PS. I recommend replacing the 2 Phillips head bolts that hold the hotend in place with socket-head-capscrews (Allen bolts) – available at McMaster or Home Depot. Trying to worm out a stripped head is really annoying.
It would depend on which version of the printer you have. The Post-Kickstarter R1 came with an all-metal Hexagon hotend that is perfectly capable of printing PETG. PETG requires the same temperatures that ABS does, so if your ROBO is stated to handle ABS, it will handle PETG as well. Mine has no mods and prints PETG better than it prints ABS most of the time.
Be sure to blow out the dust with canned air, and I remove the hobbed bolt and attack it with a wire brush (or a file card or a razor blade) to get all the plastic out of the teeth. Mine kept doing that after ~4 hours, so I replaced my bolt with one from eBay and it seems much better (still not sure why). I find that a coat of WS2 lubricant on the hobbed bolt helps a lot – at least the shavings from the eventual jam come out more easily.
What I do on my robo R1+ is hest to about 190c, turn the gear as if you are loading into I see filament coming out of the nozzle then turn the gear counter clockwise until the filament literally pops out the top.
What I do on my robo R1+ is heat to about 190c, turn the gear as if you are loading into I see filament coming out of the nozzle then turn the gear counter clockwise until the filament literally pops out the top.
