Bumped PINDA sensor while lifting metal sheet  

RE: Bumped PINDA sensor while lifting metal sheet

PINDA does not move easily in its mount.

Try printing a calibration square. If it is good - you are fine.

RE: Bumped PINDA sensor while lifting metal sheet

Posted by: @robert-rmm200

PINDA does not move easily in its mount.

Try printing a calibration square. If it is good - you are fine.

Thanks, I will give that a try. I was concerned because z-axis is being adjusted by micrometers and a bump could move it 100 micrometers and I wouldn't see that, maybe? 

RE: Bumped PINDA sensor while lifting metal sheet

Well a safety check would be to put a piece of paper on your bed. Lower Z through the panel to your Z setting.

See how the paper feels. If the nozzle digs in, run calibrate followed by Live Z adjust. Otherwise, just print that calibration square.

RE: Bumped PINDA sensor while lifting metal sheet

It looked okay, still continually adjusting z-level though. I printed that large 3inch square but was never able to get it perfectly smooth. There was lots of ridging if I run my finger across it.

RE: Bumped PINDA sensor while lifting metal sheet

Post a picture to the forum for the experts to look at.  It is possible to go too low with live-Z as well.  The sweet spot is actually pretty narrow.  Also, make certain that you have enabled 7x7 mesh leveling on the printer to better accommodate minor warping of the heatbed.

Regards,

Steve

RE: Bumped PINDA sensor while lifting metal sheet

Hi Steve, I uploaded some photos here: https://imgur.com/a/1MxafIB. The bottom right corner I started around -0.950 and saw lots of gaps, slowly increased so that in the middle about -1.050, then set to -1.150 from middle to end. I also realized after printing that mesh leveling was only at 3x3, so I changed to 7x7 and I'll print with that based on what you recommend.

You asked in my other thread about the frog about what filament I was using. It was printed with Hatchbox PLA, and this z-level calibration was done with the same filament. I didn't want to burn "good" filament first. But I assume each filament type needs to be calibrated separately or not?

Thanks.

RE: Bumped PINDA sensor while lifting metal sheet

You set Z for each sheet (smooth or textured).

You have to set it again for any mechanical change (new nozzle, etc).

It should be fine for every filament - unless you see reason to change it. I have never changed mine for a different filament.

RE: Bumped PINDA sensor while lifting metal sheet

Xilex,

I took a look at your posted photos (to anyone else who is trying to look but failing there is an extra period captured in the URL at the end that must be deleted) and judging by the topside appearance I agree that -0.950 was too high for your printer.  However, your next step to -1.050 was already too low, the blobs and bulges you see are filament being squeezed away from the nozzle.  The giveaway however is at the ends of the runs where you can clearly see the nozzle has dug into the filament and created a trench.

I would begin with setting the machine to 7x7 mesh leveling and then begin your first layer calibration again starting with a value of around -0.970 for your setup and this sheet and work from there.  You are looking for a nice "squish" to the filament but there should be no nozzle marks.  If you are using the g-code for the coupon from the https://forum.prusa3d.com/forum/original-prusa-i3-mk3s-mk3-assembly-and-first-prints-troubleshooting/life-adjust-z-my-way/ post and have the means to measure it the coupon should be 0.2mm thick when your live-Z is correct.  

To put numbers to my "sweet spot" comment above, the difference between acceptable, too high and too low on my machine is a range of about 0.016 mm! I found that for my old eye a flashlight and a magnifying glass were useful when I was getting close.  If you are measuring you would also discover that the thickness is only a minimum at the optimal Z.  If you get too low the nozzle pushes up the filament and the measure thickness begins to increase again.

Good luck and we'll be on the lookout for further test prints.

Regards,

Steve

RE: Bumped PINDA sensor while lifting metal sheet

@steve_g

Thanks for the replies and explanations, Steve. I ended up contacting Prusa support after showing them some additional prints while trying to figure out the correct live-Z. They sent me something to test print that drew squares at corners and centers ( https://imgur.com/a/MOnqlfK ). And concluded right side of bed is higher than left, so need to adjust that then figure out the live-Z. I'll do this later this week.

Ya, even with all the photographs it is hard for me to tell what is correct and what is not for first layer. It's obvious when nozzle is too high because gaps are present. But it's difficult for me to tell what it means when it is too low. Blobs/globs, trenches, like you described is helpful. described it well, too, showing good/high/low up close.