Bent Raft - troubleshooting

Hi Guys
A college of mine recently had a part failure. Model and picture attached. The raft was found bent which (I suppose) led to the part failing down. He restarted the print with the same settings and this time it turned out well. Any straightforward suggestions? It was the black V2 resin.

Am I correct in understanding the raft separated from the build platform during the print?

A few suggestions:

  1. Try lowering the Z Fine Tuning. That will press the platform harder against the tray at the beginning of the print and should help with adhesion.

  2. Inspect the surface of your build platform. If it’s pretty worn, you can sand it. A bit of grittiness can actual help improve adhesion (as long as it’s not deep gouges) and sanding will also level off any protrusions (e.g. nicked up slivers of aluminum) that can damage your PDMS / tank film. Obviously be sure to clean off any dust from the platform before using it.

  3. Inspect your optics (optical windows of your tank and printer, main mirror, etc). If they’re dusty it could be impairing laser power and causing the raft to not fully cure to the build plate. That would probably also manifest as defects on the rest of your print (so if the rest of the print aside from the raft looks OK, this is less likely a culprit).

  4. You could try reorienting your print. If you printed at an angle, there would be less surface area so the peel forces trying to rip the raft off wouldn’t be as great.

If it still gives you problems, reach out to support.

The build plate was dirty/contaminated. The contamination was removed as the failed print peeled away. The retry succeeded because this time the build plate was “clean”.

Thank you both for the answers! I expect the cleanliness of the building platform to be the culprit. However, I will save that thread and start with the suggestions of @rkagerer for future troubleshooting!
Have a nice weekend!