To the OP, you are probably best off leaving TPU for PETG and PLA projects and moving to softer PEBAs for high temp filaments like ASA, Nylons, and ABS. I don’t know the polymer compatibility (unsure if they stick together or need to be locked together), but the hot-end temperature resistance is the biggest fear in using high temp materials with low temp materials (TPU clogging in the nozzle). Granted, the point someone made with bed temps is valid too.
I would guess its the “other things” in your statement. Not sure PLA would mix with TPU well enough, but that could be why it sucks in layer adhesion. I would think the layer adhesion might even be worse than it is with PLA. But I noticed 5000 mg’s of PLA-something on Sirya Tech’s 64D MSDS, so I guess anything is possible.
Meant to ask you this, but what is this? I’m guessing this is something that replaced your auxiliary fan on your H2D? I think that’s the top of what I saw in your flexy christmas ornament stream.
Did my first ABS prints on my H2C and my AQ meter showed a spike in small particles and VOC’s at the start of the print. My X1C shows no similar spikes when running my bento box, so I was thinking of how I could add better scrubbing to the printer. Your stream made me think that might be a solution. Thank you for sharing.
I’ve combined 64D TPU and CF-PETG before, and it went alright. Dont mix materials in layer 1 if at all possible, so that you can just set the bed at one heatpoint and forget about that complexity.
Your goal of ASA/ABS might be trouble due to ambient heat. ASA/ABS love/require the heat, but your TPU might want to get softer and clog or wrap around your drive gears and make you very sad. Run as cool as your asa permits and double check the product for Z strength.
A more pure TPU like a 64D instead of the ams stuff might help your goal. Just lie to the printer and tell it it’s TPU for AMS, and set your volumetric flow down way low. The AMS stuff is colorful but it treats heat differently than TPU. IMO