how to test the probe  

Re: how to test the probe

go to the calibration menue ans choose "Show end stops" while the extruder is located a few cm above the printbed. when you now put some metal under the pinda probe, the Z reading should change form 0 to 1.

further questions: is the dim, red light at the rim of the probe lit ? and if so: what happens if you put some metal under the tip of the probe (does it go off ?).

Re: how to test the probe

Yes the Z goes from 0 to 1 which means that the port is working. Thanks for the tip! Also the red light goes off when I put metal under it.

Still it does not trigger when calibrating. Any other ideas?

Re: how to test the probe

Yes the Z goes from 0 to 1 which means that the port is working. Thanks for the tip! Also the red light goes off when I put metal under it.

Still it does not trigger when calibrating. Any other ideas?

what's the height difference between the tip of the nozzle and the tip of the probe ?
should be about 0.7 or 0.8mm. but some probes are quite deaf, so you need to go for 0.5mm.

furhtermore: go to the calibration menue and choose "Auto home" first. your printhed then should move to the front left corner and the tip of the probe should stay exactly inside the circle at the printbed.
now go to the calibration: "Show end stops" menue again. does the Z value show a 1 there ? if not: what if you squeeze the printbed a little bit upwards with your fingers ?

Re: how to test the probe

Yes the Z goes from 0 to 1 which means that the port is working. Thanks for the tip! Also the red light goes off when I put metal under it.

Still it does not trigger when calibrating. Any other ideas?

what's the height difference between the tip of the nozzle and the tip of the probe ?
should be about 0.7 or 0.8mm. but some probes are quite deaf, so you need to go for 0.5mm.

furhtermore: go to the calibration menue and choose "Auto home" first. your printhed then should move to the front left corner and the tip of the probe should stay exactly inside the circle at the printbed.
now go to the calibration: "Show end stops" menue again. does the Z value show a 1 there ? if not: what if you squeeze the printbed a little bit upwards with your fingers ?

Don't want to create confusion, but I may had the same experience.

During two months, no issue at all with calibration. Then, point 9 of 9 started to fail, nozzle going to bed. Was OK after a restart of the print.
Recently, everything failed, XYZ calibration had nozzle going to bed during 4 points phase.

Finally, I had to lower a little bit the PINDA. That's stange knowing I used fillet glue on PINDA thread and checked the distance. It's like PINDA lost sensitivity.

Initially, my live Z was -0.160. Know, it's -0.380

Perhaps one idea: the ABS support of the PINDA seems to have a very low distortion. May be the PINDA is no longer completely vertical.

Re: how to test the probe

... It's like PINDA lost sensitivity...
meanwhile i encountered that the sensitivity of the p.i.n.d.a. probe is a function of it's supply voltage.
so if the +5V Vcc supply voltage at your rambo board is changing a little bit, you'll need to readjust the first layer.
0.1V difference may - depending on your working point - cause a deviation of up to 200µm.

so if you "steal" some power from your system to feed a hungry raspberry pi, or if you use a toshiba flashair sd-card (which requires much more power than a ordinary sd-card).... or even when some of the components are aging (or deteriorating) and the voltage changes a little bit (even within the specification of the voltage regulator), you may encounter changes in the sensitivity of the probe.

by the way, that's the reason why i've used a high-precision circuit to power the p.i.n.d.a. at my own i3 mk2 clone.

Re: how to test the probe

... It's like PINDA lost sensitivity...
meanwhile i encountered that the sensitivity of the p.i.n.d.a. probe is a function of it's supply voltage.
so if the +5V Vcc supply voltage at your rambo board is changing a little bit, you'll need to readjust the first layer.
0.1V difference may - depending on your working point - cause a deviation of up to 200µm.

so if you "steal" some power from your system to feed a hungry raspberry pi, or if you use a toshiba flashair sd-card (which requires much more power than a ordinary sd-card).... or even when some of the components are aging (or deteriorating) and the voltage changes a little bit (even within the specification of the voltage regulator), you may encounter changes in the sensitivity of the probe.

by the way, that's the reason why i've used a high-precision circuit to power the p.i.n.d.a. at my own i3 mk2 clone.

Although I didn't use the power supply for something else (Ouf!), that's indeed interesting to know. Thanks for the Tip.
But it's not exactly what I meant, because the change was "sudden" and I had to slighty lower the PINDA in order to have success on calibration without scratching the PEI. And nothing else was changed...
My theory is that PINDA is OK in a certain range that Prusa guys may "document". Live Z between (let's say) 0 and -0.200 are risky. Sometimes working, sometimes not.

Re: how to test the probe

Thanks for the advice. I lowered the probe significantly and it does calibrate.. It is much lower than the old one. It is a hair above the bed. When I printed the v2calibration the probe was scraping the top of the printed layers. Any tips for measuring the distance between the nozzle and probe?
When I get a few minutes I will double check that the probe is vertical. I dont know what else could cause lower sensitivity. I am not doing anything funky with the power supply. My new printed part had some layer shifting. I figured the worst that could happen with thatis the print would be a little off. Could that have caused probe issues?

Re: how to test the probe

Hey,

I assembled my printer 3 days ago and still didn't get it to work cause of (what i think is a probe problem) I followed the steps above to test the probe, and ran into a strange problem. Turns out that my probe is always showing Z1, also when its all the way up. And testing it with something metal doesn't do anything. (no light and no change in the number)

When i do ''auto home'' it doesn't chance anything in the height, cause of what i think it triggers the probe directly when its calibrating? always Z1.

The other end-stops work perfect, shows a solid 1 when i press them.

When i do any calibration it looks like the Z is just not working correctly, while the others are.

Also checked the manual wich doesn't really help me with this problem. checked that everything can move freely. didnt zip-tie to much and check the wiring a couple of times. it hasn't been connected in any wrong way.

I have no idea what to do now. i didn't get any calibration right cause of the Z acting weird 🙁 . it just goes all over the place, and everytime its in a different location cause it mostly won't go down after it goes up. (gets triggered directly?)

Does anyone can give me some tips or what i should do now?

Thanks in advance!

Lucien Boeijenga

Re: how to test the probe

..Does anyone can give me some tips or what i should do now?..

if the problem still persists after you've checked the cabling and the orientation of the connector (at the correct position), there are only two options left:

1st -> the probe always triggers because of some metal parts near the tip of the probe.
2nd -> the probe is defective.

if you've got a MK2S check that the tip of the probe is not to close to the m3 square nuts and the screws of the carrier bracket and make sure, that the square nut and the screws are not accidentally magnetized (maybe through a well magnetized hex-wrench). btw. i always had some concerns with this new mk2s design for the pinda holder.

furthermore check the orientation of the heater block. if it is assembled the wrong way, it might trigger the probe permantently as well.

😈 i remember a user who nearly ran mad with the same a problem (probe alway triggered)... until he noticed that there was a small piece of magnetic debris sticking at his probe.

➡ if it turns out that the probe simply always trigger, even if there is no metal nearby -> report your problem through the chat at the prusa shop. i'll assume that they'll send you a replacement part.