Quote Originally Posted by mmurray70 View Post
Im surprised to see all you guys using scales. Seems like a headache to setup and potential things to break with adding scales IMO. Especially Chinese ones. If you have some accuracy problems now why not spend the money on new thrust bearings and rebuilding ballscrews? Just seems so much simpler to me. And a machine without scales can still be very accurate as long as theres no slop in the axis and you have decent encoders. Your hurco should be very accurate with those dmm servos if there are no mechanical problems.
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The machine X&Y is within .0003" mechanically. The Z axis is boxed with a counter weight and is within .0005".
Having feedback from actual slides and not just encoder on servo, will make up for the small amount of mechanical friction/stiction issues. First done this on a bridgeport clone that had steppers ,several years ago. Closing the loop at the table made a big difference for that dovetail machine. Went from machining a 1.0" hole with about .0015" hole roundness to .0005-.0007 roundness, sometimes better, very consistently.

Also i have a old Magnaturn South Bend Lathe that i am retrofitting now, little at a time and would like to find a good linear scale for it also.And after it a Router/Plasma table. To many projects, especially now that i have my own shop that needs to make me money.

Troy