Hey folks - this is driving me to distraction so hopefully someone can help out.
I'm trying to 'photo engrave' a piece of granite. The main issue is that it requires a very shallow cut - say 0.1mm or less. If there's variance of 0.5-1mm over the entire piece there's some obvious problems arising.
There's a few simple - and some quite old - machines that seem to handle this with no problems. Two machines are a GALEKS and GRANITOGRAV - the ones with the angled Z axis. I'm guessing that the angle just makes it a cheaper machine to make as there's no z screw involved.
The Z zero of these machines is set at 1mm. They have a tolerance of 1 to 2 mm in machining depth.
So - two questions I suppose...
1. How do I overcome the tolerance issue?
2. How do the angled Zaxis machine get such good results?
Cheers.
Paolo