LFS resin tank damage and wear
LFS resin tank damage and wear
The bottom of Formlabs LFS printer resin tanks (for the Form 3, Form 3+, Form 3B, Form 3B+, Form 3L, and Form 3BL) is made of two layers of flexible film separated by an air gap. During printing, the printer pulls on the film layers to create a taut, uniform print area for each layer. Damage to one or both film layers may affect print quality or lead to a resin spill.
Marks on lower film (polishing)
During a print, the two tank film layers rub against one another. Over time, this friction can polish the film and make it appear clearer than the film in an unused tank. This is a normal result of printing and does not damage the tank or affect print quality.


Resin caught between film layers (optical coupling)
Holes in the resin tank film layers may be hard to spot as the air gap between the layers makes the tank bottom appear translucent. Usually, only the top layer of film is punctured. If this happens, resin can leak into the gap between the two layers. Resin trapped between the two film layers forms a transparent blemish in the resin tank. Cured resin or air bubbles may also stick to the inside of the tank near the puncture.

Resin does not spill into the printer unless both film layers fail. To prevent a possible resin spill, dispose of damaged tanks immediately. Do not attempt to print around the damage. If you have any questions about the tank damage, please contact Formlabs Support.
Gouges and punctures through both film layers
Gouges and punctures damage both layers of a resin tank's film. A gouged or punctured tank requires immediate disposal and replacement. Gouges and punctures in the resin tank film not only bend light and prevent the laser from curing resin properly during normal printing, but also present a leak risk. Resin may leak out of the tank, leading to damage to your printer. If you have any questions about the tank damage, please contact Formlabs Support.


Top view of a puncture in a Form 3 resin tank
Bottom view of a puncture in a Form 3 resin tank
Common causes for gouges and punctures include:
- Using a sharp tool inside the tank
- Using excessive force to scrape the tank
- Print failures
VHB tape tearing
Over time, exposure to resin weakens the VHB tape that secures the tank film to the tank frame. This issue is especially prevalent in tanks used with materials that require a lot of mixing (e.g., Durable Resin, Flexible 80A Resin, and Elastic 50A Resin), tanks used with chemically aggressive resins, and tanks that have reached their maximum lifetime. The tape may peel off the tank frame and float inside the resin tank or attach itself to a printed part.
For more information about chemically aggressive resins and tank lifetime, see:
- Resin tank lifetime and monitoring (Form 3/Form 3B)
- Resin tank lifetime and monitoring (Form 3L/Form 3BL)
If you see the VHB tape peeling in printed parts or in the resin tank itself, immediately dispose of and replace the resin tank. If you have any questions about the tank damage, please contact Formlabs Support.

VHB tape peeling off the tank frame and into the resin tank
VHB tape failure
The adhesive that secures the VHB tape to the tank's film can degrade over time, especially from exposure to chemically aggressive resins in tanks that have reached their maximum lifetime. While the majority of the tape may stay intact, any separation can cause resin to leak between the layers of the tank film or spill into the printer.
For more information about chemically aggressive resins and tank lifetime, see:
- Resin tank lifetime and monitoring (Form 3/Form 3B)
- Resin tank lifetime and monitoring (Form 3L/Form 3BL)
If you see the VHB tape separating from the tank film, immediately dispose of and replace the resin tank. If you have any questions about the tank damage, please contact Formlabs Support.

VHB tape separating from the tank frame
Significant VHB tape separation
In rare cases, the adhesive that secures the VHB tape to the tank film fails completely, even after short-term use of a resin tank. This significant separation can cause extensive resin spills inside and outside the printer.
If you see the VHB tape separating from the tank film, immediately dispose of and replace the resin tank. Make sure to clean up any resin spills before continuing to print.
- Cleaning after a resin spill (Form 3/Form 3B)
- Cleaning after a resin spill (Form 3L/Form 3BL)
- Cleaning an extensive resin spill (Form 3) [EN] [DE] [ES] [FR] [IT] [JA] [ZH]
- Cleaning an extensive resin spill for the Form 3L [EN] [DE] [ES] [FR] [IT] [JA] [ZH]
If you have any questions about the tank damage, please contact Formlabs Support.


Tank film peeling off the tank frame
Resin spill due to VHB tape separation