Prusa i3 MK3: Can't get a good first layer calibration print
Hi,
I just assembled my printer. Went through the calibration procedure and I cannot get the first layer calibration print to work.
I am using PLA and a textured sheet.
Attached is a photo, but the issues are:
1. the lines are not at right angles,
2. the material sometimes is not sticking to the heat bed.
3. When it prints the block of PLA at the end it is getting clogged on the print head, or warping.
I have been through this calibration so many times and nothing I am doing is making a difference. I have tried adjusting the head up and down within the -2mm limit - no difference. I have cleaned the heat bed with alcohol to help it stick, and recalibrated about 5 times.
Where do I start to diagnose this?
RE: Prusa i3 MK3: Can't get a good first layer calibration print
PLA sticks not good to the powder(textured) coated bed. If you have petg use this to learn the printer.
The not straight lines is because the nozzle is to high and/or the filament is not sticking.
Most important for printing is:
1. Clean bed, use dish soap with hot water, wash 3 times so all dirt is gone, alcohol does not clean all dirt, if you use alcohol , use a lot .
If you print pla, always clean with dish soap. If you print petg, you can use alcohol a few times, then use dish soap again.
If you wash a sheet, dry it and heat ip up, it needs to be dry, but if do not dry, it will rust.
Do not touch bed with your fingers it will destroy sticking to the bed.
2. First layer calibration is very important. Powder coated bed, you need to go a little lower then a pei sheet.
here is a movie on how to.
Both settings are needed for a good sticking to the bed.
Pla printing on powder coated bed, us a big brim attach to model, so the model has a big footprint to the bed.
If you get this wrong, the model will detach and stick to nozzle, and you get a big ball of filament sticking to the nozzle.
RE: Prusa i3 MK3: Can't get a good first layer calibration print
brim aatache to model,
Go to printer settings,
skirt and brim,
then : distance from object, fill in 0
then: brim width: 8 mm
Now model is bigger and more area is touching the bed.
RE: Prusa i3 MK3: Can't get a good first layer calibration print
I spent a long time with live Z when I first got mine and it can be frustrating but you'll get there in the end and then later wonder why it seemed so difficult!
Your PINDA sensor might be too high and hence the max Z adjustment isn't enough to get the nozzle close enough to the bed.
Also give up with the Prusa adjustment print and use a larger object thats much easier to see, theres a good thread here:
RE: Prusa i3 MK3: Can't get a good first layer calibration print
Printing pla with powder coated sheet, 10 degrees higher bed temps is better for sticking.
RE: Prusa i3 MK3: Can't get a good first layer calibration print
For PLA on textured sheet,
extra you could do:
Print first layer the nozzle with a higher temperature 5 or 10 higher.
RE: Prusa i3 MK3: Can't get a good first layer calibration print
Thank you everyone!
I can't reply to everyone so I am posting as a new response.
There are a bunch of options to try here and I'll experiment with everyone's recommendation. But suffice to say, I changed the sheet to the smooth sheet and recalibrated and it worked perfectly. I even printed a batman throwing star from the SD Card! 🙂 So the lesson is to study which plastics are best to print on which sheets.
The lines on the "first layer print calibration" were extremely thin - so I suspect that is what @peter-m-3 was talking about.
So now I have it working the learning begins. 😀
Thanks again
Bryan
RE: Prusa i3 MK3: Can't get a good first layer calibration print
PLA does work on powder coated sheet, but it could fail fast, and is difficult to adjust.
You need to work with every print clean with dish soap, an use a big brim with smaller parts, and first layer calibration a little lower.
My idea is if the powder coated sheet is a little older it will, it wil stick better, i am using pla on the powder coated sheet(just started using this sheet after a few years).
Same for the pei sheet , wen is gets older it will stick better.
Nice about the powder coated sheet, the release is very good after printing wen it is cold.
For both sheet let it cool down, the release the model, if you do not wait you will destroy the sheet.(use a mobile fan for this)
RE: Prusa i3 MK3: Can't get a good first layer calibration print
@peter-m-3
Thanks. I got it working by changing the sheet (my result is below). I like your test print, I'll make up one that big so I can play with the live adjustment. How did you get each run to be so thick?