Random fails, how to improve success rate

I’ve printed a 1000+ of these in different iterations, almost all directly on the build plate and for most of the times it works fine but I do have random fails where parts do not stick to the build plate, flakes comes off and ruins the rest of the batch and forces me into a nasty cleanup.

Initially I printed without any supports, then added these small tabs on the edges and that worked great for a while, now though I’ve had two of the last three batches fail due to one not sticking. And it has happened in the middle and rear parts of the build plate.

Printed like this each model consumes 5.2ml, fully supported it’s 7.2ml, that’s a 38% increase which for sure makes an impact given the resin prices (using Tough 1500).

Some measurements of these parts are critical and I’ve learnt over time that how they are printed and cured have a significant impact. Printed like this I’m getting a consistent +/- 0.05mm accuracy.

The more supports I add the more post processing I need todo and give the accuracy needs some areas can’t be supported and I can’t print without the “negative elephants foot” block as that would have resin float out and completely ruin some critical edges.

I’m reaching out now to hear other peoples experiences and see if there is a smart way to improve my success rate without increasing resin use or post processing too much.

Printing them on the side will not work, for some reson they alway warp when cured if printed like that, not sure why but that’s what happens.

This is what the result from above print looked like. I was lucky to catch in the early stages so it didn’t fill up the entire tank with flakes.

It still needs cleaning though.

I have this issue with my castables (purple)
sadly my solution is adding the supports.

The objects we print are small as 10mm and thin as 0.07mm, with the full rafts supports touching just a little.
If we do not support, it either gets swept away from the mixer, pushed out by the wave of resin, or stick to the bottom of the tray.

Too much resin in the tray can also cause detachment.

As long the build plate is clean, wiped with iso, and dry, I don’t have problems.

Good luck on finding your solution.

Hello @Reine ,

I agree with Drew above on this - supports are there to maintain rigidity of a part, and I do understand cost is a concern, but failures are also costly.

That said, the overhang looks to be too much to print this on its side. The mass of the resin and large surface areas per layer would be a different sort of issue which would cause the resin to warp in the print process from force on the part.

Regards,
-Jen