Introduction and setup basics:
I have a Folger Tech Prusa i3 2020 that I purchased in late January of 2016.
I have since upgraded the hotend and x-carriage to a machined version, and the heated bed to a 1/4" aluminum, machined, flycut, and lapped plate. Aside from that, few modifications have been made.
The hotend is the Bowden-type extruder. It's the top-listed E3D knockoff on Amazon (and should be easy to find if you're looking for it. Build photos and pictures can be found on my Instagram, @jrucksprojects.
I have printed PLA and ABS with this printer with no issues. It took a lot of debugging, but as of last week, I got beautiful ABS prints out of this. On my Instagram, they're the photos of the arm mounts. In person, there's little left to be desired. They're accurate dimensionally and required almost zero cleanup.
Problem:
Recently, I tried to print PETG and I haven't had ONE successful print with it.
A. I got frequent errors from this printer. It would struggle to reach the extruder temp. About halfway into the first layer, to halfway into the second layer, the extruder would jam or stop extruding. Some times, I would find that the extruder lost heat, other times I had no explanation. Out of code, and operating in the Repetier host print panel, I can extrude filament by hand and the extruder maintains temp easily.
B. For a short period, I could not connect to the printer. It did not show up, it was as if it wasn't connected. I wobbled every connection on the RAMPS board, and after 45 minutes, I got it to work again. The X axis was first to work, and after a restart and a reflash of the Marlin firmware, the rest happened to work.
C. After I got it working, I noticed erratic behavior from the Y axis. It didn't sound right. I checked the voltages on the stepper drivers, and a few of the drivers showed very high voltaged (4-5.5v). I adjusted accordingly. No drivers or motors seemed too hot. I had calibrated these drivers before, and cannot explain why they'd be fried.
Possible triggers of the problem:
I purchased eSun PETG 1.75mm filament to use with this full-metal hotend. This required higher temperatures than this printer is used to. I tried FOUR times to print a not-too-difficult print in PETG with various bed temperatures and a 250-265 degree C hotend temp. I settled on a 255-265 degree hotend temp, a 90 degree bed temp, a hefty coating of diluted Elmer's glue on the bed.
I noticed the printer struggled to reach these temps, but IMO the only real stresses on the hardware are on the MOSFETs powering the heated bed and extruder. Why am I having driver issues?
Question:
What should I replace?
What should I check?
Is there any other information needed to help diagnose this problem?
As I've said, any input, guesses, questions are welcome. I am really stuck here, there's a lot I don't know, but it's impossible for me to find the issue myself if I don't know where to look. All I have are potential symptoms and causes.
Thanks again, much appreciated.
-Jason