Resin supports need to be removed, cleaned up, and disposed of properly after every print. The process is straightforward once you know the right timing, tools, and techniques. Here’s how to handle every step, from snipping supports off the model to dealing with the leftover waste.
Remove Supports Before Curing
The single biggest decision is when to remove supports: before or after post-curing. Removing them before curing is almost always the better choice. Uncured resin is softer and more flexible, so supports snap off cleanly with less force and less risk of tearing chunks out of your model. Once a print has been fully cured under UV light, the supports become rigid and brittle. Cutting them at that stage is more likely to leave deep pockmarks or crack delicate features.
After washing your print in isopropyl alcohol (IPA) to remove excess uncured resin, work through the supports while the part is still in its “green” state. You can then sand or touch up any remaining marks after the final UV cure, when the surface is hard enough to take sandpaper well.
Tools That Make Removal Easier
Flush cutters are the most universally recommended tool. They cut cleanly right at the contact point without crushing the surrounding surface, and they’re far safer than box cutters or craft knives. A good pair of flush cutters and a set of micro needle-nose pliers will handle 90% of support removal. The pliers let you grip and twist stubborn supports, while the flush cutters trim whatever’s left at the base.
For finer cleanup, keep these on hand:
- Hobby knife (X-Acto): Shaves down nubs in tight corners and detailed areas.
- Deburring tool: Glides along straight or gently curved edges to remove raised material quickly.
- Mini woodworking chisels: Useful for flat surfaces where you want to pare a nub flush without gouging.
Tweezers look like they should help, but in practice they don’t grip support tips well enough to be useful for removal. Save them for positioning small parts during assembly.
Reduce Support Marks in Your Slicer
The best way to deal with support marks is to minimize them before you ever hit “print.” Most resin slicers let you adjust the contact point between a support tip and your model. Two settings matter most.
First, contact diameter. This controls how wide the connection is between the support and the print surface. A smaller diameter leaves a smaller mark and is easier to snip, but it also holds the model less securely. If your print isn’t heavy or cantilevered, reducing the contact diameter even slightly makes cleanup noticeably faster.
Second, contact shape. A sphere-shaped tip creates a ball at the junction between support and model. This design lets you cut the sphere away from the support column without pulling material out of the model surface. It’s especially helpful with rigid or brittle resins that tend to chip when supports are removed. If your slicer offers a sphere contact option, it’s worth enabling for any print where surface quality matters.
Sanding Away Support Marks
Even with careful removal, most prints have small nubs or rough patches where supports were attached. Sanding is the most reliable way to get a smooth finish. Start with a lower grit (around 400 to 600) to knock down raised material, then work your way up through progressively finer grits. By 3,000 grit, the surface will feel smooth and glossy. If you keep going to around 12,000 grit, the surface becomes reflective.
Wet sanding helps on stubborn spots. Running water over the surface or using wet sandpaper reduces friction and prevents the fine resin dust from clogging the paper. It also produces a more even finish since the water carries away particles instead of letting them scratch the surface.
Filling Pits and Pockmarks
Sometimes a support tears away a small piece of the model, leaving a pit instead of a bump. Sanding can’t fix a hole. The simplest repair is to fill it with a drop of liquid UV resin. Use a toothpick or fine needle to place a tiny amount of resin directly into the pit, making sure the resin fills the void without overflowing onto the surrounding surface. Then cure the spot with a pen-style UV light. These handheld lights let you target just the filled area without affecting the rest of the model. Once cured, a quick pass with fine sandpaper blends the repair into the surrounding surface.
For larger holes, you can superglue small pieces of cured support material into the gap as filler, then seal over them with liquid resin and cure. After sanding and painting, this kind of patch is essentially invisible.
Creative Uses for Cured Support Waste
If you’re into tabletop wargaming, miniature painting, or diorama building, don’t throw your cured supports away just yet. Those spiky, organic-looking shapes are surprisingly useful as crafting material.
- Basing and terrain: Thin vertical supports look like tall grass, weeds, or wooden stakes. Thicker pieces work as rubble, broken walls, or rocky outcroppings. Glue them to miniature bases and paint over them.
- Filler for hollowed prints: If you print large hollow models, cured support scraps can fill interior voids to add weight or structural rigidity.
- Diorama debris: Need broken junk, shattered wood, or battlefield wreckage? Cured support fragments look the part with minimal effort.
- Bonding agent: Dissolving cured resin scraps in acetone creates a thick paste similar to “sprue goo” from plastic model kits. This paste works as a bonding agent for joining multi-part resin prints.
- Texture grit: Chop supports into tiny fragments and mix them into texture paste for added surface detail on terrain pieces.
Disposing of Supports Safely
Uncured resin is a chemical irritant and should never go down the drain or into regular household trash. This applies to liquid resin, partially cured supports, and any IPA that has dissolved resin in it. The rule is simple: if it’s not fully cured, it’s hazardous waste.
Supports that were fully cured during post-processing can go in regular household trash. They’re inert solid plastic at that point. But if you removed supports before curing (as recommended), those pieces still have uncured resin on them. Place them in a clear container and leave them in direct sunlight for one to ten days, or expose them to a 405 nm UV light source. Once every surface is fully hardened, they’re safe for household disposal.
Paper towels, gloves, and other supplies that touched liquid resin follow the same process. Lay them out in sunlight or under a UV lamp until any wet resin on them has solidified, then toss them in the trash. Never pour used IPA or other solvents containing dissolved resin down the drain. Disposal rules for contaminated solvents vary by location, so check your local regulations or add them to a chemical waste stream if you have access to one.
Wear nitrile gloves any time you’re handling uncured supports or cleaning up resin residue. Latex gloves don’t block resin effectively, and skin contact with uncured resin can cause sensitization over time.