Extruder stepper makes buzzing noise on my I3

Hi,

During some prints, my extruder motor makes a subtle buzzing noise that you can hear on the video:

[www.youtube.com]

Now the noise is amplified a lot on the recording. It's not really that loud, but it's audible from 1.5 meters when the room is quite.

I'm using Ramps 1.4 with A4988 drivers. The stepper's I max is 1.2 set the vref to 0.8.

The noise only occurs during printing when the stepper is rotating at printing speed. The noise doesn't occur if I manually extrude or retract filament at higher speeds.

Lowering the vref does reduce the noise, but it doesn't get rid of it. given the formula vref = I_max*8*0.1, the max vref is 0.96V, so I'm well below the max already with 0.8V.

Do you guys now what could be causing this issue? It's a bit annoying, but if it can't hurt, than I'm fine with it.

That is an odd noise, it sounds like an electrical arc but then if it was smoke and the smell of ozone would be surrounding your printer.

To say you are well below the max at 0.8v is perhaps not necessarily true. To prevent motors heating up you don't want to run them at more than 75-80% of their max current and often you don't need to be anywhere near this level to avoid skipped steps. Try running at a much lower vref, but try a few prints to test that the motors do not skip. Try moving the axis progressively faster and faster and see the point at which it stalls, if this is fast enough you're all set. Also you can check if its the drivers or motors by swapping them from one motor to another to see if it changes.

Edited 1 time(s). Last edit at 04/29/2017 05:30PM by DjDemonD.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions