Rebuilding terribly engineered laser cutter

[threedee]

This image says a lot...



It's unclear from some of the other pictures, but this one is particularly interesting as it would appear to show the distortion on spokes projecting radially from the spiral centre, and at a position where the Y axis velocity is tending to zero or accelerating from zero. Is this true of other images? (they are less clear).

Could this be related to torsional elasticity of the couplings/Ali extension bars on the Y-axis?, is it worth trying to drive the two belts separately with two steppers, and removing the length of Ali bar?

Just a random thought

This particular picture needs rotated 90 degrees. The "spokes" radiate in X direction (horizontal).
ALL spiral cuts at ANY speed exhibit this same pattern. Lower the speed, closer the oscillations, making even through cuts difficult in those places due to increase in speed due to vibration. When on cutting speeds (10-20mmps) either kerf gets too wide (by increasing power beyond required for cutting) or not cutting through (power is set exactly right for cut through).

I have replaced aluminium spiral couplers to spider couplers to no effect. The shaft that drives Y is 8mm bars, cant be that much windup in them.

Also, the "spoke" pattern changes angle on changing speeds, but is always there and always radiate in spirals/circles. It makes a strong case for resonance vibration somewhere, i'm convinced that its the Y rail bolted into case. Being only 12mm and 750mm long it can act as an amplifier for vibration from motors... Hence me replacing Y.

Yes ours at work also has a very nice rounded case and a small stand:)
Obviously they would come out for repairs/maintenance but it's going to cost heaps!!

Cost whom ? You or them ? If its you - whats the point for that 35k price :D