Prusa logo prints but nothing else
I hope this isn't considered a duplicate but apart from very broad "first print problems" I didn't see anything else that quite matched.
I have a newly build kit i3mk3. Calibration wizard succeeds without issues or surprises.
My first-layer calibration landed me with a z level adjustment of -0.875. Anything lower leads to a flat-like-paper first layer instead of the "slightly squished" recommended by the manual and videos. The first-layer calibration produces a nice square-corner zig-zag that passes the "finger-drag" test for adhesion.
Moving on to "print from SD card" I can print the Prusa logo with reasonable results. By "reasonable" I mean that it looks perfect from the top although once removed and examining the back-side, there are occasionally slight indications of lifting at one of the corners. Not a specific one, just one or sometimes two spots somewhere on the bottom that look less that 100% perfect to a perfectionist.
So far, so good, until I try to print anything else.
Attempting to print 3DBenchy looks fine for the first 3-4mm of height and then it detaches completely and the bottom of the boat is dragged around the print bed by the nozzle.
Attempting to print the batman battarang just results in a tangled ball of string at the very first layer.
Going back and printing the Prusa logo produces the same reasonable results as above.
All of the above results are reproducible. First-layer zig-zag looks good. Prusa logo looks reasonably good. Anything else is a disaster.
I'm using 91% IPA between attempts. I haven't attempted acetone yet on the assumption that since this is a brand-spanking-new PEI sheet the probably is more likely calibration or user related. I tried lowering the z-adjustment but that resulted in pancake flat first layer with no other discernible difference in print results, so based on the calibration instructions I went back to -0.875. Based on some suggestions found online, I tried lowering the bed temperature by about 5 degrees but didn't notice any difference. I also tried a brand-new package of Haribo bears, which provided some sweet, sweet hope, but no difference in the print results.
I'm sure I'm making some obvious newbie mistake but I can't quite figure out what. Any help would be greatly appreciated.
Thanks.
Re: Prusa logo prints but nothing else
Your 1st layer Z is probably still too far off the bed. Lower live Z a bit more. That should squish the 1st layer down enough adhesion. That first test layer should come out like a continuous sheet of paper with a tiny bit of grooving on the top. If it is still separately stringy, you're definitely too high for 1st layer Z height.
Re: Prusa logo prints but nothing else
Yep, sure enough. If I ignore the directions for first-layer calibration and go full-on paper-flat first layer it seems to work. Apart from more speghetti strings across gaps, I was able to print the things that were failing before, including a fairly respectable 3DBenchy.
So first and foremost: Thank you!
Secondly... just so I understand better... why?? I mean I'm clearly well past the "slightly squished" diagrammed in the manual and certainly it looks like I'm well into "too low" territory, but at the end result it works so much better. So, assuming that the instructions are not wrong, is there some other factor being glossed over that explains the difference? And is there some better way to calibrate this besides just a lot of trial-and-error?
Thanks again!
Re: Prusa logo prints but nothing else
Try the "life adjust" Live-Z calibration method. It's much easier to use and understand than the on-board routine. I've seen unconfirmed reports that you do need to complete the on-board routine at least once (which you have) in order to set a flag to avoid drifting, but after that, the technique described in that thread is a winner.
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