So Tronxy crapped it's bed surface. The surface is a detachable plate with a Buildtak like surface. Not sure what material the plate is, but it is quite rigid, maybe somekind of fiberglass? Anyways, the buildtak-clone surface has been getting worse, with small dents and holes and finally it started cracking and peeling of the plate. It finally gave away when I needed to print some larger pieces witth PETG and heated the bed to 80C; the glue between the plate and the surface just gave up and the surface detached from the plate, causing a warped print as I didn't notice the peeling off.
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So as I needed to get the prints done and Tronxy is the only printer with big enough build area curently, I just cleaned the crappy glue from the plate, sanded it a bit and tried printing directly to it. And it works like a charm with some gluestick, at least with PETG. The parts pop off guite easily after cooling. And the print bottom has nicer finish than with the original Tronxy surface that was always leaving some black stuff on the bottom.

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