bed leveling seems ok but not...what a nightmare

[skAt]

Hi all ! I've seen a lot of topics about the bed leveling problems and know i think it's time to add mine !

I'll try to be as clear as possible: everything was ok for my Max V2 since i got my printer (in june if i remember right). Mounting it was cool, the first calibration was hard but ok at least, and i've print about 1.5km of filament until last week.

I wanted to do a new calibration after having move the printer, just in case something moved. So i made it, everything looked ok until i start a new print (calibration test with a big circle).
THE HOTEND STARTS TOO HIGH FROM THE PRINT BED AND THEN GO LOWER AND LOWER UNTIL I PUSH AGAINST THE BED. AND THE GO BACK TOO HIGH !!

If i'm right, some people had this kind of issue.

Now i'll explain where i think the problem "comes from". When i launch my calibration macros, just when the carriages start to lower, something happens like missing steps or something blocking (maybe be mechanical issue).
The interesting point for me is that it happens only for the macros X, Y and Z towers ! When i go to the center of the bed: everything is ok.

I think that this little thing that happen turn the calibration "wrong", even if at the end i'm at the right height for each positions including the middle point. Then when i start to print something, it's like my bed has an angle of some degrees.

Please tell me that one of you has some magic trick to fix this !

I've spend 4 evening this week trying to fix this with a lot of test, and i'm out of ideas.

[Holy1]

Just go back to the manual and start the calibration from scratch . Be patient and do each step again. You may have missed something without realizing it as you said it worked OK before you attempted to calibrate again.

[skAt]

I've done again and again the calibration. I can tell you that when I launch my 4 macros, I'm at the right height from the bed.
It's not a calibration method problem, it's something else for sure.
But thanks for the advice ah ah

[stonewater]

so is your delta radius correct? when your nozzle is at the perimeter of the bed BETWEEN towers is it the same Z height?

Tom C

[skAt]

Yes yes. I've also changed the macros to come close to the towers.
I can tell for sure that the calibration is done the right way according to the manual.
Is for sure something with the "missing steps" when I use the macros.

[626Pilot]

What's your stepper motor current set to?
How tight are the belts?
Are the stepper wires braided, or are they just flat?
Are any wires laying across the stepper wires, or laying across the endstop wires? They should be protected from electromagnetic interference as much as possible. (That's why it's best to braid them, and keep them as far from other wires as possible.)
When you built the printer, did you do the step of making sure all the towers are exactly the same height (go around with a yardstick or meter-stick to ensure)?
If you can get something like this, use it to measure the vertical tower angles - any deviation from 90 degrees is a problem.

If none of that works, you can try my Smoothie fork (link in sig) but that requires buying a new controller and it's not cheap. I had problems similar to yours, so I fixed the printer in software.

[jason128]

Yes yes. I've also changed the macros to come close to the towers.
I can tell for sure that the calibration is done the right way according to the manual.
Is for sure something with the "missing steps" when I use the macros.

making it closer to the towers may be adding to your pain- i would start with what the manual suggests- as you get closer to edge, it all gets much more sensitive.
i chased similar problems and eventually found the delta arm play was enough to mess with the calibration. adding rubber bands like the trick lazer arms sorted this.

Is it consistent around the perimeter- i.e are all towers out the same amount? if so, it sounds like a delta radius issue.

I also forgot to home every time between when calibrating- this stumped me for a few days.

[ZakRabbit]

At what speed do you have the macros running? Both rapid and feed can cause missed steps as you approach horizontal on any given arm as I understand it.