VOAC calculating offset wrong by the same amount every time
Just like the title says, my X offset between T0 and T1 is always wrong by 0.9mm in X (Y is perfect). Any idea on what would cause this? My frame square and both toolheads print really well. Skew calibration prints close to perfectly for each.
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Best guess is that your pxprmm setting is off.
I fixed it temporarily by altering the idex_xoffset in the ratos-variable.cfg.
How does the VOAC calculate offset? I am guessing it is using the x endstops? Problem with that is there a ton of tolerances involved that can build up in the wrong way.
by checking how many px's you dragged the image to align T1 relative to T0.
It's not using the x endstops.
Those are only used for homing
Ah pixels/mm. But I am lining up the the nozzle diameter really closely. Hard to believe I am almost 1mm out. I do the calibration until it repeats perfectly. I do notice that sometimes when I drag the nozzle in the image, it doesn't move completely in terms of the amount I move it. It does at first but repeated moves without changing from t0 to t1 or vice versa result in ever smaller movements relative to how much I drag it. Almost like there's a buildup of error, perhaps in the software?
from what I've noticed in the past is that it works better if you do only one move per toolhead at a time. doesn't matter if it's not perfectly aligned after one move, just switch, do one move, switch back and continue like that - get's me aligned in 2-3 moves typically
Yes I started doing that as well. I just find it interesting that the software is doing that. It seems like a bug. But maybe not, you can fill a lot of libraries with stuff I don't know lol At any rate maybe it's related to my issue.
Almost like there's a buildup of error, perhaps in the software?No that's because your pxprmm is wrong. Make sure you've set the correct nozzle size in the configurator, you might be trying to match an improperly sized circle because you haven't told it what nozzle you're using. The inner ring is the important one the outer ring can be set via the diameter input in the settings dialog
Yes I have this exactly matching. It has to be something else.
How far off would I have to be to be creating a 0.9mm difference?
Can you show me a screenshot of the nozzle matching the crosshair with the settings panel open?
Depends on how much adjustment you need, and how many times you drag it because it doesn't move to the spot you dragged it to (because the pxprmm calibration is wrong)
If the nozzle doesn't end up at the crosshair, your pxprmm calibration is wrong.
Each time you drag the image, you add error.
Will do in a couple hours I am printing something until about 630 pm est
The last pic is an IDEX calibration I just printed. If you're not familiar with this model, it demonstrates physically where the two idex toolhead are in relation to each other with T0 as the reference (orange) and T1 as the measured offset (yellow). The first tick closest to x or y is the zero mark where the offset would be perfect. In my case, the Y axis is pretty much dead on. On the x axis you count in .1mm increments from left to right (starting at zero) until a yellow tick lines up with an orange one. In this case it's about -0.7mm to -0.8mm out and this after the ratos offset is applied, in my case -0.14565 for a total of what it should be is -0.84565 to -0.94565 or about -0.9mm
Double checked configurator I have it set for a .4mm nozzle which I am using on both toolheads.
What is the offset compared to? Obviously the IDEX_XOFFSET is not the actual distance between toolheads. The VAOC routine moves the toolheads a specified distance and then compares where the nozzles are relative to that? So for whatever reason I'm guessing that relative distance is about .75mm different than what the software calculates. If the T1 endstop was out of position by .75mm along the X axis, the software would have the toolhead in a different place in X than it actually is relative to an assumed X max. I am not sure how you keep the endstop location out of play here. Granted that doesn't mean you don't keep it out of play, I am just not sure how you do it.
VAOC can measure the offset only behind the bed at one single spot. if you have a gantry skew then you will have such printing issues. VAOC can take a skew calibration into account, you jsut need to activate a profile for it in ratos
Well I read the new commissioning guide and when I went through the gantry check it was out on the right side by 3mm! So I have a badly skewed gantry. Prints great like that lol. Anyway I corrected the issue by loosening up the screws on the x gantry plates to the Y carriages, and also loosened up both Y linear rails and re-aligned everything. Now I have it all back together and the gantry is perfect in the back and front. Going through IS now and when that's good I will do the initial setup for VAOC over again and then check if the offset is correct. Report back when done.