Looking for Auto-Leveling Solutions & Mechanisms for MSLA Printers

[Subhash_K]

Hey everyone,
I'm working on a resin MSLA 3D printer project and exploring ways to implement an auto bed leveling system. I’m aiming for precise parallel alignment between the build plate and the resin vat to reduce peel forces and avoid print failures.

I’m looking for ideas, suggestions, or experiences related to auto-leveling mechanisms specifically for resin printers — this could include mechanical systems, sensor types, actuation methods, or even software-based solutions.
If you’ve come across or designed any interesting mechanisms or concepts, I’d really appreciate your input! Diagrams, links, or references are also welcome.
I’m working on a desktop-scale MSLA printer (about 200mm x 120mm build area). At this size, even a slight tilt or uneven pressure can cause one side to cure harder, increase peel forces, or lead to failed prints on large flat layers.


Manual bed leveling (paper test, screw adjustments) works but I’m curious about more advanced methods like:
Actuation mechanisms (small linear actuators or motorized adjustment screws)
Sensors — maybe capacitive, inductive, load cells, or strain gauges to detect uneven pressure
Software-based tilt compensation or probing routines
Using kinematic mounts or compliant mechanisms for self-alignment
Thanks in advance for any help!

 

[IRstuff]

Is that really necessary? I think most people would use a bubble level, once, unless they're trying to 3D print on a rolling ship deck. A good user experience might be had by simply including a couple of digital level sensors in the build plate with some sort of visual bubble level display.

 

[rb1957]

maybe a liquid epoxy that sets over time would create a "perfectly" flat surface ?

how big is this ? 10ft^2 ? a 1" thick plate with leveling screws and lock nuts ?

 

[3DDave]

For typical resin printers, after the first layer is cured on the build plate, it is perfectly aligned to the bed. The only source of misalignment will be in the lift mechanism.

Is there a diagram that shows the problem you believe you will have?

 

[Subhash_K]

Is that really necessary? I think most people would use a bubble level, once, unless they're trying to 3D print on a rolling ship deck. A good user experience might be had by simply including a couple of digital level sensors in the build plate with some sort of visual bubble level display.

Thanks for the suggestion, IRstuff! You’re right — general printer leveling is typically a one-time job with bubble levels or digital sensors. What I’m looking into is a bit more micro — focusing on automating the parallel alignment of the build plate to the resin vat’s FEP film surface. Even slight tilts can increase peel forces in resin printing, especially on large prints.
Manual bed leveling (paper test, screw adjustments) works but I’m curious about more advanced methods like:
Actuation mechanisms (small linear actuators or motorized adjustment screws)
Sensors — maybe capacitive, inductive, load cells, or strain gauges to detect uneven pressure
Software-based tilt compensation or probing routines
Using kinematic mounts or compliant mechanisms for self-alignment

 

[Subhash_K]

maybe a liquid epoxy that sets over time would create a "perfectly" flat surface ?

how big is this ? 10ft^2 ? a 1" thick plate with leveling screws and lock nuts ?

Thanks, rb1957! Good point on creating a flat reference surface — and yes, I should’ve clarified the size. My build area is about 200mm x 120mm — desktop scale, not industrial. Pouring an epoxy layer sounds ideal for large machines but may be overkill here. What I’m really chasing is a dynamic or semi-automatic system to maintain parallelism — possibly with micro-adjusters or sensors — to prevent uneven curing forces during printing. Still, that epoxy concept might be useful for a perfectly flat reference base. Appreciate the idea!

 

[Subhash_K]

For typical resin printers, after the first layer is cured on the build plate, it is perfectly aligned to the bed. The only source of misalignment will be in the lift mechanism.

Is there a diagram that shows the problem you believe you will have?

Thanks, 3DDave — you make a great point. After the first layer, the print is locked to the build plate — totally agree. The issue I’m concerned about is the initial alignment. Manual leveling can work but for larger prints, slight tilts cause uneven exposure and increase peel stress, sometimes leading to failures or warping. I’m exploring if load cells, capacitive sensors, or even small linear actuators could sense/correct this tilt before printing starts. Do you think the lift mechanism itself could incorporate some self-leveling features?
Would you be interested in seeing the sketches? Also curious if you’ve seen any lift mechanisms that integrate self-leveling or compensation like this.(Automatic Leveling and locking needed)

 

[rb1957]

"What I’m really chasing is a dynamic or semi-automatic system to maintain parallelism — possibly with micro-adjusters or sensors — to prevent uneven curing forces during printing." ... so what you want is a rigid platform ? To visualise a system where you allow a deformation, then sense this, then correct this sounds "byzantine" ... prevent the deformation in the first place with a rigid base.
But maybe you mean "what if faces that are supposed to be parallel distort in the curing process ?" I guess the olde answer would be "include a machining allowance and machine parallel after manufacture". Else separate these faces that need to be tightly controlled and make the thing an assembly (assemble the components with the required parallelism).

 

[IRstuff]

Alignment with what?

The print head? That's normally done as part of the calibration process; you should be able to zero the print head to each corner of the build plate.