Idex400 - Offset issues X Axis
Dear all .... I still got an x axis offset of about 0.4 - 0.5mm in x axis direction regardless what I'm trying 🙁 First things first - I triple checked ALL belt length - both heads, both hybrid .... they are exactly same in lenght - also in the clips - same amount of teeth.
Tensioning is done with GATS at 28NM ... erverything is perfect aligned .... even without skew compensation the printer is in a very good shape.
I'm really frustrated meanwhile .... I did the whole setup process a couple of times .... all the results are "very good" but it always ends up in a x-axis offset 🙁
Any Idea what I'm doing wrong? please let me know if I've overseen something.
Thank you sou much and BR,
Volker
Current Printer Skew:
XY Skew: 0.000567 radians, 0.03 degrees
XZ Skew: 0.000000 radians, 0.00 degrees
YZ Skew: 0.000000 radians, 0.00 degrees
VARIABLES:
[Variables]
idex_applied_offset = 1
idex_xcontrolpoint = 161.42136241545052
idex_xoffset = -0.029013430044699362
idex_ycontrolpoint = 431.5710000000001
idex_yoffset = -0.07912753648571424
idex_zcontrolpoint = -0.5
idex_zoffset = 0.0075000000021767654
idex_zoffsetcontrolpoint = -3.6765624999771735
nozzle_expansion_applied_offset = 0
nozzle_expansion_coefficient_multiplier = 1.0
nozzle_expansion_coefficient_t0 = 0.06
nozzle_expansion_coefficient_t1 = 0.06
t0_filament = ('', '', 0)
t1_filament = ('', '', 0)
13 Replies
here you can see the gap .... before starting the print I do of course VAOC calibration! Nozzles are perfectly aligned , but still this offset while printing 🙁 Is it possible, that my endstop switches do have an issue?
You ran these steps in the commission guide?
12. Run the following command:
_VAOC_RESET
13. Make a new VAOC nozzle alignment procedure by repeting steps 5, 6, 7 and 8.
Validate the calibration:
Open the ratos-variables.cfg file inside the machine tab and check the idex_xoffset value, if the value is higher than 1.0mm or lower than -1.0mm then the printer suffers from mechanical issues like a skewed gantry and/or uneven belt tensioning or belt length
Sure, more than once 😔
Offset value extreme low -0.029
Many of us have this issue. It is an unknown error being introduced into the VAOC. There are several theories where this error comes from. It is not in the VAOC calculation, it is being introduced somewhere else. It is not a frame, belt or skew issue as the error is almost always around -0.5mm and it is always the x axis. I manually alter whatever the VAOC calculates for Xoffset in the ratos-variable.cfg by subtracting 0.5mm from the xoffset result. Since I only need to do the VAOC once every month or so, it's not too big of a deal.
@billyd Hmmm, interesting. Yes it is about 0.5mm - always to the same side. Yesterday I tensioned all the belts once again with my GATS to 40Nm ... a bit more than I usual do, doing all the calib once agian .... same result with more tension ... about 0.5mm off 🙁 So I started to try different ideas. Right now I do have some "OK" results when I "calibrate" the T1 nozzle an "diameter" to the right side in VAOC .... means I calibrate the Offset optical not by adding 0.5mm to the variables. It's better yes ... at least it is now possible the print support material 🙁 It is extremely frustrating 🙁 Billyd ... thank you so much for sharing your experience!
... but the means .... it a waste of time if I setup the whole RatOS from scratch .....
It is probably more accurate to do the VAOC per the instructions and manually alter the ratos-variables.cfg file since trying to compensate by eye on camera is likely inaccurate. I did request in the ratos-development section that mikl add a user variable that automatically adjusts xoffset by a user supplied amount since this problem is pretty common. But mikl is very busy and there haven't been any updates for quite awhile.
@billyd yes you are right ... tried a lot the last days, but best results, as you told me, when I manually Edition and add .5mm to the calibrated offset 👍
... but tbh, I'm really disappointed about VC4s quality and also support😖 This is really not the cheapest printer and after my perfect working VC3.1 this is a huge step back ... at least the Idex Feature.
3 weeks ago I bought a H2S cause I need a reliable printer ... dont get me wrong, I'm a RatRig fanboy and was soooo happy when my VC4 arrived😎
@billyd once again ... thank you so much for helping me😊 💪
Yes it is quite difficult to get the IDEX working on the vc3.1 level. But it can be done with hardware upgrades and careful building and tensioning. Mine is excellent but it took me about 4 months to do it.
Yes frame is also perfect aligned on my one, nearly no skew and Tenesioning with GATS, erverything is runni g very smooth. TI upgrade against "heatsoaking troubles" so yeah - as long as I'm just using one head it a good working printer😉
@billyd One last question .... which tension do you use for your belts? Right now I'm running 40N ... but seems a bit too much, since my pulleys start doing strange noises ... but Gates statet 6lbs/span which means if I use the GATS on the front with 2 spans, I should go for 12lbs which is about 55N?
If you have a high pressure linear rail on the X axis and machined Y belt bodies you can tension to 55N without issue. However with the stock linear rail on X I wouldn't go that high you could damage the toolhead carriages. And on Y if you are using the printed y belt bodies they will shear at high belt loads on the hybrid belts.
That's way too high. You want it just tight enough to not skip.
@TheTik okay ... thanks ... I'll go back to 25-30N .. good to know 🙂