Notifications
Clear all

VFA Artifacts on X+Y Straight Edges  

Page 51 / 62
  RSS
gb160
(@gb160)
Estimable Member
RE:

Anyone tried the updated  belt tuning guide ? The web app now has the waterfall plot which will hopefully make tuning it easier, and the tuning instructions have now completely changed, target frequencies are higher, although that might be related to the new position of the extruder when tuning.

Any effect on VFAs?

 

https://belt.connect.prusa3d.com/

Posted : 17/07/2025 10:25 pm
Jondoe
(@jondoe)
Eminent Member
RE: VFA Artifacts on X+Y Straight Edges

Smooth idlers are definitely a problem if they are undersized - as I mentioned earlier I sanded the teeth off the belt on my AD5m where they run over the smooth idlers and it got rid of all the belt ripple on pure x moves. 

Posted by: @malpan

I suspect they won't be an issue since the EPDM of the gates belts deforms onto them and from the literature smooth idlers don't seem to add much energy, imprecise toothed idlers can be far worse. That does however make me wonder about how much smooth idlers will deform the belt teeth over time and lead to engagement issues, so maybe a stiff self lubricating elastomer idler will improve service life.

That's really impressive.  So if the frequency-dependence has gone, that suggests you've solved the resonance problem through damping, and now it's just a mechanical/meshing issue.  But your compliant idler runs on the smooth side of the belt.  So apart from the meshing compliance that you're tackling with the elastomer pulley, is it possible that the two idlers that run on the toothed side of the belt are now having an effect?

 

 

Posted : 17/07/2025 11:00 pm
Lucas Restrepo Henao
(@lucas-restrepo-henao)
Active Member
RE: VFA Artifacts on X+Y Straight Edges

Posted : 17/07/2025 11:09 pm
Lucas Restrepo Henao
(@lucas-restrepo-henao)
Active Member
RE: VFA Artifacts on X+Y Straight Edges

Posted : 17/07/2025 11:12 pm
GBMaryland
(@gbmaryland)
Estimable Member
RE: VFA Artifacts on X+Y Straight Edges

 

Posted by: @gb160

Anyone tried the updated  belt tuning guide ? The web app now has the waterfall plot which will hopefully make tuning it easier, and the tuning instructions have now completely changed, target frequencies are higher, although that might be related to the new position of the extruder when tuning.

Any effect on VFAs?

 

https://belt.connect.prusa3d.com/

I just tried the webapp and it worked a lot better than the mobile app. The procedure seemed to be different that the prior one, in so far as which part of the belts you strummed?  It was not obviously clear.  

I'm printing the Robo Alpaka now to see what things look like (after reinstalling my HF .4).

Posted : 18/07/2025 12:43 am
Rainer
(@rainer-2)
Honorable Member
RE: VFA Artifacts on X+Y Straight Edges

Have you compared it with the previous configuration?

Did you have to change the voltage compared to the original version?

Posted by: @gbmaryland

 

Posted by: @gb160

Anyone tried the updated  belt tuning guide ? The web app now has the waterfall plot which will hopefully make tuning it easier, and the tuning instructions have now completely changed, target frequencies are higher, although that might be related to the new position of the extruder when tuning.

Any effect on VFAs?

 

https://belt.connect.prusa3d.com/

I just tried the webapp and it worked a lot better than the mobile app. The procedure seemed to be different that the prior one, in so far as which part of the belts you strummed?  It was not obviously clear.  

I'm printing the Robo Alpaka now to see what things look like (after reinstalling my HF .4).

 

Posted : 18/07/2025 1:13 am
Jürgen
(@jurgen-7)
Noble Member
RE: VFA Artifacts on X+Y Straight Edges
Posted by: @rainer-2

Did you have to change the voltage compared to the original version?

That's probably a translation error -- you mean "change the tension", right? Both terms translate into "Spannung" in German, but in English they are different for the mechanical vs. electrical domain. 

Posted : 18/07/2025 5:03 am
2 people liked
Chris Hill
(@chris-hill)
Honorable Member
RE: VFA Artifacts on X+Y Straight Edges

That’s interesting - English still uses ‘tension’ for ‘voltage’ in some specific cases, e.g. HT leads (high tension) in a car engine’s ignition circuit, but it’s not common enough for me to have quickly made the link in Rainer’s post. 
/off-topic

Posted : 18/07/2025 5:41 am
2 people liked
gb160
(@gb160)
Estimable Member
RE: VFA Artifacts on X+Y Straight Edges

Well the new belt tuner doesn't even work on my iPhone X. Great Job Prusa 😂

It's incredibly dumb that if you use the web app it's telling you should be tuning to a certain frequency, if you use the Prusa App it's suggesting a different frequency. Surely it would make sense for these 2 methods of tuning to go live at the same time to avoid confusion ?

Posted : 18/07/2025 7:29 am
1 people liked
gb160
(@gb160)
Estimable Member
RE:

Well the updated tuning web app doesn't work on my iPhone X or my iPad mini 5. The only device I can get it even registering audio on is my MacBook Pro, and it's now somehow worse than it was previously, even with the waterfall plot. 
A tiny adjustment (about 1/16 of a turn) is the difference between reading 80 Hz (far too low)  , and 120 Hz (far too high).
I have almost zero background noise.

A complete horror show of an update IMO.

Posted : 18/07/2025 7:43 am
Page
 Page
(@page)
Active Member
RE: VFA Artifacts on X+Y Straight Edges

 

Posted by: @gb160

Anyone tried the updated  belt tuning guide ? The web app now has the waterfall plot which will hopefully make tuning it easier, and the tuning instructions have now completely changed, target frequencies are higher, although that might be related to the new position of the extruder when tuning.

Any effect on VFAs?

 

https://belt.connect.prusa3d.com/

I tried it now. But this settings completely skewed my gantry. It is not rectangular and I have about 4mm gap on the left front corner...

Posted : 18/07/2025 7:55 am
gb160
(@gb160)
Estimable Member
RE: VFA Artifacts on X+Y Straight Edges

 

Posted by: @page

 

Posted by: @gb160

Anyone tried the updated  belt tuning guide ? The web app now has the waterfall plot which will hopefully make tuning it easier, and the tuning instructions have now completely changed, target frequencies are higher, although that might be related to the new position of the extruder when tuning.

Any effect on VFAs?

 

https://belt.connect.prusa3d.com/

I tried it now. But this settings completely skewed my gantry. It is not rectangular and I have about 4mm gap on the left front corner...

I couldn't even get as far as completely skewing my gantry 😂

All jokes aside, my patience is wearing incredibly thin now. It's absolute amateur hour.

Posted : 18/07/2025 8:04 am
Page
 Page
(@page)
Active Member
RE: VFA Artifacts on X+Y Straight Edges

I don't understand that either. I'm going to support what they meant by that 😀

Posted : 18/07/2025 8:07 am
SgtCaffran
(@sgtcaffran)
Estimable Member
RE: VFA Artifacts on X+Y Straight Edges

 

Posted by: @page

 

Posted by: @gb160

Anyone tried the updated  belt tuning guide ? The web app now has the waterfall plot which will hopefully make tuning it easier, and the tuning instructions have now completely changed, target frequencies are higher, although that might be related to the new position of the extruder when tuning.

Any effect on VFAs?

 

https://belt.connect.prusa3d.com/

I tried it now. But this settings completely skewed my gantry. It is not rectangular and I have about 4mm gap on the left front corner...

Did you square your gantry with the belts completely loose? So with the tensioners removed? If not, I suggest you do that first and only then run the belt tuning.

Posted : 18/07/2025 8:09 am
1 people liked
Chris Hill
(@chris-hill)
Honorable Member
RE:

I just tried the new web version.  My belts were previously set by the old method, but I had slightly higher tension than the old 85Hz recommendation because it seemed to improve VFAs with my GT1.5 belts.

When I checked just now, using the old method, the left belt measured 94Hz and the right 93Hz.  Without any adjustment, measuring at the new locations I got 90Hz for the upper and 84Hz for the lower.

So then I adjusted the upper to 98Hz and the lower to 92Hz, as per the new instructions.  I then remeasured at the old positions and got 103Hz for both sides.  Gantry still square.

This is on an iPhone 13 Pro, and the results were quick and easy - the waterfall plot is a nice extra, but I didn't need it for the measurements.

My take-away from this - Prusa seem to be aiming for a somewhat higher tension than before - 103Hz in my case, versus the old recommendation of 85Hz - and they've moved the measurement point probably just to make it easier to access and easier to guarantee a repeatable gantry position, but the result, when both belts have the same tension, is slightly different readings (upper versus lower) due to the asymmetric position of the print head.

 

Posted : 18/07/2025 8:12 am
1 people liked
Page
 Page
(@page)
Active Member
RE: VFA Artifacts on X+Y Straight Edges

Yep at the very beginning. I also aligned the gantry according to the video from Prusa. The gantry is with loosen belts with zero gap in the front.

Posted : 18/07/2025 8:14 am
Chris Hill
(@chris-hill)
Honorable Member
RE: VFA Artifacts on X+Y Straight Edges

My TPU tension idlers don't seem to have changed anything with respect to the frequency-dependence of the belt ripple on my GT1.5 setup.  I tried two different versions - one solid TPU (quite a hard TPU I think - there's no rating on the box), and one made deliberately more compliant by hollowing out the centre section (see photo), but the VFA test print looked the same in each case, so I'll be swapping back to the original idlers and patiently waiting for @malpan to start selling his compliant pulley's in his web shop 🤣 .

Posted : 18/07/2025 8:21 am
2 people liked
SgtCaffran
(@sgtcaffran)
Estimable Member
RE: VFA Artifacts on X+Y Straight Edges

Can you try the silicone mod with a small piece of silicone underneath the bolt that sits in the printer tensioners?

Posted : 18/07/2025 8:25 am
SgtCaffran
(@sgtcaffran)
Estimable Member
RE: VFA Artifacts on X+Y Straight Edges

 

Posted by: @page

Yep at the very beginning. I also aligned the gantry according to the video from Prusa. The gantry is with loosen belts with zero gap in the front.

Do you have the exact same number of teeth pulled through the Nextruder carriage for both belts and both sides?

Maybe try again. I have already seen examples where both the squareness of the gantry and the belt tension is equal with the new tuning method. Might be some user error somewhere.

Posted : 18/07/2025 8:27 am
Chris Hill
(@chris-hill)
Honorable Member
RE: VFA Artifacts on X+Y Straight Edges

 

Posted by: @sgtcaffran

Can you try the silicone mod with a small piece of silicone underneath the bolt that sits in the printer tensioners?

I was thinking maybe of the silicone tube around the pulley spindle (bolt) that was suggested earlier.  I think I may have some silicone vacuum tube (intended for a carburettor), which hopefully has a 3mm centre bore - then I'd just need some slightly different bearings, and probably a printed pulley in something rigid - maybe ABS - to accommodate the bigger bearings.  Not likely to get to this for a while though.

Posted : 18/07/2025 8:35 am
Page 51 / 62
Share: