Hi All,

Long time builder first, time poster here with a bit of a technical question regarding construction minifig scale buildings. I wish to build a triangle shaped modular scale or 48x48 sized building but have been stumped with figuring out the brick geometry using LDD and actual bricks have failed to give me a consistently straight equilateral or isosceles type triangle shape. The only building I know was from https://www.youtube.com/watch?v=on2CzSVTJxc from Jangbricks on Youtube.

For reference of my Lego CV

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Any thoughts or remarks about triangular buildings would be greatly appreciated.

 

Thanks, Berl

 

 

Hi Berl, welcome to eurobricks!

Your best bet is to consider triangles called Pythagorean triples - special triangles where all three sides are a whole number, e.g. a 3-4-5 triangle (with angle of 90, 36.87 and 53.13 degrees).

For example, below are two methods of building a 3-4-5 triangle "off grid":

On the left, studs are placed on the corners of a 4x5 rectangle, and a 6 stud beam sits across them.  This is because the corners of the 3-4-5 triangle lie in the centre of a stud, so you count the gaps between studs.

On the right is an alternate build using hinge plates.  The pivot of the hinge is in the corner of a stud, so this time you count the number of studs. A second hinge completes the right angled triangle and puts the studs back "on grid". 

Mirroring these right angle triangles will give you an isosceles-triangle shaped building.  The triangles can be made as big as you like, just keep the blue tile side length a multiple of 5.   I don't think an equilateral triangle is possible, but there might be a way to make something approximately correct. Maybe you could use the Nexagon hexagonal plate as a starting point (e.g. look at the Lego Star Wars Freemaker Adventures set "Tracker 1")

Hope this helps!

 

 

Edited May 19, 20186 yr by NathanR

This looks almost promising but it looks like it would have trouble scaling to be 20-48 studs wide, especially if the piece you mean was https://brickset.com/parts/6173203/rotor-w-4-85-hole-no-1 ? The example in the video seems much to large to have been built with something like this perhaps? Is there a common combination of plates and hinge pieces?

 

 

You need lots of wedge plates on all three sides to pull it off. Here's one that I did many years ago using wedge plates on opposite sites.
AC

 

There's a lot of options. Pythagorean triples have already been mentioned. But as it sounds like you're also aiming for something the size of Jangs, it becomes pretty easy. Size is your friend, the flex, and space of the brick will help accomodate things, and you don't nescessarily have to attach it to the base (instead using tiles and terrain features to just 'slot' it in)

Worth saying that Jang's example uses a 45degree angle for the third side, And that won't work with LEGO dimensions, not strictly anyway. Again, size gives you wriggle room with the gaps, and he's used hinges to connect that third corner, so very easy to hide a small gap, (like I said, size is your friend) you'll get just enough 'give' to make it work. use hinges on the right angle corner, and you end up with what he has.

Alternatively, Clips and bars will help you keep things straight and can likewise be used to hide connecting gaps (A few official sets have used that technique now) But yeah, with straight sides and big, it's super easy.

Hmm. I appreciate the feedback. I was playing around with this in LDD yesterday and the only thing that worked was using a 4x4 wedge plate with a notch in one end to get a straightish line. But those pieces got discontinued in 2004.

Use pythagorean triples with a calculator; i.e., tan^-1(opp/adj). Add or subtract 0, 90, or 180 (if necessary), then type in as many digits as the calculator displays for precision.  With a bit of patience, you can design any shape imaginable in LDD.