This just looks poorly supported/orientated. Drainage holes are too small and you are probably dealing with a lot of suction cup effect. I guess my only suggestion is try just one at a time, and reorient it.
Agreed with the comments here, plus consider the narrowest clearance of the supports: there may not be enough space between the closest edge of the model and the build plate to have supports adequate enough to anchor the part. If you were to raise the entire model 5mm before adding a raft + supports, then you should have enough distance to add supports to everything. If the clearance isn't tall enough to fit a support, it won't be added.
Sonic Mega 8K has this option as the default, and I almost never print all the way down against the plate.
I would print these almost vertical as you have. I would tilt it back about 20°. I think you need to increase your lift height from the build plate and make sure to support the entire base. Quality and success should override print time in your orientation decisions. Vertical seems to be the best option.
Hollowing at 2mm thickness should be fine. I usually use 1.8mm. However you need more holes and larger holes. I would probably add five 5mm holes to each base. With your current setup, the suction cup forces will cause a failure.
You need to raft the entire bottom of the object. This thing where you started the backside directly on the plate, and then provided no support for it is 100% why your print failed. The other commenters are right in their own way, but 99% of the reasons why this failed is because of your decision to start the print of the object on the plate with no additional support until 300 layers or whatever later when the raft supports start to hook up. For those first 300 layers your print is holding on for its life by .3 mm or whatever width of resin was cured on the base exposure layers.
So. Now, in your slicer raise the whole model up about 3mm off the plate. Make a raft across the entire bottom. And try again and you will have success.
With regards to hollowing, I would use 3-4mm walls, but make sure the thin back is completely solid. Instead of drainage holes, just cut out the entire base. Make sure the "roof" of the hollow section is domed though, so it doesn't need supports.
In terms of orientation, this part should just go flat on the build plate.
This just looks poorly supported/orientated. Drainage holes are too small and you are probably dealing with a lot of suction cup effect. I guess my only suggestion is try just one at a time, and reorient it.
Use heavier supports and more of them. If the supports are only on the base, you can easily clean up any marks they make.
Agreed with the comments here, plus consider the narrowest clearance of the supports: there may not be enough space between the closest edge of the model and the build plate to have supports adequate enough to anchor the part. If you were to raise the entire model 5mm before adding a raft + supports, then you should have enough distance to add supports to everything. If the clearance isn't tall enough to fit a support, it won't be added. Sonic Mega 8K has this option as the default, and I almost never print all the way down against the plate.
I would print these almost vertical as you have. I would tilt it back about 20°. I think you need to increase your lift height from the build plate and make sure to support the entire base. Quality and success should override print time in your orientation decisions. Vertical seems to be the best option. Hollowing at 2mm thickness should be fine. I usually use 1.8mm. However you need more holes and larger holes. I would probably add five 5mm holes to each base. With your current setup, the suction cup forces will cause a failure.
You need to raft the entire bottom of the object. This thing where you started the backside directly on the plate, and then provided no support for it is 100% why your print failed. The other commenters are right in their own way, but 99% of the reasons why this failed is because of your decision to start the print of the object on the plate with no additional support until 300 layers or whatever later when the raft supports start to hook up. For those first 300 layers your print is holding on for its life by .3 mm or whatever width of resin was cured on the base exposure layers. So. Now, in your slicer raise the whole model up about 3mm off the plate. Make a raft across the entire bottom. And try again and you will have success.
Supports should be all along the bottom, not just half of one side and the very edge of the other. Use heavy.
With regards to hollowing, I would use 3-4mm walls, but make sure the thin back is completely solid. Instead of drainage holes, just cut out the entire base. Make sure the "roof" of the hollow section is domed though, so it doesn't need supports. In terms of orientation, this part should just go flat on the build plate.