worked fine for a few days and then disaster
The quick story is that I printed a number of things with my new Core One Plus without any obvious problems, but now, a few days later, the filament seems to be puffing up immediately after it's extruded and causing prints to be blobby. (More detail below.)
First, I am essentially brand new to 3D printing, so I could be making obvious errors and not realize it.
Anyway, I got my Core One Plus kit and assembled it without too much trouble. The first problem that I ran into was that during initial calibration my belt tension was so loose that it couldn't perform the basic X/Y calibration. I finally figured out that it needed to be tightened up enough to at least not slip.
Anyway, I finally got things calibrated seemingly correctly, and I was able to print the keychain, then a Benchy, then a (seemingly complex) articulated bear and a clearance tolerance test without much problem, before I moved in to a number of simple plate-like prints of my own design. The tolerance test printed hinges with clearances down to 0.10mm, and I was able to move all of them. The 0.10mm required a little breaking and is a little tight, but movable, but the 0.15mm moved without any problem. I was pretty pleased with this. This was all printed with PLA: the keychain and the Benchy with the sample orange that came with the kit, and the rest with Prusament "My Silverness" PLA blend.
A day or two went by and I thought I'd try some new things, but decided to print another Benchy to ensure that everything was working as expected before I started changing things. I didn't watch it print, and when I went to collect it, starting about halfway up, each layer was shifted to the "southeast" from the last. After a good deal of troubleshooting, I finally realized that the belt tension had somehow gotten much looser. I tried to retension it and I think it's okay now, though I am still very uncertain about it. I was able to print a Benchy again without the layer shifting, but certain parts of it are now lumpy and imprecise in a way that my previous Benchy print wasn't. I tried watching it print and something I noticed is that as it lays down a thread, there are times when the thread seems to puff up immediately after it's printed, so that when the extruder comes back around, it's actually pushing that previous thread back down. It seems like it was happening more in particular areas of the print, like when it's printing the outside edge, the points where there's a reasonably sharp curve is where it's happening most: the point of the bow and the aft starboard corner, mostly. And the smokestack looks like a lazy screw.
What is going wrong?
RE: worked fine for a few days and then disaster
Well, I think I figured it out. The first Benchy I printed, that came out fine, was using the "Benchy_Rules_0.4n_0.2mm_PLA_COREONE_14m.bgcode" file delivered on the included USB key, and I printed it with the included Orange PLA sample. The one that printed lumpy was printed with the same G-Code, but using "My Silverness" Prusament, which I guess has done different extrusion characteristics. I just now printed it again, but started from the STL and ran it through EasyPrint targeting the "My Silverness" filament and it printed just fine.
So I guess this is a learning experience for me that you can't necessarily expect the same G-Code to work for different filaments, even if the printer just thinks both are just "PLA".
How are you cleaning your build-sheet? How are you drying your filament?
Generally for problems like this where the file is known to print well we need pictures of the problem print including a picture of the underside.
but
As you are having problems with belt tension it's best to follow the standard advice for new machines and new built kits and seek one to one advice from Prusa Support via chat; you will need your printer's serial number.
Cheerio,