I’m attempting to engrave some baseballs. The spherical shape means the focus isn’t consistent across the area and I’m not sure if there’s a good way to compensate for this.
I’m using a Thunder Nova CO2 laser. I do have a Rotoboss that I could use if that would make a difference, but because of the shape I don’t think it would.
Any suggestions?
What focal length lens are you using? I’ve got multiple lenses, and for engraving on non-planar surfaces (or irregular shapes on the rotary), I have a 4" focal length lens set up in a short lens tube.
It’s not magic, and there are tradeoffs, but the long throw and wide depth of usable focus makes it a really useful tool that I go to fairly often.
(Same thing applies with my fiber laser. I have an extra long focal length lens to get more depth of usable focus on irregular objects, like rocks and snail shells.)
Thank you. I do have the 4" lens as well as the 2". I’ll give that one a try and see if it’ll make the difference I’m hoping for.
Make sure you adjust for focal point. The focus point itself should be 1/2 through whatever you’re doing. That allows maximum depth of field (dof) to be useful.
I think I get about 10mm dof from my 4" lens.
Assuming a 74mm diameter regulation baseball and 10mm depth of useful focus, that would mean that the projected area of your usable surface would be a 50mm diameter circle.
Naturally, I don’t have a baseball handy to see how a 50mm/2" diameter engraving would look, but it seems like that ought to do.