Help - Current For Stepper Motor Driver AM882 - ProTuner

[PaulP]

Cheers for the info Kitwn,

The boot is defo causing the shift, it's repeatedly working fine on this part without it and on other parts without it but with it on it was squashed right down and catching edges, plus if my steppers are 'under amped' by 50% it wouldn't surprise me to fail in the same 2 spots. It'll be easier to re-tune (up the amps) the steppers than it will be to make a new bristle skirt, but only if it's the under-amped issue causing the problem. The boot assembly weighs about 400g so no real weight on the system.

My main concern before looking into the bristle issue is the amps being fed to the steppers. I sense they are too low, it's a dual screw axis on X and a single on the Y both use 5mm pitch screws. Before I changed the "PeakCur(A)" value in ProTuner from 4A to 2A it could do 5mm cuts with a 1/4in 2 fluted cutter, now it struggles and sometimes triggers the stall/estop when doing 3mm passes in Trespa (HPL).

The problem was that the motors were getting almost too hot to touch and I wasn't sure if the PeakCur(A) was too high and would burn the motors out. So I lowered it a while back to 2A but now I noticed some missed steps I'm wondering if it should be set to the 2.1A or the 4.2A.

I get that the currents are always specified per phase on motor specs but what about in ProTuner? Does ProTuner's "PeakCur(A)" refer to the current for each phase or to an individual phase?

Currently I'm set on 2A but am wondering if I should really have set the value in ProTuner to 4.2A, or at least to somewhere closer to 4.2A like 3.8A.

Just for the record I'm running all stepper in series configurations, ie 4 wires.

I'll include some pics of the fusion 360 model for sizing and scale but it's a small 2 part dust boot with about a 4-5mm thick layer of bristles glued into a channel on the underside. The drawings won't show the bristles in situ but it's too cold and late for me to go in and take a pic of the actual dust boot at the minute.