VC4 500 - Looks all over the place
I simply cant make sense of it
54 Replies
@chicken bump :)
Still at the commisioning stage, without Y belts
so yah you have something going on 🙂
hows the belt tension graph look first of all?
your amplitude for this looks really low
Also pretty bad tbh, will send them
first one
second
also are you using the toolboard or beacon to do resonance testing?
I guess the toolboard? I just pressed "Generate shaper graphs" in RatOS
go into configurator tab and select setup wizard from the left toolboard, then click hardware selection on the right side and then scroll down
Yes, they are set to Integrated On Toolboard, both
yah the belt graphs are not good, there should be two spikes, the first spike is the y axis and the second is the x axis. Whats the difference between your two graphs? Just two different runs?
Yeah basically. I mean there's a 4 hour difference. But the only real thing I did in that time was connecting the orbiter filament sensor, and tightening everything down on the toolhead with tie-wraps
the tightening of everything down with tie-straps explains why the 2nd one is cleaner in the 80hz+ range
whats strange is why the lower belt did not spike
I do have this one problem where it seems like my belts are rubbing, and Im not sure why. I tried to precisely position them in the center of the bearing/pully, but when I move in one direction the belt creeps up, and the other direction it creeps down
something is really binding or dampending things
Maybe there is too much tension on the belts?
the belts are spiral cut off a much bigger closed belt so they are going to wonder up and down. Very normal. You just dont want them to stay stuck up against the side
Because I did have to tighten down the left belt quite a bit to get my gantry straight after installing the belt
The timing on creating this thread is not impeccable btw, I don't have too much time. But at the moment I'm kinda at a loss. The machine seems to work decently, yet my graphs are all over the place
its all good. was just trying to find a link. tg73 has a good starting point for belt tension https://discord.com/channels/582187371529764864/1223286652949106748/1272625387871928494
home the printer
then go into real time analysis and then pluck the belts on the left and right of the toolhead
https://discord.com/channels/582187371529764864/1287985300471025709/1287985300471025709 is a thread I helped someone on with a similar belt tension graph. I would worry about getting that at least somewhat clean before you worry about shaper graphs
for the 500mm machine I would tune to 85hz. Look in that other thread and I posted a video in the middle of it on me plucking the belts and how to read them
also if things are not aligned we can loosen either the jointer plate bolts to the y carriages or the jointer plate bolts to the x gantry and get things striaghtened up. I suspect its one of those two is off and causing some binding. Let me know when you have some time to do some testing
Thanks so much for the information/sources! I will look into it tomorrow, gonna grab a few drinks ;)
party on!
Okay that real-time analysis tool is actually so sick
Currently tuning to 85.4Hz
yeah I also was kinda afraid that could be the problem, don't know how much effort that will be. Running a belt tension graph now
Seems better than the previous one, I guess?
Gonna try a shaper graph just to see if there's any difference
Damn that improved a lot
Tho one of the blue peaks is missing here?
Had the same problem as you with only one peak. I then added one more tooth per side and then I had 2 peaks. It also straightened the axle for me. Before that it had a gap of 2mm on the left side when it was right at the front. I loosened the clamp at the front of the print head and moved it one tooth further. Apparently the belts were not the same length. If they are set too tight, I always have the problem that a spike disappears, see my documentation here: https://discord.com/channels/582187371529764864/1292213095757774879
whoops I didnt realized it created two graphs :facepalm:
thanks for the info
Now that I've tuned my belts, I got my 2.09mm gap back
It's not straight indeed
There is a gap on my left side
Hmmm, this cant be good either
Welp, time to loosen the belts I guess.
This is with both tensioners at the same distance. There is way more tension on the bottom belt
I must have opened and readjusted the straps on the back 5 times until I had it reasonably straight. I also opened the screws that clamp the X a few times until everything finally fitted. I then took out the last mm through the tooth at the front of the head until everything was perfectly aligned. I feel more like a beta tester than if I had bought a finished product. 😂
Hmm, my gantry indeed is not aligned well. Maybe it's as easy as losening the bolts on the X/Y joiner and straightening it out?
I'm not an expert on the subject, I can only tell you what I did. There are 3 screws per side. One at the top, 2 at the bottom. Then move the gantry back and forth several times. Then test the stop at the front and rear. It is best to remove the Y end stop for this, it is only one screw, otherwise it will increase the distance at the front left.
lmao I just realized I could have indeed just undone the bottom and top 2
I literally loosened all of it
The gap just doesnt want to go away
I think I got it, I also loosened the ones on the carriage, seemed to help
:)
bom
I have not seen a graph yet that has a bigger peak on the lower frequencies, is this an issue @chicken ?
Some people have it that way. Shaper results are what matter and your Y numbers are great
X looks a little off on the shaper graph but klipper can only handle max acceleration settings for the entire printer so you go with your lowest which is always the Y axis on a coreXY as it weighs a lot more.
I would call this a win and move to hybrid
You still have the gap? Sorry just getting caught up on reading. If you want to try and fix that you can loosen the 4 screws on the y jointer plates that attach to the carriages and move the gantry back and forth 8-10 times and see if it straightens out. Be warned though this could set you back in your belts to square one.
No problem, I'm already grateful someone's helping me 😂. But yeah, the gap is completely gone now.
Yeah I had to redo my belts
But at least I knew what I was supposed to do now, so I did it correctly
Party on then. Either take those numbers and plug them into your printer cfg and slicer or get hybrid going
Im gonna try using these values first, see if I can get it to work properly, and then do hybrid I think.
Thanks for the help btw
You are welcome. Just make sure to use mzv numbers even if zv is recommended. Get better results and then plug the y mzv number as your external parameters acceleration in the slicer
uuuh, isn't the axis noise supposed to be under 100 on all?
are you using the toolhead for resonance?
I would assume so
Or is it not related to the accelerometer settings in the configuration wizard?
It is the ones set in the config wizard. I don’t know why you would have noise like that on a built in adxl on the ebb42. Might want to ask over in the electronics channel and see if anyone has any ideas.
For some reason it's good now. I really don't know what changed.
strange. glad its working
Hey @chicken , aftere adding the hybrid belts and tuning those to 95.5 Hz, my other belts are off.
The top belt now resonates at 90Hz and the bottom at 78 or so
Should I keep it that way or adjust the tension?