Solved Tolerances on the extruder feed neck? PCTPE

The hexagon hotend has a nominal diameter of 1.82 mm for the heat break, any type of filament that expands when heated like PLA does may cause clogging. I am not familiar with PCTPE myself, but it is advertised as an easier to print flexible filament. I would assume it is much more flexible and compressible than ABS. That could be the sole cause of your issues right there. Without modification the Robo is simply not designed to print flexible materials well or even at all.

 

Most filaments we buy may not be as round as you may think they are or should be. They tend to be slightly ovalized. This fact may make it harder to use one filament over another depending on how much it is ovalized. The 1.75 mm diameter is not a guarantee of a specific profile but rather what would be call nominal (see definition #3) diameter. Besides this at 1.82 mm the Hexagon has one of the smallest bores of 3D printer hot ends and hard feeding and/or jams are the most common complaints of their design.

 

Other folks have had issues with Brand name filament.
I have sent back one roll of Taulman because it was OOS.
They will replace it for you, but if replacing the printer is easier for you then go right ahead -- it is your call.

 

I have one spool of Alloy 910 that is as thicker than 1.8 in various spots along the roll. I did not return it because I use and E3D which has a 2 mm bore. But Robo isn't the only manufacturer that uses the Hexagon. Good luck with whatever you decide.

 

This measurement was after baking the filament for 2 hours at 150°F. It is not beyond the scope of reality that even Taulman can have filament out of spec. And PCTPE is more flexible than Alloy910, so it may be more compressible also.

I don't own an R1+PLUS but you can start a new thread in general and ask if anyone has done this specific upgrade and what their results were.