Fight VFA
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Dear ladies and gentlemen,
i am fighting VFAs since years now with my printer - changed every bit but never completely erased them.
While this topic is now getting more attention everywhere, also within hardware resellers and manufacturers (LDO, PRIORIFI, ...) i wanted to highlight some settings from a user who uses klipper:
link
So this is what i always thought but never be capable (time and technical understanding) to really proof but in my opinion this is mostly it! Nema in combination with TMCs.
Ofcourse there can be many other mechanical issues be in parallel but maybe somebode here can now help to translate this settings into a M569 command who is better in this.I can hardly interprete here everything but maybe it is worth a try! Also when I think of the many unsolved VFA threads in here...
Regards
facet -
That's interesting. Have you seen this?
https://docs.duet3d.com/en/User_manual/Connecting_hardware/Motors_tuning
Only the Duet3 mini and toolboard are using 2209 chips, so I'm not sure how well the values from that page would translate to the other driver chips used on Duets.
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@phaedrux Hi, thanks for the quick reply. Ah yes ofcourse this are two different types of drivers - but I thought maybe there is a way that somebody who is really in this topic can adapt this regardingly or find out what setting combination especially makes the difference (independent which 22X driver model) ?!
I thought it's worth a try...
Regards
facet -
@facet
There are special stepper motors that minimize this effect.
See this YouTube Video. -
undefined droftarts referenced this topic
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@facet I'm going to have a look at this issue and try and suggest some settings for you to test.
It seems VFAs may be caused by the default TMC2209 settings, possibly coupled with motors that are either relatively poorly designed/constructed or have a mid-band resonance that is right on the frequency you want to print at. I will look at the various stepper driver settings, and convert them into RRF settings.
Let me look into it, and I'll get back to you.
Ian
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@droftarts Wow that sounds great!
But to get me right: i have a duet wifi! But the VFA i had also with RAMPS & TMC2208, 2130 and 2100 before i tried out the duet (and stayed
)So i think, the tuning can be somehow a general topic for TMC / NEMA17. But I really would try out the mentioned settings if applicable within the duet firmware setting commands - maybe some bindings are not existing here until now?!
If you could point out which ones are making the difference in your opinion, some ranges can be tested by ourself then. If there are not too many different variables and combinations ofcourse
Regards
facet -
@facet there are other causes of VFAs, and it depends how far down the rabbit hole you want to go. The finger has been pointed at mismatched pulley/belts, notchy/dragging/wobbly bearings, dual-gear extruders, various motors, and now stepper drivers. Generally, I haven't heard many complaints about the TMC2660s on the Duet 2, and that you have obviously been through quite a number of other drivers, so I'd probably recommend you look at other sources for the VFAs first. There's various test prints you can do to help narrow down what may be the cause.
I'm looking at the TMC2209s first, and see if there's anything specific we can point at as being a beneficial change, before looking at the stepper drivers on other Duet boards.
Ian
Cartesian bed-slinger with Duet 3 Mini 5+ WiFi and 1LC : RRP Fisher Delta v1 with Duet 2 Maestro : TronXY X5S with Duet 3 MB6HC and Roto toolboard
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@droftarts you are right ofcourse - but like I say'd I changed already every little bit of the printer and nothing had so much effect to get rid of it. Mostly VFA will come from mechanical issues, but if there is nothing anymore to optimize this will lead to TMC and NEMA.
I guess the people out there get now more and more aware of how to correctly setup their printers while this VFA discussion is getting more popular everywhere.
I spent now 2 years to exchange everything on my printer, genuine GATES pulleys and belt, EZO Japan bearings, CPC / HIWIN Rails, total square aluminium topplate cnc milled and drilled where the rails are mounted, and new electronics.
Tried different extruders (dual gear and single) and also had a look at vibrations from hotend-fan or BTLs.So i guess I am really at the end here what you are recommending and want to got as deep as possible into that rabbit hole now.
If the PRIORIFI Nema would not be so expensive in comparsion how the marketing is... but maybe there will be more and better experience reports soon.Really appreciate your effort here.
Regards
facet -
@droftarts Hi! I just wanted to ask nicely if there are any new results or thoughts on this optimizations?!
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@facet most of the VFA comes from non geared BMG gears. (used on the prusa mk3)
They also get less visible when printing over 60mm/s
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New year - old challenge
Happy new year!
Are there any new insights on anyone at this topic?I also saw the first YT videos where the BAMBULAB printers have VFAs...
Regards,
facet -
I'm also very interested in this topic.
My Maestro and its TMC2224 drivers, with these 0.9* steppers (https://www.omc-stepperonline.com/nema-17-bipolar-0-9deg-46ncm-65-1oz-in-2a-2-9v-42x42x48mm-4-wires-17hm19-2004s) produce quite a bit of VFA.
Obviously tuning the drivers to reduce this would be amazing. But, I'm open to new motors as well. There seem to be quite a few cases where a motor swap nearly eliminates VFAs. Now the new Prusa MK4 is advertised as having "VFA free motors".
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@CCS86 unfortunatelly I don't have any upgrade on this topic - maybe the colleague was able to figure out some settings meanwhile...
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Man, it would be great to put our heads together and test our way to better quality.
