pose the initial question something like "How do I identify which minifig is in a blind bag for The Muppets series of figures?" and then answering your own question with the relevant information. Possibly flagging it as a community answer to allow others to update the answer as more information is available.
As it sits right now, this doesn't quite fit the format for this site and is at risk to be at least downvoted, if not removed.

I’m voting to close this question because this is an Answer rather than a Question. The content of this post is valuable, but it has to be an provided as an answer to some sort of question. I would also like to note that it is perfectly fine to have a question answered by the same person as long as the question (and answer) fit the scope of Brick.SE

Thank you all for your comments. Changed the format, hopefully with better fit to Brick.se

@Saariko Thanks for sharing and for taking the time to edit your post. Welcome to Bricks.SE!

I did, I went ahead and purchased a small digital scale, with .01 grams of precision.
I weighed the bags and identified them. Here are the results:
Most have unique enough weight. For the ones that are close, you can feel one of the items within the bag.

Minifigurine Character
Weight (g)
Feel for

Dr. Bunsen Honeydew
9.65

Kermit the Frog
9.85

Gonzo
9.96

Beaker
10.05

Janice
10.73

Waldorf
10.88

Fozzie Bear
11.22
Mic stand

Statler
11.24
Laptop

Swedish Chef
11.57

Miss Piggy
12.06

Rowlf the Dog
12.55

Animal
14.18


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Sources of minifigures with plain, classical faces
For Reasons™, I am looking for current sets that have minifigures with the plain, classical faces:

However, if I look at the current selection on the Lego website, all the accompanying minifigs have stylized faces. The only currently sold set I have seen so far with plain minifigs is Ikea's BYGGLEK.
Short of hunting for deals for old, retired sets on eBay, are there ways for me to get sets that have plain minifigs?

(Also, I've last played with Lego as a kid, but only started to get back into it after 25 years, so I'm not hip on what's de rigueur these days, and would appreciate some handholding.)

There are several options (moulds) you can choose from:

Minifigure, Head Standard Grin Pattern - Hollow Stud is the latest,
currently available option. List of sets with this piece included.
Minifigure, Head Standard Grin Pattern - Blocked Open Stud was available up until 2016. List of sets with this piece included.
Minifigure, Head Standard Grin Pattern - Solid Stud was available up until 1996. List of sets with this piece included.

Adding to the answer provided by Alex, there is also the option to buy this head from the pick-a-brick section on the Lego website.
Specifically, part number 9336 "Minifigure, Head Standard Grin Pattern - Hollow Stud" can be found at https://www.lego.com/pick-and-build/pick-a-brick?filters.i0.key=variants.attributes.designNumber&filters.i0.values.i0=9336

And cheaper than on Bricklink.


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Can you identify this mini figure with black Darth Vader-like helmet
I got it in a big box of pieces.

This is NI-L8 Protocol Droid from set 75300-1 Imperial TIE Fighter.
Note that it is similar to (and shares a head with) Death Star Droid but that figure doesn't have the colorful wires in the waist area.


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What's inside a linear actuator?
The two linear actuators that I know, 61927c01 Linear Actuator and 92693c01 Linear Actuator Mini, have a built-in clutch (that makes a clicking sound when feeding the actuator torque when it's fully retracted or fully extended).

What's inside the actuators? Is there a worm gear inside? How does the internal clutch work?

There is definitely a worm gear and a clutch inside, as reported by the (now defunct, but luckily archived*) TechnicBricks blog:

The orange part is the input and engages with its serrated surface the pins of the white cylinder. The flexibility of these pins allows the rotation of the input axle while the actuator shaft is blocked - providing the clutch functionality.
The inside of the white cylinder has grooves in it which then engage and drive the worm gear structure of the actuator shaft - provided the end of the shaft is prevented from rotating. Otherwise the cylinder and shaft just rotate together.
The Eurobricks forum has a thread detailing the differences between the various iterations of the linear actuator, with the following images of the internal components as they got updated based on customer feedback:

* Have you considered donating to the Internet Archive?


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When bricks with bottom holes were released?
I always try to build my sets with bricks from that era. The older ones and their release dates are pretty well known but what about that D variant in the picture with bottom pin holes ie. the modern LEGO block? When did we start to get them? From my understanding 80s sets did not have them yet but were they available already in the beginning of 90s?

Please [edit] your post to identify the source of the photo.

@shoover I took the photo myself :)

Do you mean "hollow tubes" when you say "bottom holes"? Then TLG has gone a bit back-and-forth on that for certain elements, and never considered them different elements, so they might have been mixed in some sets - and I have no year(s) for when it was (re-)inroduced/dropped for specific elements.

Well, yes and no. Around the 90s is a pretty big timespan. The 1995 social media quote is a bit better but there is no link to any social media post it uses as source. Also, would be great to get a more direct answer from a reputable source.

I don't see the cross support on C, you're missed 1 out. Was going to say that all of what I call pillars, not knowing that hollow in future, others call them tubes, have cross support, but now see 1×8 only on 1 2 4 6 & 7.


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Salt Lake Temple: Downward facing triangles
Another question in my SLC temple series:
How can I replicate the downward facing triangles in the stonework of some of the spire/columns.  Currently I'm planning on just using cheese slopes but those are kind of square.  I could maybe use quarter tiles but they're not quite the same either.

How wide is that section gonna be, 8 studs maybe? Off the top of my heads, plain studs-out might just work.

Or SNOT 15208 1x2 plate with 3 teeth.

Please post some pictures of your attempt to replicate this. It would give a sense of scale and accuracy we are looking for.

I'm not sure if you could engineer this into a question, but I'd love to see the end result of your temple when you've finished!

@NeilTarrant that is why we have comments and chat!  :-)

This really depends on the scale you're going for. At least roughly how wide is that section/tower going to be in the final model? A few studs? An entire 32-footprint? Anything in between? It largely depends on how detailed the whole rest of the building is.

To answer Neil Tarrant's question, I post updates for this build on the lego creations group at https://www.facebook.com/groups/519139904928934

Judging by a previous question by @MonteGardner, I'll assume that the build is mainly in light bluish gray ("bley") colour, and the distance between the columns of a tower (the length of the downward triangle strips) is 8 studs.
I'll suggest using 1x1 plate with tooth for the triangles (with some SNOT supports and tiles for the battlements), plus slope 75° 2x2x3 for the pyramid endings.

In a comment on the question, you suggested "1x2 plate with 3 teeth", as that would give 12 "teeth" on 8 studs, and there are 13-14 "triangles" on the picture that would come closer.

Unfortunately "1x2 plate with 3 teeth" is not available in light grey colour.

Ahh, that's a good reason not to choose it.


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Help me find the id of a part - two clips back-to-back
Help me find the id of this LEGO part please!

Hi c1oz7 and welcome to Bricks.SE! Please take the time to read the [tour] and the [help] pages to learn the local customs which will let you write great questions.

This is definitely not a LEGO part, but one from a compatible brand. Looks like a Brickarms U-Clip.

Can you tell me where I can buy?

If you click on the link provided, there is literally a section on that page labeled "where to buy."


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Identify this part: two 2x2 plates connected by a strip
Bought a Bulk Lego lot and got some older (1960-1970s) Lego mixed in.  Came across a plate that is best described as a 2x2 plate attached to another 2x2 plate by a thin strip of plastic kind of like a barbell.  The piece is about 2 inches long from plate to plate, I have never seen the this piece before and it is stamped Lego on top of all the studs.  Any help in identifying this part?

Hi Brandon and welcome to Bricks.SE! Please take the time to read the [help] and [tour] pages, then attach a photo of the part to your question. Thanks!

That's gotta be part 650 2x7 hinge plate with 3L bendable coupling nylon:

It only appears in sets from the 1960s, as a means of attaching a vehicle to a trailer.

I was half-way into typing he same answer and then you posted yours. Can't be anything else.

I didn't know the time range but this is the part that instantly came to mind even though I haven't done anything with Lego since the early 70s.

Depending on the scale it could be a Duplo Bar with 2 x 2 Plates on Ends.

"The piece is about 2 inches long from plate to plate" I don't think it could be Duplo, unless that's very weird wording for being the length of the bar alone.

@RSchulz Yes, "plate to plate" could be interpreted as the distance between the inner edges, but TBH I have no idea how long this Duplo bar is (or how it relates to 2 inches).

Well, each of the 2x2 Duplo plates is about an inch across by itself, so that bar between would be right around 2 inches by my eyeballing it.


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Need help to identify a 1x6 support or wall piece
I have looked through pick a brick to find it. I even went searched up the specific set for it but still can't find it.

This is Support 1 x 6 x 5 Girder Rectangular (64448).

The element ID for this is hard to make out in the photo, but it is 6186296.
PaB won't have all elements, especially if they aren't currently in production. This element hasn't been used in a set since 2020. It was last used in the Saturn V remake that is no longer in production.
You can search by element ID on other sites such as Brickset, Rebrickable, or Bricklink to lookup information about a given element ID.


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What is the carbon footprint of running a Spike Prime robot?
We are trying to calculate how much carbon is emitted from running a Spike Prime robot off one charge (roughly 8-10 hours)?

I dont’t think Bricks.se.com is the right place to get answers to homework questions,

I’m voting to close this question because this is asking the community to complete a homework assignment

no, answers are here

@PhilB. Even if the question is about a homework assignment, it has a clear connection to LEGO bricks with a less-known but exactly available data (the total amount of energy in a SP battery), which is essential to calculating the answer. Providing this information would be squarely in the focus of Bricks.SE - but solving the assignment on the other hand is of course not. I'd suggest editing the question to emphasize this information need.

None, running the robot doesn't produce any carbon as it doesn't run on fossil fuels but consumes electrical energy.
Producing the electrical energy to charge the battery does have a carbon footprint, so I'm going to assume you meant to ask that.
I'm also going to assume that you completely deplete the battery before you recharge it.
Specs say that the battery capacity is 2100 mAh at 7.3 V...
Hence, power usage is 2100 x 7.3 / 1000 = 15,33 Watt hours (Wh) = 0.01533 kWh
How much carbon is emitted depends on how the electricity to charge the battery is produced, which basically depends on how electricity is generated where you live.
assuming you are from the US I found the following data:
https://www.eia.gov/tools/faqs/faq.php?id=74&t=11
Which states that 0.855 pounds of CO2 is produced per kWh
So I get 0.01533 kWh times 0.855 ~=~ 0.0131 pounds = 0.209 ounces

Thanks for this answer!

The official rechargeable battery for the large hub has 2100mAh capacity at 7.3V - This lets you calculate the total watt-hours in one full charge (let us know if you need help with this), which you'll then need to multiply by the CO2-factor of your current local energy provider.
This last part makes the question ultimately not answerable in a universal way, as you'll get entirely different results if the electricity you use comes from a hydro power plant or from a plant burning brown coal.


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Does the LEGO Mario app support three player?
There are 3 playable characters currently in the LEGO Mario theme (Mario, Luigi, and Peach).

The app makes a two player mode available. Is it possible to play with all three characters in the app?

I ran into this issue recently. Unfortunately, this is not currently supported in the LEGO Mario app. Any two characters can be used together (even matching characters), but you can't connect more than two characters simultaneously.
This was clear in the app update that added support for Peach (emphasis added):

LEGO Peach comes with a bunch of new reactions and can be connected to either LEGO® Mario™ or LEGO® Luigi™ (sets are sold separately) to win bonus coins for teamwork.

Subsequent updates have not upgraded the multiplayer mode to support additional players.


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What scale are the Mini Modular (10230) buildings?
I'm newly returned to Lego, and, holy cow -- It's a different world than the one I left in the 80s.
I always wanted to build a Lego city. The constraints of childhood kept that endeavor at bay. But, now that I have a kid of my own, the door has reopened. Never mind the fact that he is barely old enough to hold a Duplo.
I'm shooting for a modular, micro/mini city. But one of the things I'm struggling with is determining the right scale for me. At first I decided to pursue the "Micropolis Standard." Simple enough. Small enough. And well supported. The scale is roughly 1:285. If I did my math correctly.
To get my feet wet I bought and built Lego's 2014-15 Bricktober Mini Modular series (40180-40183; 40141-40144). I think these are roughly in the ballpark of the Micropolis scale.
But then I bought and built Lego's Mini Modular set (10230). The buildings in it are quite a bit bigger than Micropolis scale, which allows for more detail. Detail that is simply tremendous. I immediately fell in love.
Now, I know that Lego doesn't have a fixed scale. I've learned that Minifigure scale changes depending on measured dimension (height vs. width of a thing). And in any case, scale is "violated" all the time to make things look better. Compounding this, it appears that 10230 is about quarter scale when compared to the rest of the Creator Modular series. The buildings in 10230 are scale models of scale models with some oddball features.
If I can figure out the approximate scale of 10230, my hope is that I can upscale a variation of the Micropolis Standard to build my city. But I need help validating my assumptions.
At first pass, I've calculated the height of a plate to be roughly 2ft. Which would put the scale at 1:190. Real example: The big brother version of the Parisian Restaurant (10243) has floors between 7-9 bricks high. Which would roughly be between 10.5-13.5ft in real life. Which seems about right for older European buildings. At the scale I'm shooting for, these same rooms should be between 5.25-6.75 plates high. Which, when compared to 10230, and rounding up, seems about right too.
It also is a 1:1 to Lego Units, which would be pretty great.
Surely someone, somewhere has done this same exercise. Can anyone point me to that resource? I've looked -- micro, mini, modular... these are all pretty generic, all encompassing terms. There's a lot of content out there, but almost none of it speaks directly to the scale of the mini modular set. So any assist is greatly appreciated.

You already have put quite a lot of thought into this and it definitely is an interesting question. However, I don't think it is answerable as stricly as you might hope, but I don't think that's a bad thing actually. Your computations aren't that far off, though.
You already realized that figure scale in LEGO is a strange beast due to the rather weird proportions of LEGO figures. So when using specific Modular Buildings for reference, you already have a problem with the minifig version not being entirely accurate to reality. Add to this the fact that storey heights can also vary significantly in reality. Trying to pin that to an accurate scale might get rather difficult. That BrickArchitect article is a good start, though, and a rough approximation that I tend to go by for figure scale is indeed 1:42, which is also conveniently about half of H0 scale (1:87), as known from the model train world.
But then you also have the problem of abstraction. The Mini Modulars, albeit about a quarter in size of their bigger brothers, also might abstract some elements in order to get a better representation of the original's overall style less than its accurate dimensions. But if we go by quarter scale, we could say it's maybe around 1:175, which isn't that far off your 1:190. That would also mean a human would be conventiently around 1cm tall, which is also roughly over 1 brick, whatever measurement you prefer. However, the exact number doesn't quite matter too much. What is more important, and the Mini Modulars demonstrate that too, is picking something that fits the pieces. For example using SNOTed 1x2 tiles as doors is a common technique. Also the premade 2x2 windows make for useful elements. So ~2 bricks for one storey isn't a bad idea, which would also match with your results.
For some more practical examples, I have seen a few YouTube cities using an approach inspired by the Mini Modular style, too, and working with 8x8 modules. This conveniently fits to the LEGO grid of 32x32 basplates and the like. It also has other advantages, like simple 2-lane roads being 6 wide with 1 stud sidewalk on each side, which in turn fits a road built sideways and made up of 7 plates per lane with a neat 1 plate striping in the middle. This can then conveniently host 2-wide cars, or the "CITY Advent Calender scale" ;-). For people they tend to use either nanofigs (what BrickLink calls "trophy figures") or builing something about 4 plates high, which also fits to the scale not too badly.
Afterall, even the Micropolis standard isn't as strict as everything always adhering to 1:285. You can really put anything between 1:250 and 1:300 into a Micropolis layout and maybe even more. It just has to fit the overall aesthetics and be reasonable to build. You don't want to build cars that are 1.25 or 0.75 studs wide, you want to put a tile onto a jumper and have an iconic and recognizeable micro car. I haven't worked too much in Micropolis myself, but I made the experience that you shouldn't pain yourself too much with thinking if that fence should be one plate higher or lower rather than if the overall look fits and it's practical to build. In fact I've even seen houses in the scale of the Mini Modulars put into a Micropolis layout (she even uses her own micro versions of LEGO Modular Building sets) and although they can look a bit big if you try to compute the exact scale, I think it works very well in the overall layout.
I personally also try to compute an actual scale for at least my Architecture models that try to get real-world proportions as close as possible, but even there it's not always easy to compute that to an exact number based on abstractions that the LEGO system requires. You might have to build it higher than it is wide or you might have to build that window smaller than it really is. And with something like a freely designed micro city, it's more important you have a solid idea how to build roads, cars, doors, and whatever in a convenient way and everything fits well together.
So on the bottom line, have a rough scale in mind, but don't get hung up on the exact number. In fact, what's more practical is having various numbers in mind, for each of the different use-cases, and then pick whatever fits to what you're building. I.e. establish a reasonable standard for major elements that works well together and that you're comfortable with. If people are then actually 1:175, cars 1:150 and trains 1:200 doesn't matter all too much because noone will actually do those computations as long as you got a coherent model. The ideas for how to build it from the pieces you got will then come with some experience in the scale. Some easy guidelines for Mini Modular scale (which also fit to what you came up with) would probably be:
2-brick storeys, 1-brick people, 2-stud cars, 1.5x Micropolis, 1/4 figure scale, or anything between 1:150 and 1:200.

You are spot on. The critical aspect is consistency across elements. And scale matters less than doing what looks good. So, do that. Also, I realized that I made some bad assumptions about real world floor-to-floor height of commercial and multifamily buildings. My new calculations put the scale closer to 1:120, I think. BUT this is important: There are no 8-stud wide buildings in the real world that would also have the heights depicted in 10230. This is much too narrow. In other words, use whatever fuzzy scale that works for you in the vertical dimension, and do what looks best for the rest.


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Recommendation on how to build a "brick presence detector"?
I want to build a model of a complex machine with Lego and Arduino or a Raspberry. The machine model also features several accessories that can be added or removed during operation of the machine which influences its behavior. I plan to glue together the accessory bricks. My goal is to detect if that accessory is present on the machine or not.
Are there any standard bricks with contacts built-in, or do I have to make them myself somehow?
(NFC/RFID would also work but the simplest solution will do it)

I'll suggest going the Arduino way and relying on magnetic contact switches - fairly inexpensive, and invisible once embedded in a build.
Another commonly used trick is using an ultrasound distance sensor on the receptacle - the distance will be (near) zero if there's anything attached.

Are there any standard bricks with contacts built-in[?]

Yes - the 9V system which started in the late 80s featured 2x2 plates with conductive metal inserts, e.g. part 5306bc011 "Electric, Wire with Brick 2 x 2 x 2/3 Pair, 11 Studs Long" (besides battery packs, train motors and lights):

Note that:

Each wire is connected to both two studs on the top and two antistuds on the bottom, and
9V-compatible parts are not being manufactured anymore, and therefore are only available in the aftermarket
Any 9V parts in the aftermarket are at least a decade old, and cables are subject to wear&tear.

Since you are not afraid of using glue, and if you're keen on going the "closing an electric circuit" route, you might instead want to use copper foil tape (which should be readily available at crafts stores), or even conductive ink.
Finally, if you want an unconventional approach with contemporary available parts, you can always use Mario pants.

This is where the "Mario pants technique" was invented.  I'm proud to be a witness.  :)

There were also non-train 9V parts with contact bricks.  I have a couple of steady/flashing lights (cleverly, depending which way round you attach them), a siren, and a battery box, plus the bricks. (Late 80s I'd guess).  More recently there are Technic sets with wires that use bricks as plugs.  We have 42095 for example, and I know there are other more complex uses

Worth mentioning that the 9V wires are also very prone to literally falling apart. The majority of wires on bricklink suffer from deteriorating rubber coatings, to the point where slightly bending the wire is enough for the rubber to chip completely off.

I added some of that into the answer. To be fair, OP asked if there are any parts at all, but didn't ask about the reliability of said parts :-D

Thanks for your comprehensive help! I will try to start with foil tape or magnetic switches.

LEGO Dimensions had NFC tags in the round bases, e.g. part 18602c01 "Dimensions Toy Tag 4 x 4 x 2/3, generic":

These can be integrated into the accessories. The tag, and therefore the accessory, can be identified using a 3rd party NFC reader.

If you wanted an entirely Lego based solution, Lego Boost has a colour sensor part 6182145 that can detect colour and is, I think, compatible with the EV3 Mindstorms sets controller as well as the Boost controller. The EV3 apparently also has a colour sensor (and an IR sensor) in the basic kit, but I've not used them. I don't know if any of these are compatible with devices like the Arduino (depends on the connectors I would think), but it looks like a modified ethernet-style port for the I/O. You could potentially daisy-chain a Pi and the mindstorms hub, using the Pi to program the mindstorm.
If you have colour coded accessories, these options could tell you if they are present and which ones are present.


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Error correction after building the D11
I just finished the D11 bulldozer. The last LEGO set I built was 55 years ago, now I got this big machine and I really enjoy it!
But I have troubles with the the calibration and I think the failure is in the gearbox.
What is the best method to reverse engineer the D11 for error correction?
If possible, I don't want to totally rebuild the whole set.

Without any specific details of your issue there is only one option - rebuild the portion that is causing the issue and paying attention to all the details.

I think it is the best way to fix the problem.

If you can tell us more (what actions you took, what did you expect to happen and what happened instead), provide photos or a video of the failure then we might be able to help. Otherwise the most that can be advised is to compare your model to photos or videos found on the internet (hoping you can spot something different) or try to trace the faulty function from either the motor or from the effector end.

How complicated is a rebuild, I’ve got the same problem

The correction was therefore difficult because many parts had to be dismantled to get to the error. The error already happened during the first construction steps.
But many elements can be dismantled as a whole.
In the end, I had some parts left over that I still don't know where they belong.
All this was a satisfying work!

I made a major rebuild of the D11, opened the gearbox, and found this orange Changeover Rotary Catch in a false position on Step 110 (Page 107) of the instructions. After the correction, the D11 runs fine.

Well done! Don't forget to accept your answer if it did indeed solve the original problem :)

Thank you for your recommandation.

Sometimes the calibration failure can be solved by reinstalling the control+ app.


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In the Ferrari 42143 build at Stage 85 should the yellow assembly be loose?
I have gone beyond step 85 but the yellow assembly installed then is still loose, not connected to anything and can be pulled out. I want to make sure this is right as I do not want to go much further and find I have to disassemble and go back. Does it connect later?

I haven't assembled this model, so my answer is based on online building instructions.
Here's the picture of Step 85 you have mentioned. I have added numbers (in lime green) just below connection points I would like to mark on Red L-shaped beam/liftarm and Light Bluish Gray 13L one.

Now if we go back to Step 82 we can see what's is going on behind assembly seen in Step 85. Here, I've marked same points that would be visible behind Light Bluish Gray 13L beam. So assembly in Step 85 goes into "7" connection point and would be inserted into one of two Yellow 2L Technic connectors.

Thank you Alex. I went back and found my mistake - it is now assembled as you have said.

Kind reminder that the best "thank you" is accepting the answer. Remember https://bricks.stackexchange.com/help/someone-answers


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Looking for instructions for this LEGO dragon
I found this guy (or gal) in a lot purchase and was hoping to complete it since it seems there are missing pieces but I can't identify it to find any build instructions that might be available.
Can you identify it for me??

Based on the distinctive "wings", looks like set 70674 - Fire Fang.


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2017 Poly Bag - Blue and Black bricks
I received a bag of Lego bricks without a box or identifying build number. The numbers on the bag are 135149 the year is 2017. The bricks are blue and black. I scanned the QR code and got the following number: 6172058.
I was not able to find any information on your site or even doing a search across many platforms of Lego enthusiasts.

based on

2x PLATE 4X6 in blue
set produced in or after 2017
the other blue parts,
lot of same color parts in 1 bag -> probably classic set with lot of standards bricks

this bag is from
11011: Bricks and Animals

While set is identified correctly, the chosen part doesn't point to the one and only set. Combination of Blue Arch 1 x 6 x 2, which exist in just 3 sets, with other bits in Blue would have been a better choice.

When Joost says "in or after 2017", that's correct because the year (and all the other numbers) on the bag refer to the bag itself. so the bag was designed in 2017, and thus can't be used for sets produced before.

@Henriksupportsthecommunity trouble is that there are 14 sets with 2017-2018 release years alone for this particular element-color combination. And this packaging could be reused for other years moving forward. Thus making a range of possible sets quite large.

@Alex: I know, I just wanted to point out to the OP that there was a good reason for why this answer said "in or after".

@Henriksupportsthecommunity : it's not always as simple as that - just because a set was first released in year X does not mean there can't be production runs of the set in later years. A set first released in 2015 might have a production run in 2017, and thus use bags designed in 2017. That said - this answer identifies the set correctly - no other sets produced at any time match the parts in the bag.


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Why was the monorail system discontinued?
I'm a casual Lego enjoyer and decided to research some old sets and found out about the old monorail system.
My question is why was it discontinued? It was a pretty neat system and I could see something like it working well with modern themes (mostly Lego City), and why was it in so few sets?

Is there a chance the track might bend?

I hear those things are awfully loud.

According to https://forum.brickset.com/discussion/comment/57906/#Comment_57906 :

The reason LEGO has stopped making monorail is threefold,
One, the motors and track molds ran out and would be very expensive to replace.
Two, no monorail set ever made any money, in fact despite trying several different types at high price points they all cost more to produce then they were sold for.
Three, kids these days don't see them as exciting, they are from theme parks or airports, not a futuristic thing at all, in fact pretty boring.

On the subject of molds: according to https://bricknerd.com/home/lego-monorail-bring-it-back-or-build-your-own-7-6-21 ,

The molds and the motor aren’t available anymore because they were produced by a contractor that no longer exists.

See also the question here: What was wrong with monorails?

Changing times is certainly true in lots of cases. When I was a child, I saw vector polygon graphics as the wave of the future in video gaming. Nowadays, they are firmly retro and a sign of the 1980's.

Why didn't they set the price based on the production cost?

@SolomonUcko I would presume that sales would be minimal at a prices so high.


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Is there a Good Replacement M Motor?
I teach robotics with technic parts and M motors. The motors I have bought on Ebay burn out quickly and fit axles poorly (either too tight or too loose). It is difficult to teach when students' motors burn out every 10 minutes!
Please, someone tell me: who sells a good replacement M motor that will last more than a couple of hours of use and fits axles properly?

M motors? Do you mean Power Functions M motors [8883](https://www.bricklink.com/v2/catalog/catalogitem.page?S=8883-1&name=Power Functions M-Motor&category=%5BPower Functions%5D#T=S&O=%7B"iconly":0%7D) or Powered Up Medium motors [88008](https://www.bricklink.com/v2/catalog/catalogitem.page?S=88008-1&name=Medium Linear Motor&category=%5BPower Functions%5D%5BPowered Up%5D#T=S&O=%7B"iconly":0%7D)? And the motors you buy on EBay, are they original LEGO or a clone brand?

For GBC displays at various shows, we usually have to replace a couple of Power Function M motors in a weekend, but that's in a setup where we have a couple of hundred of them running. 10 minutes is very low in comparison. I can't rule out that they could die that quickly if you abuse them in some way, but my first thought was that you can't be using original LEGO to get that experience. To address your other point, in my experience original motors and original axles fit together quite good (I can't see how bad axles could turn into abuse, but I can't rule that out). A

If I understand you question correctly, you are currently using the Power Functions M motors such as this one:

I did a quick search on eBay, and most of the listings I see are not genuine LEGO PF M motors. They are listed as "for LEGO", or LEGO compatible, but they are not original LEGO products. Here's an example of one of the third-party motors:

It looks very similar, but has many subtle differences. The easiest difference to spot is the lack of the word "LEGO" on the studs.
These may be good quality, or they may be significantly worse than LEGO products, but in any case, they were not manufactured by LEGO and did not go through TLGs QA process. These products also likely violate TLG's IP in some way.
The reason that it is difficult to find genuine PF M motors is because the entire PF line has been discontinued and replaced by Control+ in Technic sets. The closest replacement for the PF M motor is what TLG currently calls the Simple Medium Linear Motor:

Unfortunately, this motor is also retired as a standalone product on LEGO.com, although it was included in sets as recently as 2022.
If you are looking to something that you can buy today directly from LEGO.com, the Technic Large Motor is probably the best choice.

Transitioning to the Control+ system would also require purchasing new battery boxes, which are not especially cheap.
One approach is to purchase genuine PF medium motors on a secondary market such as Bricklink. Here's the listing for the PF M motor there. Most established Bricklink sellers take quality very seriously. They know how to identify non-LEGO products and will work hard to make sure you only get genuine parts.

I suspect that high-quality third-party motors would fit the asker's needs better than genuine-Lego Control+ motors.

definitely i have 42140 with 2 motors like this


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Is there a resource (e.g. a website) to identify a lego set based on a selection of parts?
Is there a resource (e.g. a website) to identify a Lego set based on a selection of parts?
For example, I have inherited a big box of Legos including several castle-type pieces. Is there a way to figure out what sets those may gave come from?

BrickLink itself has such a feature - had I known, I would not have written my own a year ago.
Brickit is a new entry in this arena; I haven't used it myself.

Thanks. This is exactly what I'm looking for!


text:
Can you identify these dresses
Can you identify these monochrome slope/dresses? I looked in the curved slope section of bricklink but couldn't find them.

That's the part with item number 36036, called Lower Body, Skirt on bricklink.