Quote Originally Posted by kd7eir View Post
I was considering the same thing until I read Printbus's rationale for not doing it. Thank you for saving me a considerable sum of money. Heck, for the price of one lead screw I can buy several M5 rods to have at hand in case one of them becomes suspect.
Well, I'm still interested in seeing if a different opinion comes up from someone who has actually done the retrofit. I could still reconsider doing it if the rationale is there and the mechanical aspects are reasonable. Before I understood all the details, I had picked out some lead screws and was very close to ordering them. It turns out they were four-start screws (four separate threads are cut into the screws) with a lead of 8mm per revolution. Between the torque issue and the backlash issue, my guess is I would have regretted purchasing them.

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adamflip, AbuMaia is correct on the microstepping detail. On RAMPS, jumpers set the level of microstepping. I believe RUMBA also uses jumpers. With RAMBO this is set from firmware. A related aspect to be aware of is that the torque available from the motors drops off as you increase the microstepping. In other words, a motor driven with full steps (200 steps per rev) will have more torque than one driven with 1/16 microsteps (3200 steps per rev), but at a cost in Z axis resolution. Just another detail in the potential can of worms that could be opened here.