Lost in Z translation - late first layer troubles
Hello there,
After days of disstress, forum reading and printer check I am not able to figure my issue by myself, which really annoys me...
Issue: impossible to have a correct first layer, impossible to print anything correctly. The first layer does not stick correctly even with some glue, moreover it event seems to drag out some filament on some points
Context: I have my prusa i3 mk3 since 1.5 years approximately using it a few times a month, usually to print small mechanical parts designed by myself but also a few other toys. Mainly PETG for my parts and PLA for other stuff. Still have the satandard extruder, and an upgraded firmware corresponding to my hardware (but no change on these points between flawless work and horrible current issues).
Explanations:
After maybe a longer than usual pause (maybe 1.5/2 months) without printing, I had a need to print a part for my bike hanger. Designed it on solidworks and started to print it (no change in printer hardware or software or anything). Firts layer catastrophic after the few first centimeters.
I told myself "no problem, probably just to check first layer height". First layer wizzard with PLA horrible, impossible to make it work. So I told myself probably bigger defect. So I adjusted the nozzle height and PINDA (nozzle at the level of a paper sheet, PINDA a millimeter or two other) redo the first layer wizzard, but still difficult to have a correct results the square turns on the right of the PEI sheets were inconsistent.
As I had a new PEI sheet in stock I changed it, redone the all process still no success, bad sticking of first layer, impossible to have a good first layer wizzard.
So I decided to try a new nozzle, check competely the printer (has anything moved a rail, a linear bearing... nothing), redo the whole calibration wozzard (printer is perfecly square).
So now I am totally lost, I do not know what to check or try to have a good first layer with my prints and/or with the first layer wizzard.
What is frustating is that I have had first layer height issues (like anyone else I guess), but usually with method and starting with the approximate height of a sheet of paper you usually manage to solve the issue. Today it is impossible...
If anyone has clues I am open to try as I don't know what to do with myself 😛
Thanks,
RE: Lost in Z translation - late first layer troubles
You have probably read in other forum posts about your problems, and the answers are always the same ....
1. Clean the bed with detergent and warm water, then wipe with paper, do not touch the surface with your fingers.
2. Adjust the Z-level so that the first layer is smooth and without any gaps in the surface.
Note that a well-calibrated first layer is only 0.2 mm thick. It is the same thickness as 2 regular office papers.
Bear MK3 with Bondtech extruder
RE: Lost in Z translation - late first layer troubles
Thnaks for your answer.
I carrefuly cleaned the PEI plate.
I adjusted to the height of two paper sheets (good advice thanks as I was usually starting with one).
I then launched the first layer wizard with PLA --> good result (long time no see, thanks)
I then relaunched my part in PETG and finished rapidly in a mess
I even tried to print it with a raft, but still no good adhesion.
The nozzle seems to scratch the first layer
So thank you it is better, but still nothing close to the previous flawless prints I was used to.
RE: Lost in Z translation - late first layer troubles
I am not familiar with any filament wizards - but I find myself using the LiveZ adjustment whenever the first layer looks to be dragging filament or starting to peel at the ends of interface lines laid down for things like Supports.
When I see the print head struggling to stick a bead to the bed - usually shows up at the Skirt painting step - be quick and use the knob on your control panel to scroll down (I think is only one notch) - Live Z adjust.
The more negative the # (for my smooth PEI sheet, PLA is good at -.500 and PETG sometimes needs to go down to -.520 or so before the curlies stop lifting up at the edges of the print.
My suggestion is to know your live Z ranges for the sheets you print on - smooth sheet is not as thick as textured sheet, so textured sheet will require a very different live Z - which is why the control panel lets you set up sheet profiles so you can have a stored live Z value for any named sheet type.
Also, get used to adjusting live Z while the print is starting. You seem to be relying on positioning your zero around two sheets of paper thick - but to me that's a rough cut, and live Z is where you get your biscuits from.
RE: Lost in Z translation - late first layer troubles
Yeah I started with two sheets height but as the first layer wizard was good I did not feel any adjustment needed.
I always print on smooth sheet.
Maybe I can try lowering it a bit with the switch to PETG.
RE: Lost in Z translation - late first layer troubles
A question about your last picture. Does that show the bottom of your detail, the first layer?
If it is the first layer, then my question is whether there should be such wide grooves at the bottom?
Or is your gcode so crazy created that what would have been a smooth and fine layer has become sparse ribs? Or is it something else that has gone wrong with your gcode?
Bear MK3 with Bondtech extruder
RE: Lost in Z translation - late first layer troubles
Hello,
Yes the last picture is the first layer of my part printed with a raft.
Of course the first layer is normally not like that. But usually making a raft is easier for good sticking.
RE: Lost in Z translation - late first layer troubles
Do recommend you use live Z instead of sheets of paper guess method. Live z uses the knob on your control panel to adjust the head-to-bed spacing in real time during a print.
RE: Lost in Z translation - late first layer troubles
Petg should stick to good to a pei sheet!!!!!
If you use a pei sheet for petg, you should use window cleaner on the bed(or glue tsick), so petg does not stick to much, you will damage your pei bed.
1. Clean bed with dish soap, use hot water , use a lot of water, and nothing else, do this several times.
2. Make a 100% first layer, this is needed for sticking(also cleaning is important).
If your first layer does not work, print a few cubes over the whole bed, start the z to high and make every cube lower, then you find the good height, I do this also because I go sometimes the wrong way with z adjustment.