PETG and PCTG are tough, chemical-resistant filaments. That's great for printed parts, but it also means some glues don't stick well, and the filament picks up moisture from the air faster than PLA. Here's what glue to use, how to dry PETG and PCTG, and how to store them so they print cleanly every time.
What's the Best Glue for PETG?
The two glues that work best on PETG and PCTG are cyanoacrylate (super glue) and two-part epoxy.
| Glue | Best for | Notes |
|---|---|---|
| Cyanoacrylate (super glue) | Small parts and tight-fitting joints | Fast and strong on clean, close-fitting surfaces. Gel versions are easier to control. An accelerator spray speeds up curing. |
| Two-part epoxy | Large, structural or load-bearing joints | Fills gaps and makes the strongest bond. Choose an epoxy rated for plastics. Slower to cure. |
| Plastic welding | Seams and repairs | Melt a strand of the same filament into the joint with a 3D pen or a soldering iron with a dedicated tip. The joint becomes the same plastic as the part. |
| Hot glue | Temporary holds only | Peels off PETG easily. Not recommended for anything that needs to last. |
Does super glue work on PETG?
Yes. Super glue works well on PETG and PCTG when the surfaces fit closely and are clean. It's the quickest option for small parts, clips and repairs. For big parts or joints with gaps, use epoxy instead.
Can you solvent-weld PETG like ABS?
Not easily. ABS can be welded with acetone, but PETG and PCTG are much more chemical resistant, and acetone does very little. The solvents that do work on PETG are harsh and not worth the risk for most people. Stick with super glue, epoxy or plastic welding.
How to Glue PETG and PCTG Parts
- Test-fit first. Make sure the parts line up before any glue goes on.
- Scuff the surfaces. Lightly sand both mating faces with 120–220 grit sandpaper. PETG's smooth, glossy surface gives glue little to grip.
- Clean them. Wipe the surfaces with isopropyl alcohol to remove dust and oils, and let them dry.
- Apply a thin layer. Use a thin bead of super glue, or a thin coat of mixed epoxy on both faces. More glue doesn't mean a stronger joint.
- Clamp and wait. Hold the parts together with clamps, tape or rubber bands. Let super glue set for a few minutes and fully cure overnight. Follow the epoxy maker's cure time.
Tip: design glued joints with pins, slots or overlapping surfaces. More surface area means a much stronger bond than a flat butt joint.
Why Dry PETG and PCTG?
PETG and PCTG slowly absorb moisture from the air. A sealed spool from us is ready to print. Our filament ships sealed with desiccant. But a spool left out for days or weeks can pick up enough moisture to cause problems.
Signs your PETG is wet
- Popping, crackling or hissing sounds from the nozzle
- More stringing and oozing than usual
- Bubbles, rough spots or a dull, fuzzy surface
- Weaker parts and poor layer adhesion
How to Dry PETG and PCTG Filament
| Material | Drying temperature | Time |
|---|---|---|
| PETG / PCTG | 65°C | 8–16 hours |
| PLA | 45–50°C | 4–6 hours |
| ABS / ASA | 80°C | 4–8 hours |
| Nylon | 85°C | 12–24 hours |
- Use a filament dryer or a printer or AMS unit with a built-in drying function. They hold a steady low temperature, which is what you need.
- Be careful with ovens. Most kitchen ovens can't hold 65°C accurately and can overshoot. That softens the spool and can fuse the filament together. Use one only if you've checked it with an oven thermometer.
- Don't go hotter to save time. Going above these temperatures can warp the spool and make the filament stick to itself.
- Time depends on how wet it is. A spool left out for a few days may only need the short end of the range. One that's been out for weeks may need the full time.
You can also print straight from a dryer. Feeding PETG from a heated dry box keeps it dry through long prints.
How to Store PETG and PCTG
- Keep spools in a sealed bag or airtight bin with desiccant when you're not printing.
- Use a dry box or a humidity indicator card to see when the desiccant needs replacing or recharging.
- Keep spools out of direct sun and away from heaters.
- Reseal the original bag. Our bags include desiccant, so even one that has lost its vacuum seal keeps the filament dry.
PETG Glue & Drying FAQ
What's the strongest glue for PETG?
A two-part epoxy rated for plastics, on sanded and cleaned surfaces. For small parts that fit tightly, super glue is nearly as strong and much faster.
Does Gorilla Glue or super glue work on PETG?
Cyanoacrylate super glues, including the major brands, work well on PETG when the surfaces are scuffed and cleaned. Foaming polyurethane glue is less reliable on smooth plastic.
Can PETG be glued to PLA?
Yes. Super glue and epoxy both bond PETG to PLA. Prep both surfaces the same way: sand, clean, then glue.
How long does it take to dry PETG?
About 8–16 hours at 65°C, depending on how much moisture it has absorbed.
Can I dry PETG in the oven?
Only if your oven holds 65°C accurately. Many ovens overshoot at low settings, which can soften the spool and fuse the filament. A filament dryer is safer.
Does PCTG need to be dried like PETG?
Yes. PCTG is a copolyester like PETG and absorbs moisture the same way. Dry it at 65°C for 8–16 hours. Learn more in What Is PCTG Filament?
Shop PETG PRO and PCTG PRO filament, made in Indiana, USA, or read PLA vs PETG to pick the right material.