How to Fix V Shaped Resin Print Failures in Flexible Resin
- Tamara Arkhangelskaya
- 7 days ago
- 3 min read
In our work with resin 3D printing, we frequently handle various materials. Among them, flexible resin has shown to be the most sensitive to small changes in process conditions. Because of this sensitivity, it has also proven to be the most revealing when testing and diagnosing print failures. One specific issue we encountered is a recurring type of defect that forms a distinct V shape in the final print.
After analyzing several failed attempts and conducting targeted experiments, we identified the main causes and practical solutions for this problem. We are sharing our findings here to help other users who may be facing the same issue but struggling to find reliable guidance.
The failure typically appears as follows. At some point during the print, the part stops forming correctly in one or more areas. From a side view, a V-shaped void becomes visible, where both the model walls and internal supports are missing. Although the printer continues to work until the end of the job, the final part has a section that is entirely absent, forming a noticeable V cut into the geometry.
Inspecting the Film Condition in the Resin Tank
Through repeated testing and documentation, we found that the most frequent root cause is the condition of the film inside the resin vat. This film is known as the PFA Release Liner Film and it sits at the bottom of the resin tank, directly beneath the printed model. Over time, this film degrades from repeated use. The degradation may not be obvious to the eye, especially when working with opaque resins such as black, gray, or white. Wear and tear can take many forms including scratches, fogging, cloudiness, reduced transparency, or slight warping of the film surface. These minor defects are enough to disrupt the print process.
We recommend removing the vat from the printer and inspecting the film carefully under a direct light source. Look for signs of wear or irregularities. Photo above in this post shows an example of a film with visible defects that are likely to cause print issues. If you find damage in the area where the failed print occurred, try repositioning your print to a different location on the film that is still in good condition. Alternatively, if the wear is spread across the film or covers the main area, it is best to replace the film altogether.
Cleaning the Resin Tank and Filtering Resin
Another common cause of V-shaped failures comes from incomplete cleaning of the resin tank. Leftover cured resin particles or small fragments of failed supports can float in the resin and interfere with the print process. These particles may stick to the bottom of the tank, or worse, block the curing of the next layers in isolated areas, creating empty regions in the model.
To avoid this, always pour the resin through a fine filter when transferring it back into its storage container. This helps to catch large debris. After that, take extra care to clean the tank itself. Wipe the corners and edges with a lint-free cloth. Use isopropyl alcohol to remove any remaining residue or sticky spots. Repeat until the tank is completely clean. Our next photo shows a print that failed due to a combination of film wear and contamination in the resin.
Reviewing Print Settings for Flexible Resin
Once the film is confirmed to be in good shape and the tank is fully clean, the next step is to review the print settings. Flexible resins often require specific exposure parameters. Check the exposure time and bottom exposure time settings carefully. Confirm that the rest time after each layer retraction is sufficient for the resin to settle. Additionally, examine the support structure settings. Use a density and thickness that match the model size and orientation. Changing the orientation of the model can reduce strain on overhangs and improve adhesion between layers.
After applying all the above steps, we achieved consistent successful prints. Our main photo displays a part printed under the corrected conditions. No V-shaped gap is visible, and all model features are complete.
If you are facing this type of resin print failure, begin by checking the film condition, then clean the resin tank completely, and only after that revisit your print settings. In our experience, this sequence solves the majority of cases and leads to reliable flexible resin printing. If you want dependable prints without dealing with the technical steps, you can use our SLA 3D printing services and we will handle the printing process for you.
