Z probe/bed issues
When I go to run a print, it does its probing of the 9 bed points, but all three on the right side do not want to trigger the probe. Left and middle are fine - but it errors whenever it goes to the right. I've replaced the PINDA on my mk2s twice now and continue to have issues. It is definitely *not* the PINDA itself, because I can put a thin metal spatula (same thing I use to lift prints off the bed) flat on the bed when the probe hits those points, and it detects the spatula just fine - allowing me to continue to print. BUT the spatula itself is about 0.5mm thick and thus anything printing to the right of center is *wildly* off, leveling-wise.
Do I need to replace the bed? Can I superglue a few little circles of aluminum foil to the bed (inelegant, I know, but thinner than a spatula)? Any ideas?
Re: Z probe/bed issues
Why would you want to replace the bed?
There is something out of line here for a obviously working probe to miss the points.
Could be the frame askew, loose x-axis belt and/or pulley.
High friction in the x-axis or the probe to high or askew.
Bent/broken pinda bracket.
Or a combination of some of the above.
It also seems your printer fails at the bed leveling before a print.
Reset your printer and delete all calibration data (Display-menue).
(flashing the firmware at least would do no further harm)
Then run through the complete calibration process which most likely
will solve the problem, given there is nothing mechanical loose/askew....
Re: Z probe/bed issues
Well whatever spots are in the bed are no longer triggering the probe, and the probe has been replaced, so I figured next step would be replacing the bed.
Nothing is loose or askew - belts are properly tight, no extra friction anywhere, everything is perfectly level and square (checked and double-checked), no broken or bent brackets or anything. Prints *beautifully*, once it starts.
I've updated the firmware already but it still fails during calibration 90% of the time unless I put something metal under the probe on the right side when it goes to hit those three points.
Re: Z probe/bed issues
And still I would bet my ass it is not the bed.
One final check: Move the Pinda by hand over the points which do not trigger while mesh leveling
and check whether it switches or not.
I've updated the firmware already but it still fails during calibration 90% of the time unless I put something metal under the probe on the right side when it goes to hit those three points.
That is exactly what I tried to say.
The initial XYZ calibration besides others is used to verify the exact position of those points in the bed.
Those points are then approached directly for every mesh leveling before every print.
Moving/relocating the printer could alredy be well enough for some points not to trigger properly.
It in some post here is said, that even a complete XYZ calibration could fail if the old cal. data is not deleted manually.
This I can neither confirm or deny, no idea how the fimware exactly works but
for me that did the trick, once having had exactly the same problem as you now.
I could not imagine how those metallic cal. points in the bed suddenly should not be metallic anymore or even dissappear without any trace....
Re: Z probe/bed issues
Hey guys, was there ever a final solution to this issue? I'm having a similar problem. My printer has been running flawlessly for months (purchased Dec. 2017) and all of the sudden the three rightmost points are not being captured by the PINDA. My case may vary from rose.s however, in that it the PINDA 'touches' off on the first and second points but when it reaches the third point it very clearly moves in the +Z direction and fails. I've reinstalled the most up-to-date firmware and checked all of my cables and terminals (everything appears fine). The PINDA appears to be working properly (LED goes out when I place metal under it).
When I reinstalled the firmware I started the calibration process and passed the self-test. When performing the x,y,z calibration the extruder assembly lowered but stopped about 30mm from the bed and started the 'point search'. It went through four iterations and lowered much closer to the bed but still about 10mm from normal (multiple attempts with similar results).
In my mind this does not appear to be a PINDA or Bed issue as I can clearly see that the components do not come close enough for inductive interference but I have a new spare PINDA I may install just to eliminate it.
Not sure how to proceed here; any assistance would be appreciated!!
Re: Z probe/bed issues
OK, there are 2 or 3 possibilities:
1. You need to try lowering the probe (not a lot)
2. Your probe cable is broken internally
3. You have something (filament string) wrapped around an axis pulley, under the belt
You can test the probe as follows:
Move the extruder to a position where calibration fails, a few mm above the bed
On the LCD, select to "show End Stops"
Place the tip of a screwdriver under the probe. Both the probe light and the LCD Z state should change - if neither or only 1 state changes, then you have a faulty cable.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Z probe/bed issues
Perfect! So as I started to check the PINDA as you described I noticed the LED would go out once the X axis passed the middle of the bed (can't believe I didn't notice this prior). I noticed a kink in the blue cable just past the termination point (might be able to repair it for another spare PINDA). I replaced with the new PINDA and am running the calibration without issue thus far! I'm wondering if there is a better way to secure the cable bundle into the Rambo housing rather than just cable ties and wrap to help prevent this from happening in the future. I'll search the forums for solutions. Thanks for all of you help!
Re: Z probe/bed issues
Cable usually breaks just at the rear of the extruder; the "S" upgrade was developed to prevent this happening.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…