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« on: October 25, 2018, 01:45:18 AM »
I ran a series of repeat tests with Bencutlaser. I tested with two different A5 sized machines. I would cut a shape then move the axis random distances. Then home and burn again. These were done at engraving power levels and slow speeds I saw excellent repeatability.
I never powered off the steppers or controller and then ran the test again. A dial indicator would be better than just a visual compare. I think that as you switch modes you might introduce "creep". If it stops between poles it will probably stay. If is at a peak between poles from micro-stepping I think it will have to fall forward or back. If it doesn't fall consistently it will creep. With a dial Indicator you will be able to see if it is staying in place or moving after power drops.
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When I installed homing switches I took some time picking the switches. I bought a bag of 20. I then tested each switch for its "feel", travel, overtravel and it's sound. Some had a real crisp click to them and the click sounded like a glass breaking. Some were just plain mushy and traveled a bit they broke over, their audible click was not crisp and clear, closer to a crunch.
All of the switches that did not feel clean had a lot of travel, traveled more than half way before they broke over. They also had a lot of over travel. The crisp switches all broke earlier and had little to no overtravel at all.
A couple times I continued these burns until the shape fell free from the board. I noticed no stepping in the cut edges. Of course that could have been the edges were burned away. But I should have seen a coning effect or something other than the straight up and down sides I saw.
So the quality of the switches has a lot to do with it and then you pick the best. Another help is slowing the "homing feed" to about 350. Homing seek was about 5000.