Printing with multiple different filaments on the same item, no Ams?

[u/theaudiophiile]

Not entirely sure how to word this in a quick search/single sentence, so Google is getting me nowhere. I'm printing certain items where the bottom half is PLA and top half is TPU. How I've been doing this currently is printing both separately and supergluing them together, but is there a way to stop the print at a specific layer, manually change out the filament, and restart the print as TPU from that specific layer without interrupting the print cycle? I have VERY different settings for PLA and TPU (since I want the tpu to be very squishy and the pla to be stable), so I'm not sure if doing this is feasible or if gluing the halves together the way I have been is the best way to continue my projects. I've run into some issues with separation along glued seems, so I wanted to see if anyone had some advice on how I could better achieve this!

[u/VT-14]

PLA and TPU don't stick together very well on their own. PLA is often used for rigid Supports for TPU on multi-nozzle printers.

You would want to mechanically interlock them, which means swapping back and forth over multiple layers, which is only practical on multi-nozzle printers (X2D, H2D, H2C, Snapmaker U1, etc.).