Notches in Rectangles

Whats the easiest way to draw this? For some reason i cant figure out how to take the notches out of the corners.


You can use the ‘Draw Lines’ tool as you have all the measurements defined in this image. :slight_smile:

OK, but if i make a line that is .62" and then rotate it 30*, it is no longer .62" long. Then if i adjust it to .62" long it also changes the angle.

I am not following you. The bounding box will change but the line length should not. Is this not working for you? You can check this doing the following:

Draw a 100mm line, duplicate (Ctrl + D) line and move away from the original. With the new line selected, rotate line by 30°. image

Now select the ‘Draw Lines’ tool and click one end of the rotated line and move the pointer to the opposite line end, paying attention to the bottom of the screen where you will see the length displayed. Here I am drawing over and directly on top of the new rotated line using red. Notice the length display (len: 100.00) which I highlighted in red.


That’s a perfect example of why I can’t just use the line tool. Notice how the one that’s straight goes from 370 to 270, and the one you put at 30* only goes from 370 to 284ish, the line is no longer 100mm long. I mean it is, but it doesn’t travel 100mm once you put the angle on it. Hopefully that makes sense.

And if you look at the original drawing I attached doing it in that fashion would not be correct to the drawing.

The easiest way to do it would be using a CAD package with proper dimensioning. If you’re determined to do it in LightBurn, you could angle the lines, as Rick suggests, then turn those lines into shapes, and subtract the shapes from the rectangle corners.

If you want a line that travels 0.62" horizontally, draw the line at any length, rotate it to 30 degrees, then use the aspect lock tool to set the width to 0.62" while keeping the width/height ratio the same, like this:

Sweet, now new question. How do I turn that single line into a shape that I can use the Boolean functions to delete that corner off the rectangle? I didn’t realize you could turn a line into a shape, which explains why none of the Boolean functions would do what I was trying to do

Just draw more lines from it, then auto-join them. If you use the pen tool, the lines will snap to existing points:




I used red so you could see, but if you make them the same layer color as the original line, then select both shapes and Auto-Join (Alt-J) they’ll turn into a closed shape.

Then subtract that from the rectangle:

Oh duh! You meant complete a shape. I thought there wasaway of making just the line a shape itself but it makes sense it needs to be a closed entity. Thanks for the help sir!

If it was me, I’d do it in Fusion360.

I will look into that program. Is it comparable to inkscape? is it free? does it export directly into a file that LB will open?

Fusion 360 is free for startups generating less than $100K per year in total revenue or wholly non-commercial hobbyist users. There are LOTS of resources available on YouTube to get you up to speed and “sketches” can be saved as .dxf files which can be imported directly into LB.

Wonderful! Thankyou for the info!

Alright so new question regarding fusion, im trying to figure it out now, watching youtube tutorials and what not. But i just thought this is probably the best place to ask a question regarding LB.

If i sketch out an entire part in 3D in fusion, how does LB react to that?

It doesn’t - you’d export the profile of the part as a 2d DXF, and LightBurn will deal with that just fine.

Oz is correct. Most 3d bodies in Fusion start out as sketches. The best thing about CAD programs like Fusion 360 is the ability to build dimensional constraints into your designs. In your earlier drawing, you were trying to draw specific geometry (30° angled lines, various diameter holes specific distances from each other, etc.). These can be pretty easily and accurately set as constraints which can then, as Oz stated, be exported as .dxf and imported into LB. Of course there is a lot more Fusion 360 can do as well.

Alright. So no point in drawing in 3d then. Just the 2d face the engraving will go on. Good to know.

Well, modeling in 3d is pretty handy too - especially with multiple components that are joined together. I also use Fusion 360 for designing parts for my 3d printer. I’d be lost without it.

Of course. I want to learn 3d modeling as well. I was just generalizing if I’m working with my laser and going to be importing into LB there’s no reason to draw it in 3d.

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