I’m writing a couple of notes to my future self about this printer.
This morning, I was trying to to swap out the pink filament with new white filament that I picked up on Amazon. The filament was completely stuck, I couldn’t unload or load or do much of anything with it. I found great GitHub repo for MOD-t utilities, and tried running the clean nozzle tool. (There’s a config file for Slic3r, a popular modeling tool for 3D printing. There are some calibration files, old firmware, and a clean nozzle utility.) That bought me a bit of pink filament dripping out of the nozzle. However, after some additional searching, I found this Google Group for the MOD-t, and on it, there was a really helpful post entitled “Clearing Filament Jam Without Opening MOD-t”. Basically, it said that the jam may be living above the nozzle, and if that’s the case, then what you can do is remove the hot end (nozzle), heat up the nut (with a soldering iron or something), and pull the jammed filament out.
I used tweezers to hold the filament inside the nut, and needle nose pliers to hold the tweezers. Then I heated up both the tweezers and the nut, and was able to pull the jammed bit of filament out. After that, I replaced the hot end, loaded the new filament, and was back in business.
Future self - if this happens again, try the above solution!