silent stepper (tmc2100) upgrade - need to change acceleration?

[greengecko 8]

i just upgraded my UMO with silent steppers and initially it was great. then i noticed that one axis was missing steps. as much as i tried to dial in the steppers by adjusting the current by fixing the Vref (0.8 - 1.2V) i could not find a setting the worked for longer prints. also played with the cooling  fans as the steppers get quite hot regardless of the passive cooling. the only way to get a longer print (>2 hours) without missing steps was by adjusting max acceleration Amaxx and Amaxy with the ulticontroller.

here is my question: am i the only one who has missing steps or do most of you reduce the acceleration or any other tweak?

if someone of you has any advice on such settings or another idea what could be wrong with my silent steppers please let me know. i changed vmaxx and y from 9000 to around 1500-2000 so quite a bit and it obviously slowed down the overall print speed but no more skipping of the steps.

thanks in advance

Edited August 3, 2017 by Guest

[greengecko 8]

i solved my issue with the silent steppers.

. They are indeed great and i can only recommend them. my printer is so quiet i sometimes scared that i cannot hear it when i enter the print room.

the problem i had was solely due to my cooling. to reduce noise further i also replaced the electronic fan by this design https://www.youmagine.com/designs/ultimaker-electronics-fan-replacement

and this does not provide enough cooling for the silent steppers. as an intermediate solution i just positioned the two 40 mm fans next to the xy steppers using tape.

works now like a charm. i still kept reducing amaxx and amaxy to 5000 as otherwise i still loose steps i

when increasing speed to around 90mm. so all good now and for everyone i can recommend that upgrade. feels like a new printer.

Edited August 4, 2017 by Guest