631
General Mach Discussion / Re: Calibrating each axis?
« on: May 07, 2008, 09:51:15 AM »
Yes - you have calculated your steps per inch correctly - that does NOT now need fine tuning. What you need to do is TURN OFF backlash compensation. Move to the right.Stop. Set up your DTI on zero. Move 1 inch to the right on an MDI command (to ensure that Mach 3 puts out the correct number of pulses). Move BACK one inch on an MDI command.
In theory your DTI should read 0 - but I don't think it will. Whatever your DTI reads is the backlash you have in your system.
Enter this in the backlash and switch it back on.
Do not expect Mach3 to apply backlash so you don't notice it. It starts, stops, starts again, stops and then finally gets going. You are quite right, you can adjust the speed at which it does it, but I wouldn't put it up too fast - maybe 50% if your top speed is not too fast. It does not matter in the scheme of things - what you are after is accuracy - not a ballet. Backlash is accurate - mine is about 56 thou - (I,m working on it - maybe these super dooper ball screws are called for) - and in the end my system gets there. I did some ball shapes on a rod the other day (in brass) and you couldn't see the join.
In theory your DTI should read 0 - but I don't think it will. Whatever your DTI reads is the backlash you have in your system.
Enter this in the backlash and switch it back on.
Do not expect Mach3 to apply backlash so you don't notice it. It starts, stops, starts again, stops and then finally gets going. You are quite right, you can adjust the speed at which it does it, but I wouldn't put it up too fast - maybe 50% if your top speed is not too fast. It does not matter in the scheme of things - what you are after is accuracy - not a ballet. Backlash is accurate - mine is about 56 thou - (I,m working on it - maybe these super dooper ball screws are called for) - and in the end my system gets there. I did some ball shapes on a rod the other day (in brass) and you couldn't see the join.