Engraving a convave

Hey all! I’m trying to figure out how to engrave a concave circle in light burn. Shallow at the top and gets deeper as it goes down. Any tips on how, exactly, to do that?


Heres a picture of what I’m wanting. The line work is a small diagram of what I’m wanting to do.

Hi Josh,

I am assuming you mean that you want to engrave in a material that has a concave shape - like a bowl or a plate?

If so, this It will depend greatly on

  • How long your focal range is on your laser
  • How deep the “bowl” is.

In an ideal world you would split the engrave pattern in 3 parts. And divide each side + bottom of the shape.
This would allow you to reposition the bowel and refocus per part.

To do it all in 1 go, the depth difference must be really small - under 1/2 inch or smaller even. (depends on your Laser)

Yes, i want to make a bowl shape. Im talking very shallow, but a bowl. The material I’m working with is 1.8mm thick microfiber leather. I want it to start off barely marking the material and wind up .7 or .8mm deep. I was thinking some sort of gradient feature in LB would help but if that exists I havent found it

Oh i see what you mean now.

You want to basically 3d Engrave onto the leather.

Grayscale should let you do this, will depend greatly on the material and its color.
Sadly, you will have to sacrifice some bits of material for the laser gods to get your speed/power levels correct.

A normal Gradient might be too linear to achieve what you want
You might need a bit of a ramp gradient:

I would try the above pattern on a 1 inch by 3 inch pattern say - and see the response.

My question is how do i create said pattern? Ive never done it before, lol

If you want to do everything within LightBurn you could use fill boxes with multiple power levels - and use an outline shape as Boolean to cut them into your desired pattern.

I would need to know exactly the pattern you trying to build up to know the best - or rather - one of multiple workflows.

If you want something way more complex, you could use an image generator for gradients than image mask them

Again depends a bit on what you want to do exact

All I want to do is a concave circle. That’s it. figuring out how to do that in lightburn itself is the difficult part. I tried layering circles together but that wont work.

Maybe if you Ramp the Outer Edge?

How do you ramp it? That could possibly work

image

Is there a way to make the ramp in levels with layers? That could very well solve my problem!

You can enable Ramp Outer Edge and then try some values with Ramp-Length,
i.e. your shape has ~50mm width and 10mm flat so test with 20mm Ramp-Length and adjust max power to not cut.

The highest my ramp length goes is 10. That would work if the ramp went further

Your right not tried that length yet, you have to test with 2 circles, increase power a bit and do the outer circle out of focus ( more 2 or 3 mm) then the inner circle in focus. Or you could make the outer circle just 1 pass and the inner 2 passes.
Just an idea you have to test.