Z-Axis Crash into Bed  

Re: Z-Axis Crash into Bed

Dominique,

Sounds like the height of where you have your PINDA mounted is way out of whack. The PINDA needs to be slightly higher than the nozzle but not too high so the nozzle touches the bed before the PINDA triggers. Check the build manual again for a hopefully working starting point, here's the picture from the manual in question:

Do a full re-calibration. At the beginning of the re-calibration when it asks you to raise the extrude all the way make sure it is well and truly up there, keep going till it starts skipping some steps (the rattling occurs).

Re: Z-Axis Crash into Bed

Thanks for this answer, but I don't understand how it's help in my case.

I started with the nozzle lower than the bed. After each crash into the bed, I screw down the nozzle. In the actual configuration the PINDA probe is lower than the bed. I don't undestand why, at the tests, the probe touch the bed.

Yes it's a problem for the next step but I must solve this one before.

Dominique

Re: Z-Axis Crash into Bed

I started with the nozzle lower than the bed.

I guess you meant nozzle lower than the PINDA. Ok, that's correct, that's how it needs to be. But the PINDA can't be too high up either. That's why I sent you the picture from the build manual yesterday, that's about where the PINDA should be located for a first attempt.

If the PINDA is too far up, calibration will fail or the nozzle will hit the bed because the PINDA with its limited range didn't see the bed until it is too late. If PINDA is too far down you won't be able to print as the pinda will slam into your printed object all the time.

After each crash into the bed, I screw down the nozzle.

The nozzle gets tightened firmly into the heater block and that's it. You screw down the PINDA probe...

In the actual configuration the PINDA probe is lower than the bed.

Bed? The PINDA might be lower than the nozzle, but that would be wrong. The PINDA *must* be be slightly higher than the nozzle.

I don't undestand why, at the tests, the probe touch the bed.

The PINDA probe touching the bed is very odd, indeed.

First: if PINDA probe hits the bed before the nozzle hits the bed, then the PINDA is way too low. See above. That's one part of problem and needs to be fixed by raising the PINDA .

In addition to that, we have a second problem:

For the PINDA to actually hit the bed, there are a few possible reasons:

a) the PINDA is broken. Since you wrote earlier that it did detect a metal screwdriver, i guess we could have some broken wire or a lose connector that works at certain positions only, doesn't work when the cable get's bent. I guess grab that screwdriver again and start wiggling / bending the cables to see what happens

b) I never found the video you mentioned but i guess we're talking the first spot during calibration. If the whole printer is so far misaligned that the PINDA misses the metal inlay it will continue to go down trying to find the spot until whatever is the lowest point will crash into the bed. The position of the first spot (front left corner) is marked with a faint circle on the bed. Is the PINDA inside that circle when it starts probing?

c) I guess there could also be a problem with moving the bed or X-Axis and therefore it cannot properly reach the spot. Maybe lose belts, slipping pulleys, motors skipping, wire bundle in the back blocking movement, something like that.

That's about all I can think of. Hopefully this will get you on the right track for finding whats going wrong.

Maybe upload a video of what's happening to Youtube or some place like that?

Re: Z-Axis Crash into Bed

Today use a différent approche. I launch the Z axes calibration and look a the PINDA probe ligth (if it switch off if it's near the print bed) and ... it works !!! No more carsh in the printbed. I made several test because the prod was to mutch down and when the nozzle is near of the print bed surface I launch the last Z axis callibration again and I have the same problem that I had at the beging 👿

Is it something to know with the PINDA probe? I have done the loop from the manual.

Thanks
Dominique