75

This image shows the dimensions in LEGO Units. 1 Lego Unit is 1.6mm (the thickness of the plastic wall). In those units the stud's diameter is 3 (= 4.8mm).


42

All Aboard! I'd like to add my all-time favorite LEGO piece: x870cc02, THE BLACK WHISTLE! The white brick is a microphone. Attach it to your train's motor and BLOW THAT WHISTLE! Depending on how short (or LONG!) your whistling was, the train would go forwards or backwards. Real-world use: Not only did it drive your train round the bend, but your ...


39

This image from Brickipedia should sum it up nicely: A plate is exactly one third of a brick in height (3.2 mm as in the diagram). In other words, 3 plates stack to match the height of a brick. This is useful to know if you're short on a certain size of brick, but have enough plates of the same shape and color to cover it in height.


35

The "Extra Large" grey baseplate is 15"/38cm square, with 48 studs to a side. Alternatively, the moulded castle baseplate had a greater volume (with hight), and a base size of 32x48 studs and 6 bricks high (15"x10"/38x25cm) (in other colours as well): Tim offered up the following, also with a base size of 32x48 studs, 6 bricks high (15"x10"/38x25cm) (it ...


34

I definitely know them as the headlight brick, and they look like this: HoMa's world of bricks has a nice page dedicated to this brick! http://www.holgermatthes.de/bricks/en/lampenstein.php LEGO's Pick a Brick lists this as an "Angular Brick 1x1", Design ID 4070 (equivalent to the piece/part id).


33

I did the unthinkable! ...I had to know. I opened one of my two weighted bricks. One of the two ends has a glued on cap that I've cut around using an utility knife. The piece of metal it contains fit almost perfectly in the cavity. I don't know metals but it has a rainbowish kind of sheen to it. Here's a close up: I'm now gluing it back with super ...


32

Check for visible part numbers This usually only works if you have the physical part in front of you. Look for a 4 or 5 digit part ID on the element. These are usually printed on the inside. A magnifying glass and good lighting can be helpful. Many bricks will also have other numbers printed on them, but only the 4 or 5 digit numbers are useful for ...


27

Ø is a pretty standard notation for diameter. So w/Ø 3.2 Shaft means the item has a shaft that has a 3.2(mm) diameter.


24

Usually, the LEGO group doesn't seem to have much organisation, at least in the past. That's why you can find sets with two different numbers, or two different sets with the same number. Now the keyword here is seem, as I suppose there was some logic to it even in the past. But nowadays there is some logic, and even if not all of it is understandable, you ...


23

From principles of molding, you want a uniform part thickness throughout if possible. This facilitates plastic flow as well as dimensional stability (you want uniform shrinkage on cooling.) Removing a divot from the underside of a stud serves this purpose in a regular brick. The Technic brick with through holes would have had a large amount of solid ...


23

One of the smallest pieces is the detachable handle on the 1 stud gear shift element. The black part in this complete lever:


21

The ridge is there to make the base the standard 5LUs wide (see also "What is an Erling Brick"), enabling it to accept the standard stud. I believe the rest of the brick was thinned out so that the combined "depth" of the Erling brick and a 1x1 plate (its common usage as a headlight) was the same height as a standard brick. From the HoMa's World of Bricks ...


21

The screwdriver is also very small, but I'm not sure it beats the lever handle. Also, one could argue it has to be detached from the tools wheel first. But if you buy second-hand lots, there's a good chance it would be detached, and it would easily escape through small holes. Similarly, the various plumes aren't very large either:


21

The studless have SEVERAL advantages over the studded design especially when you want to include moving parts. Just the clearances between connections is important. Sariel sums it up in his book well. He says there are advantages to both systems (stud-full, for example, are more rigid) but the fact that the stud-less look more realistic and, of course, the ...


20

The Erling Brick: named by the LEGO Designer Erling Dideriksen, who invented this element in 1979.


20

In the 60s, Lego did produce a separate system for architectural modelling called Modulex which used a 1:1 ratio 5mm cube as its basic brick. It wasn't successful and was discontinued in the late 60s. I believe the 6:5 was chosen so that studs could fit into the geometry. Related: why the plate is 1/3 of the brick's height. By adding two plates to the ...


20

In most cases you can find the weight of a brick from Bricklink an unofficial LEGO site that takes weight measurements from user submitted data. Bricklink states the 1x4 brick as 1.64 grams in weight. LEGO bricks tend to be odd weights because the design process primarily focusses on the physical aspect. A 1x8 and 2x4 brick both have exactly eight studs, ...


19

As said, this is the point where the injection happens, usually known as a gate. Sometimes, LEGO tries to have in a non-visible place, but the process of moulding is extremely complicated and forces specific requirements on the gate placement which mean it's sometimes impossible to hide it. The basic rule of thumb is that the gate is usually near the center ...


19

These pieces are frequently used for decoration now, but they were originally used for sliding doors, particularly on train sets. Here's one of the first uses from set 7838 in 1983: While they could be used in structures, these were frequently used for putting doors on the train cars themselves: These parts can also be used to create tracks for other ...


19

The holes in Lego Technic work very well as holes. By which I mean, I have built very successful motor-driven cross slides for small machine tools using Technic pieces. When paired with nominally 4.8mm metric ground rod (which tends to have a negative tolerance) the 4.8mm holes are a nice sliding fit. Imperial 3/16" rod at about 4.76mm also works, but is ...


18

I had guessed that smallest piece I have owned is one of these (image courtesy peeron): It really is stupidly small (so small that I've lost the only example that I possessed). However, I have since discovered that the lever weighs less, and that the screwdriver will fit through smaller holes. Update: I've recently come across some of these: It's an ...


17

I believe the main reason is so that the pieces are easy to identify in the instructions - as many LEGO sets don't have the Technic style "List of elements used in this step" it's always a fun game of "Spot the difference" to see what's changed: If those pieces were all red, then the target audience (5+ on those sets for example) might find it very ...


16

These aren't defects, they're a scar from the moulding process, it marks where the plastic was pumped into the brick. It's more noticeable on some bricks more then others, every brick manufactured this same way should have a similar mark.


16

One obvious answer is all components of the power functions family. Lights can be used as lights, motors can be used as motors.


15

This is likely a hold-over from when these were used primarily as roof pieces, and the texture provided some realism to the house/building sets.


15

The regular connector have simple angles which are multiples of 22.5°. #4 is 45°, #3 is 22.5° and #5 is 67.5°. That's pretty boring stuff, but there you go. The 53.5 angle isn't as bizarre as you would think and there's a very good reason for it (and less boring to me, but YMMV). That reason is that it forms a Pythagorean triangle, and specifically the ...


15

It's difficult to tell exactly what part this fragment came from, but it looks like it is part of a broken Technic gear or pulley. It looks like it probably came from 3736: Your fragment looks like it was probably once one half of the center axle hole of that part. In terms of repair, I suppose you could try to glue this back together, but given that the ...


14

Most 1×2 (and longer) plates and bricks have a pin at the bottom right in the middle of studs that perfectly fits this hole. Connecting this way gives you half-stud shift.


14

In my opinion, you don't need to look further than plastic quantity, and thus cost. Take a normal brick or plate (easier) and look inside it. You'll notice that each stud is hollow, but from below. Why? Simply because there's no need to have it full with material as it serves no purpose. It's easy to make the mould that way, it doesn't remove any ...


14

While LEGO uses metric nowadays, you may be interested to know that the bricks they originally copied (and bought the patent for later on) were made in the UK and thus probably used imperial measurements (although dimensions are not specified in the original patent). You may want to search for UK patent 529580 or Kiddicraft to learn more about this. There ...


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