Belt Tension Adjustment  

RE:

There used to be a video on the instructions page, but it seems to be gone.  I wonder if they accidentally removed it. 

In summary move the gantry in line with the z lead screws.  Then move the print head all the way to the left.  Using the belt tuner strum the belt on the right side between the 6th and 7th hole on the linear rails. 

After adjusting to within limits move the print head all the way to the right and repeat the same process on the other side 

Then follow the rest of the instructions on the instructions page.  Hopefully the video will return.

RE: Belt Tension Adjustment

Thank you, I didn’t understand the subtlety of moving left to right between the two measurements. I’ll test it tonight because I think my tension is not good at all at the moment—too tight on one side.

RE: Belt Tension Adjustment

The video is up again when I checked yesterday.

However ... after using that last year several times successfully (well - it worked soso lala, not great, but somewhat). Now it seems to be broken and I tried on different cell phones (Samsung Galaxy 25S Ultra, iPhone 12, ..) for hours. I guess that new versions of power management / browser / .. seem to make this tool unusable for me.

I recall that there were some belt tension tunres for the MK3/4 which you can print yourself.

Question: Does anyone know if / how those could be used on an XL? (The Phone does not work for me anymore...)

Many thanks in advance for any insights!

RE: Belt Tension Adjustment

As a follwo up - I was doing the belt tension adjustment with a 14" notebook which fits into the alotted space. That works ... soso lala. The values jumped between 60, 80, 100, 120 - or similarly up and down. I think that I got it in the end, but it is more a feeling than certainty. 

Any other, more direct, method would be highly appreciated! 

Would this work: https://www.printables.com/model/1166964-prusa-mkxlminicore-6mm-belt-tensioner-6mm-merka-re ?

RE: Belt Tension Adjustment

To follow up on this topic, I finally managed to properly tighten the belts. The key is to move the carriage to the center at the level of the Z-axis screws, then move the carriage to the left to adjust the right-side tension, and to the right to adjust the left-side tension.

RE: Belt Tension Adjustment

Many thanks!

I also did do some follow up research and here are my results:

0. Using Audio it is important to be in a silent room without fans and other noises as that had already an impact for me.

1. Phones: I used them in the past and they worked, then the Android phone stopped working (due to power management I assume [... can explain]) and then I have seen the same on an iPhone. It appears that they do not really get "real time" processing and instead get once in a while some CPU to do their thing - but that isn't enough and leads to unpredictable results.

2. Using a small PC/Mac: Works (soso lala). However - there is always a divergence through harmonics which makes the exact read out .. tricky and finnicky..

3. I then printed this tension meter and used it - and it was showing me that my audio measurements were in range. The left side was dead on, the right side was close to the borderline. After correcting (much smoother) it seems to work as expected. The important thing: You still need to move the carriage to the same locations to do these measurements, but then it works much faster, predictable and reproducible. ==> I will use this going forwards until there is a real app (not web app) which works properly.

I hope this helps!