Hello, everyone. I’m dealing with a case where I need to engrave on a slightly rounded object. Don’t want to mess it up right away, so I’d better ask if any of you have dealt with this. My point is that the focus is different on the edges than in the center. It is a flask, see photo.
I would use a 3" or 4" lens for the job and focus to half curvature. But I will also do some tests on thin plywood which I will bend to the same shape as the bottle.
Thank you, Bernd, for your advice. Just if I understand correctly. Should I replace the lens in the machine with another one? and then focus about halfway through the curvature? I’ll try that on plywood as well eventually.
yes if you have a 3" or 4" lens I would prefer them. The focal length is longer. But, if you don’t have lenses other than your standard lens, you can also give it a chance.
It is easy to fix plywood in the radius of your bottle, this is to see if the engraving will be even and fine enough when you focus to the center of the curve. I think it will probably succeed.
A 2" lens has a depth of field (focus) of ~1.9mm, so it depends on your curve.
You are not trying to directly mark stainless are you?
You need some type of coating to make this work properly. I use LBT100 for my co2 machine…
Make sure to secure the flask… they have a tendency to rock a bit or move when the machine runs…
Thank you, no, that was just a demonstration, of course I use paint. I use OMTECH black engraving powder. So I need to get preferably a 3" or 4" lens, then try it with half square on plywood and then only go to steel.