How to Clean Syringes Used for Epoxy Resin

Co-authored by Dan Hickey

Last Updated: June 11, 2022 References

Buying art supplies can sure get expensive after a while. Wouldn’t it be great to reuse an epoxy resin syringe a few times? Good news—when you properly remove resin from a syringe, you can extend its life and use it for multiple projects! That’s why we’ve put together a handy guide to thoroughly cleaning out your syringe once you’ve dispensed your epoxy. If you’re excited to use some squeaky clean syringes on your next project, read on!

1

Put on a pair of disposable gloves.

Always wear protective gloves when you work with epoxy. Epoxy is an irritant that causes inflammation and skin damage. The solvents used to clean up epoxy resin can also enable your skin to absorb the resin if you’re not careful. Wear gloves to keep both substances off your skin.^{[1]
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- If you do get resin on your hands or skin, dissolve it away with a rag soaked in vinegar or use a waterless citrus-based hand sanitizer.^{[2]
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- A cotton ball soaked in acetone can remove resin from your skin as well. Make sure to wash your hands thoroughly afterward and moisturize the area.^{[3]
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2

Empty the syringe.

Push the plunger all the way into the barrel of the syringe to empty it. This will eject almost all of the remaining epoxy resin and make cleaning the syringe easier.^{[4]
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Research source} Eject the epoxy onto a sheet of parchment or wax paper and let it cure (harden) before throwing it away. It won’t stick to the paper, so just peel it off and toss it in the trash.^{[5]
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- If the resin and hardener can be emptied separately, store them for later use in their original container.^{[6]
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3

Wipe out the syringe, if possible.

Wipe out the barrel of the syringe with a paper towel or cotton swab. While the epoxy resin inside is still wet, pull off the plunger and wipe away as much liquid as possible from the sides of the barrel. The paper towel won’t stick until the resin begins to dry.^{[7]
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- Throw away the resin-y paper towels afterward.
- Some syringes are too small to wipe inside, and some don't have removable plungers. If so, don’t worry! The remaining steps will clean it sufficiently.

4

Fill the barrel with a solvent solution.

Replace the plunger and draw in a solvent solution through the needle. Effective solvents for epoxy resin are isopropyl alcohol (93% alcohol or stronger), acetone, paint thinner, or distilled white vinegar.^{[8]
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Research source} First, pour your solvent into a cup or dish. Then, push the plunger all the way forward, dip the needle into the solution, and pull the plunger back to draw in liquid until the barrel is full.^{[9]
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- Acetone and paint thinner are flammable and harmful when inhaled. Use these chemicals in well-ventilated areas away from heat sources or flames.^{[10]
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- Solvents work faster when they’re applied while the epoxy resin is still wet.

5

Wait up to 30 seconds.

Allow 30 seconds for the solvent to dissolve the epoxy resin. Lightly shake or tap the barrel of the syringe during this time to help loosen the resin. Be gentle so no liquid leaks out of the needle or joints of the syringe.^{[11]
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- Make sure only the inside of the barrel and needle are exposed to the solvent. Soaking or submerging your syringe in solvents will shorten its life dramatically.

6

Expel the solvent and resin.

Push the plunger in to empty the barrel of solvent and epoxy resin. Press quickly to apply more pressure and blast out the liquid.^{[12]
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Research source} Dispose of alcohol or vinegar solvents in a trash can or down a drain. Acetone and paint thinner are hazardous waste—empty the syringe into a secure metal container, double bag it, and throw it away to dispose of these chemicals.^{[13]
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7

Flush the barrel 2 to 3 more times.

Fill, shake, and flush the barrel with solvent to dissolve all resin. Usually, 2 or 3 more flushes will get the job done. Use fresh, unused solvent each time. This ensures any remaining epoxy will be thoroughly dissolved and removed before you rinse the syringe out.^{[14]
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8

Rinse out the syringe barrel.

Draw in hot, soapy water through the needle to rinse the solvent.^{[15]
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Research source} Shake and tap the syringe to swish the water around and collect any remaining solvent or resin. Eject your used water through the needle and repeat 2 or 3 more times (using fresh water each time) to thoroughly clean it.^{[16]
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- Use plain water (no soap) for your final rinse to remove soap residue.
- It’s important to remove all traces of the solvent since prolonged exposure can damage the syringe.

9

Scratch off dried resin.

Epoxy resin doesn’t bond to plastic, so dried bits can be popped off. After clearing out the wet resin, remove the plunger so you have access to the barrel. Use a small metal hook tool or tweezers to gently remove any hardened resin.^{[17]
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- Take care not to scratch or puncture the inside of the syringe.
- Exposure to the solvent will help loosen and partially dissolve hardened resin, making it easier to pop off.

10

Unclog the needle, if necessary.

Use a solvent or cleaning wire to remove dried resin from the needle. For a partial clog, flush the needle with solvent. You may have to remove the plunger and pour solvent into the barrel from the other end. For a total clog, use a thin wire or rod to dislodge the resin, then run solvent through the needle.^{[18]
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- Resist the urge to unclog the needle by forcing liquid through the needle with the plunger. The syringe may break under the pressure.

11

Dry the syringe.

Allow the syringe to air dry thoroughly before you use it again. If possible, take apart your syringe and lay the individual pieces on a clean cloth so they can dry faster. This ensures that no water will mix with your epoxy resin mixture during your next project.^{[19]
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