VC4 300 Enclosed - Belt tension gantry alignment
I'm trying to do the belt turning but having some issues, hope someone can give some pointers.
When I try to align the two peaks the gantry goes out of alignment.
Is it because the upper belt is longer then the lower belt?
![No description](https://cdn.answeroverflow.com/1265337628656402432/belt-tension-resonances-2024-07-23-165657.png)
15 Replies
Yes your lower belt is tighter since it’s the higher frequency, 80hz vs ~73hz. If you want to get them to match you need to get the belts exactly the same down to the tooth. The measurement is belt clamp to belt clamp. You could have 20 teeth more hanging out of one of the belts and that would not directly show on the graph. It could add some more noise but the peaks are belt clamp to belt clamp. Make sure you do not cut your belts to short. I have a have 15mm+ of extra belt hanging out of the back clamps
Thanks man. Will try to see if I'm able to fix it or if not then I just buy some new belts 🙂
Do you not have any extra belt hanging out of the back clamp?
Nope i already did the cut before doing the tuning 😦
I left about 6-8 teeth extra once I was sure the belts were exactly the same length.
![No description](https://cdn.answeroverflow.com/1265410268238839809/image0.jpg)
Yep i only have like 1-2 teeth...
https://discord.com/channels/582187371529764864/1246891806520639552/1257830057951498250 use something like that to measure the belts the same
Do you have enough to loosen the front blocks to get enough to tighten the upper belt and leave the lower one alone?
But i was able push the top belt to be tighter by pushing it from the other side by using pliers
You want both belts to use every tooth in the front blocks
The belt was first placed on the front block and then routed to the back
Will do a new tension test tomorrow and see if it a little better, but thanks anyway 🙂
@chicken So I keep coming up with this graph, would you say that's fine or should I keep trying to fiddle with it? 🤔
![No description](https://cdn.answeroverflow.com/1265611495048478791/belt-tension-resonances-2024-07-24-110540.png)
Worry more about the frequency matching than the amplitude. Your upper belt is not as tight as the lower belt since it’s 3-4hz lower. You might want to try slightly, i am talking like 1/32 to 1/16 a turn tighter on the upper belt and see if you can get the hz of that 2nd spike to line up better. Otherwise I suspect it’s perfectly fine to run with. What does a shaper graph look like?
@chicken ok so far I've checked the belt length is the same by taking them off, holding them side by side and by pulling them tight, then but them back on checking they are not binding, and are using all the teeth both on the front and the back. I've got them on the same frequency and the shaper looks fine the me by my knowledge. The gantry is not hitting the front on both sides at the same time, but the beacon gantry twist reports the following:
Gantry twist relative to the center
Very low gantry twist: 18.700545μm.
No beacon scan compensation needed.
![No description](https://cdn.answeroverflow.com/1266371956840599603/belt-tension-resonances-2024-07-26-123055.png)
![No description](https://cdn.answeroverflow.com/1266371957272870932/resonances_y_2024-07-26-123916.png)
![No description](https://cdn.answeroverflow.com/1266371957666873454/resonances_x_2024-07-26-123906.png)
Update for anyone else: after a lot of tweaking I've got it to around this with out hybrid, and I'm content now. So for anyone else make sure belt's are same length and take it slow and take lots of measures with the belt tension. 🙂
![No description](https://cdn.answeroverflow.com/1267824484682039440/belt-tension-resonances-2024-07-30-124234.png)
![No description](https://cdn.answeroverflow.com/1267824485155868757/resonances_y_2024-07-30-125312.png)
And after hybrid mount:
![No description](https://cdn.answeroverflow.com/1267824600625053788/belt-tension-resonances-2024-07-30-132517.png)
![No description](https://cdn.answeroverflow.com/1267824600943689859/resonances_y_2024-07-30-133021.png)