So I printed molds of ABS for vacuum forming.
The molds warped in the first vacuum forming process. the mold had 30% infill. I guess the mold could not withstand the vacuum forming machine temperature. So I applied vinyl ester on the second mold to with stand the temperature.
On vacuum forming this part, the mold stuck to the sheet and is not coming out. And I am guessing after using the same mold for more than once it will warp.
IT would be great if someone could give me insights on what could be done in the mold model or post processing the mold model for a successful vacuum formed part. I am aiming for 1000 vacuum forms out of the 3d printed molds. Is it possible? all kinds of insights are welcom and required! 
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Out of curiosity, what wall thickness are you using for the molds; upping the wall thickness could have a much bigger impact on strength than infill in my experience.
Enza3D
3
ABS has too low of a melting and glass transition temperature for vacuum forming, unfortunately. It works well to vacuum form with, but not so much as a mold substrate. You can try coating your master in very fine thin layers of plaster (like what is done with foam masters) and see if that helps to form a heat resistant shell. Just work in very small batches, and sand between coats to get a nice surface finish. Coat the masters with a nice thick layer of petroleum jelly right before forming, and it might work.
I assume you have an FDM printer, but another option is to use Formlabs High Temp resin, which is designed specifically for injection molding and thermoforming.
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The wall thickness that we used was 0.8mm, I think we ll double it and try?
Thanks a lot! I shall definitely try coats of petroleum jelly and plaster in two separate moulds.
Yes we printed our mold in Ultimaker, FDM printer.
What temp are you vacuum forming at? PC has a Tg of 147 vs 105 for ABS, might be enough to make it through. It’s a pain to print with though.
High temperature PLA!
Try this stuff: Iridescent Ice HTPLA | Translucent PLA Filament – ProtoPlant, makers of Proto-pasta
You anneal it in the oven for 45 minutes, and then it has high temperature heat resistance and great deflection.
Really easy to print with, normal settings. It is really great stuff.
