z-axis limit is shielded and bonded.  all others are well away from any other wiring.

In motor tuning with acceleration at 10 what velocity do your motors stall at ? (what is the maximum speed you can achieve ?)

Tweakie.

max speed is set at 250 on x and y.  It will go up to 350 with no problem.

I think you have to be extremely logical in your approach to this problem if you are going to solve it. Change just one thing at a time.

Try what Russ suggested:-
Drop your velocity to 120 on the X and Y then reset your kernel speed to 35kHz.
Carry out as much testing as is necessary to establish if you still have lost steps at these settings.

Tweakie.

I have found that when a stepper gets "HOT" and not within an operating temperature they will
start to behave weird. A wrong amp setting and they will get hot quickly. If you are going to be running long programs then you should experiment
with velocities and acceleration settings to see what will work for what your doing. They get hot because they are doing "work".

RICH

My Chinese CNC router has hot steppers, you couldn't touch them. Runs 90 volts, rapids very fast, a DSP control runs it all. I solved the overheat problems with a watercooling jacket on them gantry ones, pic attached.

where did you procure the water jackets?  It seems to be a good stop-gap solution.  I had been thinking about putting aluminum fins on the motors but the water jacket would be much more efficient.

I fabricated them myself, just .063" sheet aluminium shells welded together. The router has a watercooled spindle anyway so I just plumbed lines to the Y axis jackets from the pump.