How to Get Rid of Bubbles in Epoxy Resin: A Henkel Specialist's Emergency Guide

If you're reading this because you have bubbles in epoxy resin, here's the answer you need now: stop trying to pop bubbles after they form. Fix the process before you pour. Bubbles are created during mixing, pouring, or the early cure window. Once the epoxy gels, the only reliable fix is to grind it out and re-pour. The first 10 minutes matter more than anything after that.

I'm a technical service specialist at an industrial coatings distributor. For the last six years, I've handled emergency calls for customers who run manufacturing lines, fabrication shops, and construction crews. Last quarter alone, I coordinated 47 rush orders with a 95% on-time delivery rate. When I say emergency, I mean a call at 4 PM asking for product by 7 AM.

This is a conclusion-first guide. If you only read the next two sections, you'll know what to do. Then I'll explain why I trust these fixes, where they come from, and when they don't apply.

How to Get Rid of Bubbles in Epoxy Resin: The 4-Step Method

Work through these steps in order. Don't jump to step three.

1. Warm your resin and hardener before mixing. Heat doesn't make bubbles disappear, but it lowers the viscosity so the bubbles you do introduce can rise. Put the sealed bottles in warm water at 55-60°C (130-140°F) for 10-15 minutes. Don't overheat; you'll shorten your pot life.
2. Mix slowly and scrape the sides. Fast mixing folds air in. Use a flat spatula, mix for at least two minutes, and scrape the bottom and sides repeatedly. The goal is a homogenous mix, not a froth.
3. Pop surface bubbles with heat before gel time. A heat gun or propane torch passed quickly over the surface bursts the bubbles. Keep the heat source moving; one spot too long can initiate a localized cure. If you don't have a heat gun, a long-nose butane torch works on small parts, but keep it moving.
4. Use vacuum degassing for zero-void work. If you're casting or potting where internal bubbles are unacceptable, a vacuum chamber is the only reliable route. As of Q1 2025, a benchtop unit costs less than a single scrapped production batch.

The question isn't how do I get rid of bubbles? It's what in my process is creating them? Most of the failures I see are cold resin, aggressive mixing, and pours thicker than 10 mm. The material wasn't bad. The process was.

Here's the thing: most bubble problems I see are not from bad resin. They're from cold resin, fast mixing, and pouring too thick. Slow down those three steps and you'll eliminate most of the bubbles before they appear.

Why I Learned This the Hard Way

Until March 2024, I didn't fully appreciate how much a failed epoxy pour can cost a producer. A customer called at 5 PM on a Friday because a production fixture was full of bubbles and had to be recast by Monday morning. We arranged a vacuum degassing setup, got the recast done, and the part passed. But the customer lost two full production days. That lost time was worth more than the epoxy.

Honestly, I'm not sure why some shops still mix epoxy by eye. My best guess is habit. But slow mixing, a thermometer, and a heat gun are not expensive. The alternative is grinding and re-pouring, which always costs more.

Coatings Failures Aren't Always the Coating

When someone asks about Henkel functional coatings products, they're usually asking about the engineered layer between the substrate and the environment. That includes pretreatments like Bonderite, sealants like NP 1, and the topcoat. The mistake is treating functional coating as one product.

A platinum powder coating is a good example. It can look perfect out of the oven and still fail weeks later if the pretreatment under it wasn't right. I've seen a platinum powder coating delaminate after salt spray testing because the line rushed the wash stage. The coating wasn't the problem; the process was.

Henkel Supplier Portal Login: The Emergency Hail Mary

When I'm triaging a coatings failure, I don't email a sales rep. I search for supplier portal Henkel login, pull the technical data sheet, and check the cure schedule in the SDS. It sounds mundane, but as of Q1 2025, that portal has saved me from guessing more times than I can count. The portal is free (which, honestly, more people should use). Once you're logged in, search by product code, not by name. Searching for 'NP 1' returns the right SDS; searching for 'sealant' returns dozens of results. That seems small, but in an emergency it saves hours.

For example, in March 2024, a fabricator called at 4 PM needing 30 cartridges of Henkel NP 1 sealant by 7 AM the next morning for a roof panel installation. Normal lead time was three days. We used the Henkel supplier portal to confirm the product code and batch status, paid $240 in overnight freight, and it arrived at 6:40 AM. I approved the freight rate and immediately second-guessed whether a local pickup would have been cheaper. Didn't relax until the sealant arrived and the installer confirmed the batch was good. Missing that deadline would have triggered a $50,000 penalty clause.

NP 1 Sealant: One Product I Actually Stock

NP 1 sealant is a one-component polyurethane sealant that works well for low-slope roofing, siding, concrete joints, and a lot of metal fabrication. But here's the honest limitation: NP 1 isn't for everything. If you need a sealant for exterior glass glazing that will see continuous UV, a silicone will often outlast it. If the joint has high movement, check the movement rating before assuming. It's a great product for the right joint. It's not a universal answer.

If the Epoxy Is Already Cured

If the part is already hard and you're staring at a surface full of pinholes, you have two options. For a cosmetic piece, sand the surface to open the bubbles, clean with isopropyl alcohol, and apply a thin flood coat of the same resin. Let it cure and sand again. That will fix pinholes. But for a structural piece, a flood coat is not a repair. You need to know the void depth. If bubbles are deep enough to compromise the cross-section, the part goes in the scrap bin or gets sent to an engineer for evaluation.

One more tip: check your shop temperature. Epoxy cure is a chemical reaction. A colder shop means a longer open time and more time for bubbles to rise. A warmer shop means a shorter window. The SDS tells you the recommended temperature range; use a thermometer, not a guess.

When Not to Trust This Advice

Now for the boundary conditions, because the last thing I want is for you to read this, make one change, and assume all problems are solved.

• If your epoxy has already gelled, don't try to heat bubbles out. You'll only accelerate the cure and create more voids.
• If you're using a different brand or chemistry, verify the cure schedule on the SDS. The 4-step method works for most two-part epoxies, but not all.
• If you're re-coating a certified part or a surface under warranty, contact the coating supplier before you grind or re-pour. I've seen warranty claims voided by well-intentioned repairs.
• If the part is structural, get an engineer involved. A cosmetic bubble fix is not the same as a structural repair.

One more standard that matters: if you're matching a platinum powder coating to a brand color, ask for the Delta E number. Pantone's Color Matching System guidelines use Delta E < 2 as the tolerance for brand-critical colors. A Delta E of 2-4 is noticeable to trained observers; above 4 is visible to most people. If your coating supplier can't give you a Delta E, you're flying blind.

This advice was accurate as of Q1 2025. Prices, freight lead times, and product availability change, so verify current details through the Henkel supplier portal or your local rep before you commit to a deadline.