Ok here is the thing, supports take 1/3 to 1/2 of resin print, throw away… I put my model like in reality with supports walls are vertical it takes less resin than if you use auto rotation and supports, like you can see on pictures first and second picture.
As you can see first rotation is best for material consumption and time printing, second is worst and third is optimum. I would print walls vertical but everybody are saying that is not good for model warping. what to do ? third option ?
This is a good lesson in not relying completely on the automatic orientation and support generation.
Quite often it makes more sense to manually rotate the part into position and then add supports. I normally use the automatic supports and then modify them manually to keep them off of sharp corners.
Sometimes it makes sense to cut a model like that into pieces and create connection features. More of a hassle but if its not at the detriment to your project it can save a ton of print time and a good amount of resin.
In our experience, sloping walls will always be more accurate than flat walls. I presume that printing a single large flat area is far more prone to warping due to suction for that first layer. You basically have a very very thin layer with very little support and when the printer pulls up on it you can get deformities. With angular contact you have a smaller surface with far more support. That being said, there is definitely a diminishing returns effect with regard to the angle used. Unfortunately I don’t know where that sweet spot is.
There are definitely undocumented lessons to learn from this printer. We do print models flat, similar to your first picture, but we manually create ~3mm “nubs” and print directly against the plate. Printing directly against the plate without the nubs is a no-no as the part can easily fracture when trying to remove it. The downside of our “nub” technique is that cosmetically the flats around the “nubs” would be unacceptable to most, i.e., they are almost never truly flat. The parts we do this with are for testing purposes only, so cosmetics are not a concern.
This is just an example, view from below. We have no set standard on nub diameter or length. Like I mentioned the bottom of the part comes out poorly, but the rest of the part is flawless. Actual parts are way more complex than just a tube up top, we also directly print threads that work pretty darn well.
It is printing at the moment with custom supports 0.11 ml I forget to prtscn. 129 layers with 1 hour and 17 minutes
Less resin, dont know why it had take 10 minutes more but on bigger scale I think you would use much less resin than generating automatic supports
That part is an issue due to how thin some of the edges are–you need to avoid printing a part parallel to the build surface, the bottom edge will never ever be flat and straight and will often have layer damage where you can see some of the early layers are coming apart.
What would probably be the best orientation would be with the ends facing downwards so that the starting points are on those ends and easy to clean, with the two thin parts facing upwards so you don’t have supports on those edges and they should print pretty cleanly, then you would have supports on the flat surface and it’d be easier to sand those surfaces after. Still tilt it a bit in both directions so that it’s starting on corners. It might still warp but it’s the best chance to get a good result.
I use the auto orientation and support generation as a starting point. If I don’t like what I see, then I clear the supports and tweak the orientation before regenerating the supports.
Some of my first prints were failures since I tried printing long flat surfaces parallel to the build platform. The peel placed more stress on the parts than it could handle. It seems that the sweet spot is somewhere between 30 and 45 degrees relative to the build platform.
I also try and orient the model to have the least amount of surface area to print and peel per layer. Another thing I try to avoid is narrow rafts on the build platform, If I have a bunch of parts I’ll lay them out so the rafts intersect so it results in a wider contact patch.
Let us know what else you come up with during experimentation. Unfortunately I don’t have much time to be playing around with our printer and our current methodology works well enough.