Successful calibration, Z-Live Adjusted, still no stick?
Hey there folks, my partner and I've been struggling with an issue over the past few weeks, and I'm starting to believe that the printer is trolling me.
After initial assembly, setup, calibration, etc. and several successful PLA, & PET-G prints we suddenly stopped getting bed adhesion. Of course, the first thing we tried was thoroughly cleaning the bed with isopropyl alcohol (%70), sadly no love.
Thinking we may have just been getting lucky and our calibration was actually off the whole time, we went through the process again, and then dialled the Z-adjust in further with the advice found in the Life Adjust Z Thread. This seemed to work for a couple of prints, in PLA, but PET-G would no longer print unless the process was slowed right down to under 15mm/s for the first layer, and even then it would be rough results.
Yesterday I did a full Calibrate XYZ, and Z-Adjust, that seemed to be working until I pressed the Auto-Home button at which point My Z-Axis jumped up by over 5mm (Yes, I'm aware that auto home will move the Z-Axis up to a safe distance from the bed, I'm talking about the 0 point here) I haven't replicated that but I'm a bit worried that there may be some instability somewhere that I won't be able to find.
Today, I again went through a full Calibrate XYZ, then Z-Adjust with paper, and further tweaked with the first layer cal print until my layer height was exactly .2mm ±.01 measured with digital callipers.
bed adhesion was good, so I tried printing a single layer 50x50mm square. No joy, the Prusa PLA doesn't stick to the bed even a little bit, everything just extrudes and smears around like the be is coated in grease, despite the thorough cleaning I mentioned. I've tried printing both my own sliced STLs, and the code provided on the original SD Card.
I've been using Slic3r PE, the latest available version from the website.
I've deleted and re-installed slic3r just incase there was a messed up setting inadvertently saved somewhere.
The results have been the same wether using the SD Card or Octoprint.
I've not tried any other slicers, as I think the default one would work the best.
Any advice on where to look for my next steps?
Re: Successful calibration, Z-Live Adjusted, still no stick?
70% IPA isn't good enough, Need to use 90%+
Re: Successful calibration, Z-Live Adjusted, still no stick?
70% IPA isn't good enough, Need to use 90%+
There's conflicting information about that. I've read both that it's no good, and that it's perfectly fine. I'll try %90, but do you have a source? Where should I look when that doesn't solve the problem?
Re: Successful calibration, Z-Live Adjusted, still no stick?
I use 99% IPA purchased from Amazon.
Do a good wash with soap and water every once in a while. After drying then use the IPA. Been working great for me.
Keep in mind that the IPA can work too well for PETG and you should do a final wash with Windex.
Check the manual that came with the printer as there is an entire section on how to handle various materials and precautions to take.
Re: Successful calibration, Z-Live Adjusted, still no stick?
have you done a pinda calibration and a temp calibration on the calibration menu?
“One does not simply use a picture as signature on Prusa forumsâ€
Re: Successful calibration, Z-Live Adjusted, still no stick?
Photos help diagnose problems.
I have always used 70% Ethanol on the PEI sheet and occasionally Acetone to refresh the stick. Very occasionally a quick wipe with soapy water.
And I have the original PEI sheets, 1 on an early Mk2 and one on a Mk1->Mk2->S upgrade.
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: Successful calibration, Z-Live Adjusted, still no stick?
I am having a very similar issue. I recently replaced the original PEI sheet on my MK2S because the prints were not longer sticking. The sheet was starting to feel slick and no amount of alcohol, nail cleaner, soap/water or Windex resolved. This is after hundreds of prints slicking perfectly for the last year.
The replacement sheet, purchased from Prusa, had a slick feel to it. After installation (time-consuming but went well), I performed the Z axis calibration. No luck, parts will not stick acceptably. I have gradually worked in a manual z offset of .5 mm with no apparent improvement. The replacement PEI just feels slick. I have tried cleaning it with alcohol and Windex too.
Re: Successful calibration, Z-Live Adjusted, still no stick?
just extra: but run a pinda calibration around the temperature you mostly use the printer at. i usually pinda cal at 240 degs.
are you running Temperature Cal on each print start up. if you enable it you get a 120 second delay as the pinda is placed near the bed and preheated then a 9 point bed height calibration is run.
you get a more accurate live Z. usually.
on my PEI sheet i prep with Isopropyl alcohol 100%, a sponge with green scotch brite on one side, and a micro mesh cloth(lint free).
i pour a little IPA on the bed and use the green scotch brite and just lightly scour the PEI sheet then mop up the IPA with the micro mesh cloth.
the scour roughs up the PEI surface a little and i get better adhesion along with getting all the Oils off with IPA.
for PETG i use windex and the same method to clean the PEI instead of IPA.
for Nylon i wet the sponge and use the yellow sponge side to remove the Glue residue.
ABS use the sponge scour to help remove the ABS juice with acetone.
then i just rinse the sponge in the sink to remove chemicals or glue.
if you haven't run a better LIVE Z test then the one Prusa gives you in the firmware then i would suggest you do. the usual test is make a 100mm x 100mm x .2mm test square use that to see if your live Z is too close or too far. most of my machines start at -.600 distance and then i adjust a little depending on the material and how it lays down on the bed. don't worry about feeling you are squishing too far you can compensate for elephant foot.
for my live Z tests i squeeze down so i don't see the lines from each pass on the bed just a nice smooth flat surface when i peel the test up. if you see smooth and then an area that looks like it is raised with the nozzle lines all wavey then the Live Z is too low.
if you see the nozzle lines clearly and they are clean and even then you are too high.
“One does not simply use a picture as signature on Prusa forumsâ€
Re: Successful calibration, Z-Live Adjusted, still no stick?
Alright John.v11, I'm officially a convert to high percentage Isopropyl, I didn't expect that change to work as well as it did, but I was pleasantly surprised. Thanks!
It turns out that that wasn't my only issue though, I discovered a few issues with my assembly while going through the standard troubleshooting again.
my X/Y skew was over .40º, when .25º is considered "severe" I knew I had to correct that, so I corrected the nuts on the threaded rods of the Y-axis to properly perpendicular on a successful calibration. Callipers helped, and I didn't own a pair when I did the build...
Once I fixed my skew, re-adjusted my PINDA Probe height, Calibrated, again adjusted Z, and thoroughly cleaned the bed with %99.9 Isopropyl I am now getting consistent PLA sticking with the first layer cal included with the firmware and with 5 50X0.2mm squares printed in the corners and centre of the bed.
No pictures because I totally forgot.