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I have been working with our SLA printer (Facture Draken) for a couple weeks now printing in makerjuice waxcast. . I have had some successful prints, but the majority (80%) end up as pancakes stuck to the bottom of the resin tray. Some others break in half mid print.

I have experimented with laying my models (round circular diks) flat on the build plate, but most of the times I place them on supports which stem from a square baseplate.

It seems clear to me that there is allot of force being put on the models while curing on the bottom of the resin tray. I have noticed that printing objects with a larger projection area are more likely to stick in the vat. I assume this is because of the increased contact with the tray. Usually it seems ~10 layers are built before my baseplate breaks away.

Things I have tried

  • Pulling out the build plate, cleaning it with Acetone. Sanding it with 80 grit sandpaper.
  • Emptying the resin tray and replacing with new resin.
  • Upping base-layer cure-time from from 30seconds up to 3 minutes, and variations between.

  • Upping base-layer count from 2 to 4.

  • Rotating model base 45% to start the tray peel process from a corner rather than from a long edge to reduce initial tear force.

Anyone with experience got more suggestions on how to continue troubleshooting?

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  • $\begingroup$ Ive bought a new resin tray, should be arriving sometime soon. Ill keep you all updated on progress. $\endgroup$ – DMrFrost Jul 13 '17 at 8:18
  • $\begingroup$ I'm new to SLA printing and am not entirely sure about the accuracy of these infos (thus not an answer), but there's one thing I haven't seen mentioned in the answers: my printer has a vat with a FEP film. This can become too sticky (via scratches and dents) and then needs to be replaced. I've read that using a small amount of teflon lubricant can help in this case as well so the cured resin doesn't stick to the FEP film any more. $\endgroup$ – DarkDust Nov 18 '19 at 10:00
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Prints could end up on tray for couple of reasons.

  • Vacuum force on early layers - Usually you should lose pieces on the center of platform
    • Put holes or channels on platform
    • Very slow speed on early layers
    • Use smaller platform
    • Use tilt mechanism
    • Use larger support structures
    • Use stickier platform - Anodized aluminum is specially good
  • Non-aligned platform - Pieces on side of platform end up on tray
    • Align platform / tray
  • Low cure times - you could lose pieces around platform for DLP and whole platform for LCD ones
  • Resin related issues
    • Resin designed for thinner layers - Decrease layer thickness
    • Pigment settled down - Shake resin before use
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I also had issues with the first layer sticking to the build plate and I did not want to sand the plate. As most people will mention you need to make sure that your plate is perfectly level and the z height is right (lots of friction on the paper). You also need the correct exposure times for your resin and the first few layers should get 60 seconds of exposure. PRO TIP to improve bed adhesion: apply a thin layer of resin to the build platform before you start to print. I have not any failed prints after I started coating the plate with resin. Also, I don't completely clean the plate between prints, I make sure it is still sticky. I hope this helps.

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I had the same exact problems. Nothing would stick to the platform. One day I realized, that all of the failed prints would always start to fall off to one side, and all of the successful prints were all misformed and kinda diagonal. The platform was not level.

Another problem that I more recently had was that I left resin on the plate for a couple of months and it hardened which doesn't allow printing at all.

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  • $\begingroup$ Did you fix the latter issue? I would suggest to physically scrape/sand the resin layer off. $\endgroup$ – Trish Apr 15 at 13:22
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I have a plain smooth aluminium build plate and it seemed that all problems with adhesion which I had were caused by the plate not cleaned well enough with IPA and a paper towel, after removing (allegedly) the rests of the previous model with a metal scraper. The new model was peeling off only in places where the old model was previously attached. Now I clean the plate thoroughly, tightly pressing the towel, and there are no more peel-off problems with any resin. I have even reduced the typical exposure times of bottom layers because otherwise the model might be attached too strongly.

See that this tip is opposite to what is suggested by Michael. I guess that Michael had problems with trapped air which escapes more easily if the plate is wet. I have a risky but working method for trapped air.

Also, check the plate angles if you didn't do so. The angles should be well adjusted by allowing the plate to rest slightly pressed to the calibration pad with the plate's screw loose before tightening it again and adjusting the height.

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