Layer Geometry Optimization to Reduce Peel Stress and Material

Flat surfaces should not be printed as a uniform layer. I believe you can reduce material use, increase print speed, and decrease the peal force (that tends to warp parts and fail prints) by introducing parallel gaps between laser passes and then alternating the direction of those parallel gaps between layers. In essence, you would use the laser to weave multiple layers together. Please reference the attached image.

. Other laser weave geometries are possible such as hexagon weave, or variable weave angles between multiple layers. I specifically would love this feature on my form 1+ since that would help eliminate the warping on parts that require high precision.

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I don’t know much about such things but what you propose sure seems to make sense !

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This wouldn’t reduce material use as the uncured resin would be trapped inside the model, and since the pattern (at least as you proposed it) isn’t closed it would also slowly leak… if you add a skin to the model like FDM slicers do, then the resin would truly be trapped and would escape slowly as soon as the skin is broken which may be an issue depending on the environment in which the part is being used.

As for peeling parallel to each layer’y orientation that would also require the tank to be able to along the X AND Y axii not only one of the two which is the case currently. The surface in contact with the tank is also 2x the surface area that is in contact with the previous layer, which may lead to other peeling issues.

I’m not saying you’re wrong in theory but I don’t really see this working in practice, certainly not as a software patch for current machines.

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As you can see in the attached animation in this Google Drive Link HERE, there would be plenty of micro channels for the resin to escape from. Even assuming that the laser cures the resin in the gaps above the laser paths (which I think would likely be the case), there would still be channels for resin to escape on the sides. Even if the resin is trapped for some reason, then a post cure would solve that issue while reducing peel force, which is my main issue.

I think you make a good point about the 2x relative increase in surface area surface area interacting with the tank than the previous layer though. As long as the strength between the layers is greater than 2x the peel force with the tank, it should be fine. I don’t have the data on the layer strength verse peel force, so that’s a form labs question. Realistically, the laser will cure the resin in the gaps above and so this probably would not be an issue.

As for the peel direction relative to the laser lines, I’m sure there is an optimal angle where any stress difference between laser path directions would be negligible.

How wide would these micro channels be ? I am having trouble removing resin in <Ø1mm shallow holes even with compressed air, I can’t really imagine having to clean thousands of these within a part.

Fair point :wink:

Fair point as well. There’s probably an optimal channel size, but I think it is possible that a vacuum chamber might work in this scenario. It would probably work even better if there were some dissolved gasses in the resin though.

There are a lot of bridges in that print. I know they’re far shorter than the Form 2’s minimum bridge length, but remember lasers are analog (scattering, etc) and I still have to wonder about how much partially-cured resin is being created at the fringes which might cause other issues.

'Course there’s no way to know for sure unless you try. It’s an interesting concept; let us know how it works out if you do!

As thick as the resin is; the surface tension would be too great to allow the resin to drain.

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And if it did drain, wouldn’t it leave the sides of the print porous? Seems like it would have a negative effect on finish.