I ran the z-torture about 15 times, just looking and watching every part. I ended up adjusting the driver voltage up to .72v, and it seems to be the best results so far. No missed steps on the last job. It still clunks a little when switching directions, but if its losing steps, its catching up. Before it would sometimes miss a big direction jump, of say 5 mm and be completely off.
The stepper barely got warm after doing repeated torture tests. As far as the driver, it did get a bit warmer it seemed- but I wasn’t ever really paying attention to it before. My backlash spring is pretty loose now, the lower nut is hanging out of the nut trap but it didn’t seem to cause any issues. I really just made the lead screw a little bit easier to turn.
Any input on the stepper clunking? It reminds me of the sound of gears not meshing together for a split second. My x and y’s don’t make this noise, but they also spin much slower.