Verify Belt Tensions...

[LostFool]

Voron 2.4 r1 350mm z belts = LL-2GT RF

Literally not possible to get them to the recommended ~7.05mm deflection. Stuck at ~5.8

How can we determine these numbers to create our own belt charts?

[SamppaD78]

I have exactly the same issue. Voron 2.4R2 300 build,correct belt length,using belt tension tool BTT belter and yes cant tightened Z belts to correct value that is stated in BTT chart.For Z stated deflection value -7.2 (21N??) and for AB belts -5.5 (8,5N) I'm stuck at 5.8 with Z belts, same as you because there is no more adjustment on my tensioners. I'm using gates belts with chaotic lab CNC tensioners. BTT customer support stated that when value is lower then belt tension is higher?? So what to do with this issue?

[SamppaD78]

I have contacted Biqu support,lets hope they can help with this issue . 21N for a Z belt tension cant be correct for Voron 2.4

[LostFool]

Awesome, appreciate the effort. I have so little time in my day

On Wed, Sep 11, 2024, 9:11 AM SamppaD78 @.***> wrote:

I have contacted Biqu support,lets hope they can help with this issue . 21N for a Z belt tension cant be correct for Voron 2.4

— Reply to this email directly, view it on GitHub https://github.com/bigtreetech/Belter-belt-tension-Tool/issues/2#issuecomment-2343789230, or unsubscribe https://github.com/notifications/unsubscribe-auth/AIIPGWM3OFE3VYYTRZCJNDDZWBFPZAVCNFSM6AAAAABNHLC4QCVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDGNBTG44DSMRTGA . You are receiving this because you authored the thread.Message ID: @.***>

[SamppaD78]

No problem. Lets wait and see what support has to say.

[V8coyote43v3r]

Update the Belt Tension GT2 RF (N) values in colum b with actual tension, everything else will change automatically.

[BTTJUSTIN]

Please print and install ProbeTip.step to ensure accurate reading https://github.com/bigtreetech/Belter-belt-tension-Tool/tree/master/PrintParts

[SamppaD78]

Hi. Installed the printed part and still max deflection of the belts is at -7.02 thats about 19.98N. Spec value is 20.04-25.8 I tried the B colum update values but nothing changes for me,only when values are updated on the belter displayed values chart is that i get the reading for tension.

[rongith]

I have completely different values for a corresponding table mm / N.

I attached spools of filament of different weight to a suspended 9mm belt. Here my results:	Spool weight (kg)	Spool weight (N)	My deflection (mm)	Biqu deflection (mm)
0.325	3.19	3	4.8
0.565	5.54	4.4	5.1
0.861	8.45	5.2	5.5
1.130	11.1	5.7	5.8
1.580	15.5	6.1	6.4
1.935	18.9	6.3	6.9
2.305	22.6	6.4	7.3
3.205	31.4	6.7	8.5
4.255	41.7	6.9	9.8
infinity	infinity	7.6	infinity

How can the tension be proportional to the deflection according to your calculation sheet (you found a linear regression)? How can you reach 12mm deflection (under 58N tension) as with a straight belt (1.5mm thickness), the deflection would be 7.6mm, the maximum value?

According to your linear regression, 1000N would be 135mm of deflection.

Something is very wrong here or I didn't understand at all how your equipment run.

[SamppaD78]

Hi. I'm not a expert on belt tension. This info is what tool and calculator is providing . I purchased this belt tool to use it with tensioning Voron 2.4R2 belts. Now there is definitely a issue, is it a user ,tool,or calculator provided related I don't know,but we are here to find out. How I use this tool, zero out the tool,attach the tool to the belt and get the reading from the tool. Tool display -7,01 with plunger attached to the tools shaft. I open the belt tension calculator,under printer type and model column select Voron Z belts,under Belter displayed value mm column I added tool displayed value -7.01 and press enter. Calculator Belt tension column display value of 20,075. Recommended tension column is showing recommended tension value of min 20.4 and max value of 25.8 and last column is reporting that belt tension is out of range.

I would like to find reason for this issue,so help is appreciated.

[SamppaD78]

I got email reply from BTT tech support on this issue

[support01@bigtree-tech.com,]

Hello sir, I asked about this kind of situation. Because the printout is installed or the printout itself or even the probe itself has differences, the actual measurement value will be inaccurate. We will set a standard in the future. Please wait patiently.

Looking forward to your reply.

Best Regards

Biqu

[rongith]

I would like to find reason for this issue,so help is appreciated.

Yes for me there is something wrong in the Biqu methodology. I made myself some measure to ensure I have some reliable results.

And how would you know the probe "needle" go as far as intended in the probe tip? You may have an offset.

I designed the joined part as a reference to check I got every time 7.6mm (in my case) before measuring the belt. That way and because I done my own reference measurement, I'm quite independent of the probe tip print. It is like to have a straight belt 1.5mm thick. Plat-r00b - Defaut.zip.

I don't understand how Biqu can have 9.22mm like in the manual. I got 7.6mm maximum.

[SamppaD78]

Hi. You are right,I cant understand the way Biqu is thinking about this design,tool and way it should work. Thanks for providing zip file. I will print it and test when i get the time. Its a bysy time at work with long shifts ..

[noonien]

I'm having the same issue, after calibrating to a 110Hz tune on the A/B belts, this tool reads a value of 5.5 - 5.6. The calculator is useless, therefore the tool is useless for measuring absolute tension.

It can, however, be used to measure relative tension, to ensure belts have the same tension, however, I've achieved basically the same thing using this simple print.

Don't waste your money and time with this "tool".

[SamppaD78]

You are right. Tool is worthless if you cant trust the calculator or the tool displayed values..waste of money and time . I was using this and it was working well for me. https://github.com/Diyshift/3D-Printer/tree/main/GT2%20Belt%20Tension%20Meter

[BTTJUSTIN]

Hello，this is Justin from BTT, We have realized that there are errors in the calculation tool, Our engineers are hard at work trying to develope a new calculation tool to enable more accurate tension results, Please give us some time to remedy this issue, Thanks you for your patience.

[LostFool]

Hello，this is Justin from BTT, We have realized that there are errors in the calculation tool, Our engineers are hard at work trying to develope a new calculation tool to enable more accurate tension results, Please give us some time to remedy this issue, Thanks you for your patience.

Thank you for looking into the issue. I will eagerly awate the update. I know it's hard with so many variables

[SamppaD78]

Hi. Nice to see that someone is taking this issue seriously , and is making effort to solve this issue. Thanks BTJustin,we will wait for a solution.

[reneleban]

Hello, the biggest problem seems to be the printed part, and how deep to insert the pin. If you push all the way to the bottom, I'm at 7.84. With the printed part from rongith, if I just insert it until the resistance of the printed part rises, I have a value of 9.38.

Maybe a printed part like that and a “reference value” to convert the effective measurement in Excel could be the solution.

btt could print the part, measure the reference value for the given values in the table, we print the part and could insert the measured value in a specific field, and the “belt display value” for the calculation of the “belt tension” field could be converted in the calculations.

[rongith]

It is not only the initial offset that is an issue, it is also the relation model between the displayed value and the tension in the spreadsheet. BTT propose Belt tension (N) = 7.673640167*ABS(Belter Display Value(mm))-33.7167364. But the relation model can't be linear. When the tension is infinite (straight belt), the display value should be less than 8mm (about 7.6 in my case). With the BTT model when the tension in infinite (straight belt), the display value should be infinite too. :-o

[SamppaD78]

You are right. Offset and displayed values in the spreadsheet are the issue. At this point the best that this tension meter is able to do is to confirm that all belts are at the same tension and that all. Biqu support is handling this issue so lets hope they fix the calculator and printed part.

[reneleban]

well, you could maybe think the different way measuring the tension. Actually there are negative values because zero is the loosest tension (we maybe never will get there). But if we take a printed part, zero it out at the measured position with the printed part, and then measure the tension, we would only get the positive distance. I did not try this, but maybe the measured distance is to low.

Will try it later if someone is interested. Maybe its only brainfuck.

[zlatkomos]

Is there any news about solving this problem?

[BTTJUSTIN]

Our engineers are still hard at work developing a more accuracy conversion calibration tool, Please give us some more time to perfect it. Thanks for your understanding.

[SamppaD78]

Also waiting for this issue to be resolved. At the moment calibration tool is collecting dust at my workbench as at this point of time its only good to confirm that multiple belts are at the same value but that value is not calibrated correctly due to calibration software issue. Lets hope that BTT engineers find a solution to solve this issue.

[zlatkomos]

Our engineers are still hard at work developing a more accuracy conversion calibration tool, Please give us some more time to perfect it. Thanks for your understanding.

please let us know here when the solution is ready. thanks!

[auggie246]

Our engineers are still hard at work developing a more accuracy conversion calibration tool, Please give us some more time to perfect it. Thanks for your understanding.

It's too late and unacceptable. How can the excel sheet be right when the maximum possible deflection from a totally flat belt is only around 7mm and the excel sheet shows to get 20+N requires 7+mm deflection.

PLEASE hurry, at this point, I would rather make the 3d printer version with a proper calibration method

[checkitog]

I just received the tool but the calculator is useless for a Voron 2.4, when will this update be available?

[SamppaD78]

I just received the tool but the calculator is useless for a Voron 2.4, when will this update be available?

I don't know,I have the same issue and I know that BTT support is urging the solution. I have been waiting for some time now. At the moment tool is collecting dust at my workbench . Thinking that printing a 3d version would be easy and just adjust belts based on that printed tool.

[auggie246]

I just received the tool but the calculator is useless for a Voron 2.4, when will this update be available?

I don't know,I have the same issue and I know that BTT support is urging the solution. I have been waiting for some time now. At the moment tool is collecting dust at my workbench . Thinking that printing a 3d version would be easy and just adjust belts based on that printed tool.

Same sentiment, essentially a waste of money at this point. Have already printed the parts and waiting for my piano wire for calibration

[zlatkomos]

I would ask the guy from BTT to convey this to his superiors. that means you produced something that doesn't work and thereby misled your customers, so it's a fraud and the price is not important that's why I invite everyone who bought this device to organize together to get our money back, and I won't even talk about the reputation of BTT, producing something that doesn't work is not right

if I don't get an answer in the next 3 days I will spread all this on all social networks that it is a pure scam

BTT should be ashamed.

[SamppaD78]

Well,its a problem that needs solution. Selling products that are not as advertised, is bad for BTT reputation. After all 3d community is purchasing BTT products on a big scale,most of the times there is no issues but no one is perfect. Sometime there will be issues with product hardware or software and giving a feedback should lead to solution . I had some issues with my SKR board that failed on a firmware update due to power lose at home braking bootloader,contacted BTT for help and they contacted me back providing all the files and how to guide to fix it myself.It took like a week for them to contact me. So I do think that people are doing they best to help community and solve this problem,just give them some time.We can print 3d tool to adjust belts in meantime.

[zlatkomos]

.... if I wanted to make a tool, I wouldn't bought it from BTT.

I am saying here that the product was made - released for sale without being tested!!!! that's the problem

if they had tested it they would have seen for themselves that they had that problem and would have fixed it before going on sale. that's what I'm talking about.

this is not some quantum physics with a million variables that cannot be tested, especially since the device is intended for the majority of the Voron community

[checkitog]

Well, let's have faith in BTT, I have many of their products and they all work very well, it is true that the tool itself is not very useful, but let's hope that they will solve it, money is not a problem, what we all want is a easy and accurate way to measure our straps, let's wait a while to see if it is solved

[auggie246]

.... if I wanted to make a tool, I wouldn't bought it from BTT.

I am saying here that the product was made - released for sale without being tested!!!! that's the problem

if they had tested it they would have seen for themselves that they had that problem and would have fixed it before going on sale. that's what I'm talking about.

this is not some quantum physics with a million variables that cannot be tested, especially since the device is intended for the majority of the Voron community

.... if I wanted to make a tool, I wouldn't bought it from BTT.

I am saying here that the product was made - released for sale without being tested!!!! that's the problem

if they had tested it they would have seen for themselves that they had that problem and would have fixed it before going on sale. that's what I'm talking about.

this is not some quantum physics with a million variables that cannot be tested, especially since the device is intended for the majority of the Voron community

this is so right. I don't understand how the engineers can be hard at work at something that is technically not difficult. in fact if I follow the calibration method shown here, I would have it done within a day @BTTJUSTIN

[auggie246]

Still no resolution from BTT... 3 months after this issue has been created

[zlatkomos]

.... and BTT still sells that product even though they know it's useless!!!!!!

shame on BTT and your "engineers"!!!!!!!!!