I’ve been using the H2C’s right nozzles with a dedicated material each. It works great for everything, except TPU. The assigned TPU hotend will constantly clog and stall when loading the roll. I can print with the bypass and external spool just fine, it’s an issue limited only to loading and purging old material (so TPU on TPU).
As much as I know that flexibles are not easy to purge, I didn’t imagine that it would prove this annoying. I would probably put the blame on the section left in after cutting, which is way above the melt zone and not easy to push down. I never had issues with my other non-Bambu printers.
Cold pulls works great, mostly because PLA has the rigidity to push everything out.
Anyone with a similar experience?
Would really love to try a cold pull automatic gcode that loads and unloads from AMS. Probably not feasible, there will be plenty of guards against low temp filament moves and no-cut AMS retractions. and you’ll be left with a pretty long thinned PLA string on a spool, and no way of inspecting the results.
I experienced the same problem. Whenever I try to print with TPU for AMS filament, the filament from the previous print doesn’t eject and the nozzle clogs. I’m even experiencing clogging with filaments like PLA or ABS, which I’m currently using for color prints. Recently, I tried to print with PLA, but the filament wouldn’t go into the AMS’s filament feed slot. Upon inspecting the filament, I noticed the end of the rewound filament was swollen (see picture).
I have tpu clogs on the right nozzle often. I have noticed it happens if I stop a print, while printing tpu, nearly every time. If the print stops naturally, its usually fine. It clogs all the way to the cold section. I actually have 3 .4mm nozzles that need unclogged right now.
I use a nozzle unclogging tool(Allen wrench works too) and shove it down the nozzle throat while heatingvthe tip with a torch.
The crappy one is when it happens after its been cut. New filament has nothing to grab and can’t push the old tpu out because(in my case) its stuck above the melt zone
Just to be clear, I can’t get the needle to work either. I have to push it out from behind. With the nozzle not installed on the machine.
