Gomagom 31 Epoxy Putty 30g | Fast Repair for 3D Printed Parts

GomaGom 31 Epoxy Putty is the go-to quick-repair solution for 3D printed parts: a two-part adhesive and filler in a 30 g stick format that bonds and fills simultaneously, setting in around 10 minutes so you can get straight back to work. Cut a slice, knead until the color is uniform, and apply wherever needed — a crack in a resin or PLA part, a gapped joint that super glue alone won't hold, a break with missing material, or a print defect that needs filling before sanding and painting. If you're looking for detailed sculpting with a long working time (miniature conversions, fine sculpting), the right choice is GomaGom 29 Epoxy Putty with a 24-hour cure time.

The go-to product for quick 3D print repairs

The main selling point of this putty is speed. When a large part comes off the build plate with a separated layer, an internal crack, or a porous area, you want to fix it in 15 minutes and keep working — not wait 24 hours for it to cure. That's exactly what GomaGom 31 is formulated for: initial set in around 10 minutes, sanding and handling possible after 1–2 hours, full strength by the next day.

It works as an adhesive and a gap filler at the same time. This matters: super glue bonds surfaces in contact, but it doesn't fill volume. If the part is broken with missing material, or if the crack has any thickness, super glue won't cut it on its own. Epoxy putty will — it closes the joint and adds material to fill the gap, leaving a continuous surface ready for sanding.

Use cases in 3D printing

Where having a stick in the drawer really pays off:

Filling cracks and print defects. Large part with a failed layer, an internal crack that shows up during cleanup, or a porous area from poor layer adhesion. Apply, wait 10 minutes, sand flush, and it's ready to prime.

Bonding broken parts with missing material. If a part breaks and loses a fragment, epoxy putty closes the joint and fills the lost volume in a single step — no need to super glue first and then fill separately.

Reinforcing structural joints in multi-part assemblies. Large prints that were split into sections (handles, shafts, joints) and will be handled or put under load. A bead of putty on the inside of the joint adds mechanical strength that super glue alone can't provide.

Rebuilding rounded edges from under-exposure. A common SLA defect when exposure is insufficient: fine corners and edges lose definition. Epoxy putty lets you rebuild the lost geometry before sanding and painting.

Works on PLA, PETG, ABS, and cured UV resin — the four most common materials in any 3D printing workshop.

How to use it

The process is straightforward — follow it carefully to ensure proper polymerization:

1. Cut equal portions. The stick contains resin and hardener arranged so that cutting a cross-section slice automatically gives you the correct ratio. No measuring, no mixing two syringes — the stick format handles the math for you.

2. Knead until the color is completely uniform with no streaks. This is the critical step. Knead with your fingers (or wear gloves if you have sensitive skin) until the streaks from both components disappear entirely and the putty is one solid, even color. Any remaining streaks mean those areas won't cure properly.

3. Apply quickly to the repair area. Once kneaded, the putty starts losing workability within minutes. For simple repairs (filling a crack, closing a joint, occupying a gap) you'll have plenty of time. For larger repairs, knead in small batches and work in sections rather than mixing all 30 g at once.

4. Initial set in around 10 minutes. From that point the putty is rigid. Sanding and handling are possible after 1–2 hours. For full strength, wait until the next day.

Gomagom 31 vs. Gomagom 29: Which One Do You Need?

We carry two epoxy putties from the Gomagom range, each designed for a different purpose:

• Gomagom 31 (this one, 30 g, sets in 10 min): fast repairs. Fix the part and get straight back to work. Typical uses: closing a crack, bonding a break, filling a defect, reinforcing a joint.
• Gomagom 29 (28 g, 24 h cure): modelling and sculpting. You need a long working time to sculpt fine details, convert miniatures, or model layers, armour and equipment. It's the Spanish alternative to green stuff and Milliput.

If your main use is quick workshop repairs, the 31 is your product. If your main use is fine modelling and sculpting, go with the 29.

Compatibility with 3D Printing Materials

• PLA (FDM) — bonds and fills perfectly
• PETG (FDM) — good adhesion; sanding the contact area is recommended
• ABS (FDM) — good adhesion
• Cured UV resin — works well on properly washed and cured prints

For joints that just need gluing without filling volume, cyanoacrylate is faster and cleaner — we carry the Gomagom 9 Super Adhesive with brush applicator, which is the go-to option for that.

General Repair Uses

Beyond the 3D printing workshop, the official Gomagom catalogue lists the following applications: swimming pools, metal, pool tiles, marble, terrazzo and pipes. In practice, it's a great fit for any household repair where you need to bond and fill at the same time: fixing a saucepan handle, sealing a small leak, setting a raised tile, rebuilding a chipped ceramic corner. Once cured, the putty can be sanded, drilled and painted.

Technical Specifications

• Type: two-part epoxy putty in stick format
• Content: 30 g (resin + hardener co-extruded)
• Mixing: cut equal parts and knead until a uniform, streak-free colour is achieved
• Working time: a few minutes after kneading (ideal for repairs)
• Initial set: approximately 10 minutes
• Sanding and handling: 1–2 hours after application
• Full cure: 24 hours for maximum strength
• Finish: sandable, drillable and paintable
• Colour: transparent / light once mixed
• 3D printing compatibility: PLA, PETG, ABS, cured UV resin
• Manufacturer-recommended applications: swimming pools, metal, pool tiles, marble, terrazzo, pipes
• Manufacturer: DUNSA (Gomagom brand, Spain)
• Reference: SKU 15026

Why Buy It from Mr Resin

Keeping a stick in your drawer saves you a trip to the hardware store the day a large print comes out cracked or you need to fill a gap that cyanoacrylate won't cover. If you're already placing an order for resin, filament or paint, adding the 31 goes in the same shipment at no extra cost. Free shipping to mainland Spain on orders over 79 €.

Mr Resin has been serving over 5,000 makers across Spain, Portugal and France for years. Our catalogue is built around what the community asks for: printers and materials at the core, plus the workshop consumables that become part of everyday use.

Frequently Asked Questions

Can it fill cracks and defects in 3D printed parts?
Yes, that's exactly what it's for. Cut a slice, knead until the colour is uniform, and apply it over the crack or gap in the printed part. It sets in 10 minutes, you sand it flush after 1–2 hours, and it's ready to prime and paint. Works on PLA, PETG, ABS and cured UV resin.

Can I use it to repair a broken resin-printed part?
Yes, this is one of its best use cases. The putty bonds and fills at the same time, making it perfect for repairs where the part hasn't just broken but a chunk has chipped off or the joint doesn't close cleanly. For UV resin-printed parts, we recommend making sure they've been properly washed and cured before bonding, and lightly sanding the contact area to improve adhesion.

Is this putty suitable for miniature conversions, or do I need a different one?
For simple miniature repairs (a broken arm, a lost detail, a gap to fill) the 31 works great. For detailed conversions that involve sculpting layers, shaping armor, or adding equipment where you need a comfortable working time, you'll be better off with the Gomagom 29, which has a 24-hour cure time and is the Spanish alternative to Green Stuff and Milliput. The 31 sets too quickly (10 min) to sculpt at a relaxed pace.

How long do I have to work with it once mixed?
Just a few minutes. Initial setting happens at around the 10-minute mark, but the actual usable working time is considerably shorter. For simple repairs (filling a crack, closing a joint) that's plenty. For jobs where you need a longer open time, the Gomagom 29 is the right choice. If you're tackling a larger repair with the 31, mix the putty in small batches and work section by section rather than mixing all 30 g at once.

Can it be painted after it sets?
Yes. After full curing (it's best to wait 1–2 hours for delicate work) the hardened material accepts acrylic paint, enamels, and the usual modelling finishes. We recommend sanding the area first to blend it with the rest of the printed part, and applying a primer if you're going for a detailed final finish.

Is it waterproof once cured?
The manufacturer lists swimming pools and pipework among its typical applications, which confirms water resistance after full cure. This makes it suitable for repairs on printed parts that will be exposed to moisture (vases, plant pots, 3D-printed bathroom accessories). Full cure takes 24 hours, so it's best to wait until the following day before exposing the part to water.