Now that my group buy UGC-136 teleprinter is working, I am starting to use it and it works great. But as I use it, I have been having some trouble with the group 3d printed printer cartridge. The problem has been that the ribbon doesn't always advance. When it stalls, the print gets lighter and lighter and eventually doesn't print at all. I started investigating and it seems that the friction in the ribbon path can stall the ribbon, The solution is to reduce the friction, but how?

The solution that I found to work is to wrap PTFE fiberglass tape over the places where the ribbon makes a 90 degree or higher wrap. Once tape is applied in these areas, the ribbon advances easily and the print out is sharp and uniform. The PTFE tape I used was on hand for another project. A link to it on Amazon is here: https://a.co/d/0htbFmpz You certainly don't need the 3" width that purchased

I have done this to one cartridge and so far, so good. The tape seems to stick well if terminated from where the ribbon rubs on it. I think for the next cartridge I will line the entire ribbon path with the low friction tape. When I retrofitted the cartridge with tape, I thought it best to remove ink that had rubbed off onto the plastic to improve adhesion. I found that acetone worked pretty good and did not melt the cartridge.