How do you make specific angles for triangles, trapezoids, etc?

I was asked to make a triangle wallet that was basically 4 equilateral triangles that fold onto one another. After attempting to figure out how to get precise angles to make each corner 60 degrees I ended up just copy and pasting an image of a triangle from a Google search and then tracing it and then drawing with the line tool from point to point of the traced one(traced objects never have perfectly straight lines) Is there a way to create exact angles? The only thing I noticed was the indicator at the bottom that reads the current angle but it changes if you rotate the item and it goes away once you place the line.

I use the create polygon tool. Then I go to shape properties. I then select how many sides I want.

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So you can select how many sides but not the angle of each? I’m asking about making specific angles.

For regular polygons, those are dependent.

In a regular polygon with n sides:

Interior Angle = (n - 2) × (180 / n)

  • Triangle = 60 = (3 - 2) × (180 / 3)
  • Square = 90 = (4 - 2) × (180 / 4)
  • … and so on

For irregular polygons, the angles are whatever you get based on the layout you want.

To generate a line at an arbitrary angle, draw a horizontal line (parallel to the X axis) of the desired length, use the Numeric Edits toolbar to rotate it as needed, then drag-and-snap it into place on the polygon you’re creating.

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I suggest you to use some free CAD (there are a few), make a sketch of the triangle and set the angles and lenghts as you wish. You can the export the shape as a DXF file into LB or produce a drawing of it and export as svg to LB.
LB does not have the possibility to measure angles.

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This would’ve worked for this specific project where I needed the equilateral triangle but I was wondering about an angle tool

This is pretty much what I expected, but I wanted to make sure I wasn’t missing something. Thank you!

Thanks. This seems like a more complicated process than inputting the angles on a shape generator/calculator. I will still give it a try though

If you knew the degrees you could use the circle array then connect the intersections with the pen tool.


One way is to draw a line, set the length, go to edit nodes press L to make sure its straight, press A to align horizontally. Then exit out of node edit and set your angle, duplicate and mirror. Use alt to help you connect the three sides.

I was thinking the same. I’d probably suggest something parametric such as FreeCAD or Fusion rather than ‘dumb’ CAD. For simple 2D parametric sketching I think FreeCAD would be simpler to get up and running with as it doesn’t require an account to be set up (unlike Fusion).

FreeCAD sketch:

FreeCAD sketch exported as DXF then imported into LightBurn

Hope this helps.

The “make a line, duplicate it, then rotate the duplicate” method is likely the easiest method to make arbitrary angles directly in the LightBurn UI, but you know the classic trope of a student asking their teacher, “When will I ever use this?” Well, if you ever asked that about sines and cosines, we found the answer! :smiley:

Trig

I still use the three trig functions extensively when I’m designing things. Being able to quickly math out a number using sin/cos/tan and right triangles is a really great skill to have, although with the tools we have available, you don’t need to know how to throw algebra around to make things.

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Great for those of you that didn’t fail algebra and hence couldn’t even go on to geometry.

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