3d prints curving

[VTRailway]

So im really new to this 3d printing black art. I just picked up an Elegoo Saturn S 4k printer. Ive leveled the bed per the instructions. Ive printrd some calibration prints called the cones of calibration. After a couple attempts, i was able to have success. At least i think so anyway. Im using elegoo standard grey resin. Room temp is 70 deg f. Ive found some girder bridges in thingaverse. They print perfectly except the edge nearest the build plate distort and have a curl. Some are better and almost perfect. Others not so much. Ive tried a higher lift thinking they may be sticking to the fep. Also tilting a few degrees on the horizontal plane. Tried supports, thick supports. A raft with supports. Anyone have suggestions?

 

[bigfoot13]

Possibly add more supports at the end and make sure that their base extends beyond the edge of the object. Also you might increase the exposure time of the initial layers to get better build plat adhession. I'm still new to the resin printing too.

 

[D&J RailRoad]

Only way to figure out the fix is to use more material and time.

 

[747flier]

It's a problem which may be helped by part design and orientation. For my old timey narrow gauge cars the little bit of swayback is perhaps OK.

A couple of things to experiment with, longer supports and a slower lift speed may allow for reduced suction and more even new resin distribution. Parts design may have to be resorted to. Though an object may print as one piece, it may be better to change the orientation and print as several pieces to be assembled. For instance I made a gondola which though would print as one piece came out better as separate ends, sides and floors. Flatcars printed much better almost vertically.

Good luck!

 

[VTRailway]

Thanks for the thougjts and feedback. Beimg im a noobie and looking to learn and understand this voodoo better. What is the benefit of longer supports? These bridges were printed 3mm off the plate with a massive amount of suports automaticly generated. Id adjusted the support density to 100%.
I found this design on thingaverse. Im not sure i can rework using tinkercad. Id be happy to share it along with my support setting and print settings.