While out on our euro-trip the MK2.5 upgrade for my beloved Prusa printer came in. I had finally plowed through enough chores to get started on the upgrade when I realized you need to print everything first. I ordered this 6 months ago and could have easily lined up all the replacement parts by now. Oh well, shame on me for not reading ahead. They did include a 1/2kg spool of PETG to print everything with, so lets get that started.

Now I know my bed is shot, thats why I wanted this upgrade. It gives you a double sided spring steel printing bed. Still, I couldn’t get the first layer of Prusa supplied PETG to stick to save my life. This was my best attempt, and this was pretty bad.
I switched to some Push Plastic brand PETG that I had around and it initially looked golden. Soon though I ran into issues. There were z-layer striations in many of the prints like the nozzle was partially jamming. I thought some of the odd and difficult to print features were to blame and broke up the prints into smaller batches. These batches had problems too. I spent 2 days printing with different settings, cleaning out the nozzle, replacing the nozzle, taking everything apart, switching to PLA, and doing about 10 other things. All I did was get more frustrated and produce a pile of garbage.

I was incapable of producing small parts without error and big parts would completely jam before finishing. These were the most horrible frustrating times I have ever had with a printer. Even worse than my monoprice, and that is saying a lot!
I thought the hot end section was damaged, and on one of the tear downs to look for issues, I decided to give the extruder a rotate. I had checked its pin out with a multimeter, and inspected the wires for frays, but a single rotation by hand gave me the clue I needed. It was nearly impossible to turn.

Here is what the inside of a Prusa MK2 extruder motor looks like in case you ever wondered. The bearing on the left is fine, the one on the right is frozen solid. They are a smaller size than the 608 bearings I have around, and that most people use for projects. I ordered some to repair this unit, and contacted Prusa about getting a whole new extruder. If it isn’t too expensive I will eventually swap my repair job for a new unit.
The bearings will be in shortly, but I am dead in the water till then. Once repaired I will, hopefully, be able to finish printing all the upgrade parts, then I can have a whole new extruder setup and print surface. Until then, this is what my poor printer looks like. Never a good site. Nice use of my printed organizer tray. It keeps screws and bits separated and organized when you take something apart.














I have a poor solution to storing my yard tool batteries. I never developed a clear place for them, so they ended up piled onto the cart that holds all my drill press junk. That seems to be the story of my organizational life. Either make a place for something, or expect it to be awkward and always in the way.

