Stereolithography (SLA) is a process of curing photosensitive resin from the bottom up, which existing gravity, forces, and movements during printing may affect your resin 3D print to warp. Improper print settings and damaged printer's moving parts are very likely to increase the chance of warping.
Similar to Fused deposition modeling (FDM) printing, resin printing may also experience 3D print warping. However, these issues can be resolved in several effective ways, for example, using a build plate with strong adhesion, enhancing the print base, and correctly orienting the model. This article will discuss how to prevent resin prints from warping on the build plate. I hope this will be helpful to you.
Why do Your Resin Prints Always Warp?
- The build plate is unlevel and loose.
- The build plate has signs of wear and deformation.
- The model orientation is wrong.
- The bottom exposure and bottom layer are inadequate.
Resin print warping at the bottom is typically caused by the printer's hardware and software print settings. The following four methods will guide you on how to solve this issue.
How to Fix Resin Prints Warping?
Method 1: Level and tighten your resin 3D printer.
If your printer's bed is not level, the printed object may have poor adhesion on one side of the bed while sticking well on the other side. Moreover, as the object continues to be produced, its weight increases, leading to warping at the bottom edges. Therefore, make sure your printer platform is tight and level. To handle it, you need to manually re-level the bed by aligning it and tightening the screws. If you have an auto-leveling printer like Anycubic Photon Mono M5s, you can easily perform this task by pressing a button on the printer's display.
Method 2: Check and replace your build plate.
Some signs on the build plate may indicate the need for replacement, such as a deformed build plate or deep scratches on its surface. These signs can result in decreased bed adhesion, then resin prints' base edges may detach during printing. Check your printer plate first for flatness, use the caliper's straight edge as a reference and examine it under light. If it is not flat, you may need to replace it.
On the other hand, many deep scratch marks on the build plate's surface, which can prevent the bottom of the print from sticking well to the plate. Some printer manufacturers, like Anycubic, equip some of their machines such as Anycubic Photon Mono M5s with a checkerboard texture plate to reduce resin print warping. If platforms have too many scratches should be sanded flat or replaced.
Method 3: Optimize the orientation of the model.
Printing in the wrong orientation can lead to print failures, such as always setting vertical or 90° orientations without considering the model's geometry. You should tilt the model at a correct angle to reduce the surface area for each layer, which also decreases the contact area between the plate and the resin vat. In this case, when the plate lifts, the fresh layer experiences less detachment force, making it easier to peel off from the FEP film and reducing resin print warping issues. However, do not forget that printing a model at an angle requires sufficient support to prevent other issues like support and print separation.
Method 4: Increase bottom exposure time and bottom layer count.
Resin prints generally tend to warp at the bottom when their bottom layers are weak and cannot withstand the increasing weight as the resin is continuously curing during printing. It may be necessary to fine-tune the print settings, specifically the "bottom exposure" and "bottom layer" values which are basic parameters for resin 3D printing. For larger-sized models, it is recommended to add more 20 seconds to the bottom exposure time and 5 layers to the bottom, based on the current setting. For smaller models, increase more 10 seconds to the bottom exposure time and 3 layers to the bottom.