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Adrian Hill
08-04-2011, 5:27 AM
When I do engraving I find that if i cut at anything higher than 20mm / sec irrespective of speed I get a mark as the machine jumps off from rest. It seems as if the laser turns on at full power and then accelerates away from rest. Of course the line stats out very deep or thick and then thins out as the head reaches full speed.

I have just thought of a solution that may take a bit of doing, could one not run the machine at the appropriate speed and then turn the laser on and off without having the head come to a dead stop. The machine seems to position, stop, and then launch off into the cut. The problem seems to be that the controller doesn't have an intelligent look-ahead. Maybe it stops because it doesn't know where its going to next. What about using a CNC controller with look-ahead, wouldn't that allow one to process without stopping. I don't mind having to tweak G-Code to do this if it would work.

Any thoughts?
How do you handle this problem other than engraving slowly?

Rodne Gold
08-04-2011, 6:14 AM
Your controller card will or should have different acceration parameters as well as start speeds for all the axes , you can fiddle with that or you can create lead in and lead out points for the cuts. It should also have different types of accleration algorithms that can take aall this into account , if all else failks , consider changing your controller to a more modern configureable one , should cost you less than R3500 *$500* for card , lcd panel etc , all the rest of your stuff will work with a different card..