What happens if you don’t sand between coats of epoxy?

Epoxy is a type of glue that can be used to bond two or more surfaces together. Epoxy is often used in construction and industrial applications, but it’s also popular for woodworking projects because it dries quickly and doesn’t require sanding between coats.

Epoxies are composed of two parts: the resin and the hardener. The resin acts as an adhesive to hold the two pieces together; it also provides strength to whatever object you’re working on.

The hardener forms tiny crystals when mixed with the resin, which helps strengthen its bond once it cures.

What happens if you don’t sand between epoxy coats?

You can get away with it, but you’ll be paying for it later. Specifically, there’s a good chance that:

  • your final finish will have an uneven look
  • air bubbles will form under the surface layer of epoxy, resulting in a non-uniform appearance
  • the strength of your final product won’t be as strong as what you intended for it to be because air bubbles act like little weak points in your material’s structure (think about how a balloon pops)

Can you layer epoxy without sanding?

If you don’t sand between coats of epoxy, you may see brush strokes or the epoxy might not adhere properly. It also may not cure properly and might be weaker than it should be.

However, if you’re in a hurry to finish a project and can’t wait for more sanding time (or if the last coat of epoxy is already on), here are some tips for getting your finish to stick:

  • Make sure the surface is completely clean before applying another coat of epoxy
  • Apply several thin layers rather than one thick layer
  • Let each layer dry before applying another one

Can you apply a second coat of epoxy without sanding?

For most epoxies, you can apply a second coat without sanding. However, there are a few factors to consider:

  • Make sure the previous coat is fully cured before applying another one.
  • If you are unsure whether or not it’s dry enough, sand it lightly with 100-grit sandpaper before applying more epoxy.

Can you sand epoxy after 24 hours?

You can sand epoxy after 24 hours, but you’ll need to be careful. Because it’s not a true paint and requires a curing period, it won’t adhere well to the surface. If you try to sand too early and don’t take special care when doing so, your epoxy might come off with the sandpaper instead of leaving behind a smooth finish.

When it comes time to sand your freshly applied epoxy with 120-grit paper (or whatever grit is appropriate for your project), do it in small patches—about 1 foot square at most—and gently rub against the wood grain with very little pressure at first until any rough spots are removed. Don’t press so hard that you run through the film; if this happens, start over again and wait longer before applying more coats of epoxy!

How long should epoxy dry between coats?

In general, the more coats of epoxy you apply and sand between each coat, the smoother your finished surface will be. The tradeoff is that it takes longer to apply all those coats!

1 hour between coats: If you want minimum sanding time, then allowing 1 hour between each coat should work fine. This will give you enough time for most types of epoxy to cure before applying another coat.

You may want or need more time depending on what type of project you’re working on—for example, if there are large areas where paint needs to be removed prior to applying an epoxy coating (like when covering an oil-based finish).

3 hours between coats: If you have a moderate amount of sanding required after every application (e.g., small amounts), then waiting 3 hours before applying another coat could work well for your project. Again though—for big projects that require lots of prep work before starting with an epoxy primer/finish such as removing oil-based finishes from wood surfaces first) then try waiting 8 hours instead!

Just make sure everything is fully cured first so that no curing issues arise later down the road when trying out other techniques such as scraping back through some layers in order to remove excess material left behind by previous steps taken during application process which might disrupt the overall effect desired outcome being achieved.”

Can you pour epoxy over cured epoxy?

Theoretically, yes—but it’s not recommended. The chances of bubbles forming are much higher, and if you’re using a hardener, you’ll need to sand the surface to eliminate any imperfections and then apply new coats of epoxy.

If you do pour-over cured epoxy, be sure to sand it very carefully afterward, as curing can change the properties of your previous layers!

Why is my epoxy bumpy?

If you’ve ever noticed that the finish on your epoxy is bumpy, it’s most likely due to one of the following reasons:

  • Bubbles in the epoxy. This happens when there’s too much hardener in the mixture. If this happens, you can easily pop out any bubbles by tapping them with a piece of wood or metal until they’re gone.
  • An uneven surface. If your epoxy has cured and still has an uneven surface, this means that it wasn’t mixed well enough before applying it (or maybe even after). It might also mean that dirt or dust got into your mixture during application, so make sure to wipe down everything thoroughly before painting over it again!
  • The wrong mixing ratio/temperature/amounts used throughout painting process

Can you spot fix epoxy?

If you do get a bit of epoxy on your surface and it’s not too big, you can try to remove it with a razor blade. Scrape off as much as possible, then sand down the area so there are no bumps or ridges before doing another coat of epoxy. Remember that if you don’t sand between coats of epoxy, it will never bond properly!

If you need to add more coats than usual because of mistakes like this one—or if you made other errors in applying the first coat—you may want to start over completely.

Slight mistakes will be easily visible when they’re layered over top of each other: even though they’ll probably not be noticeable at all once the second coat is dried and sanded (and possibly even after subsequent applications), they’ll stand out until then.


  • Sanding epoxy is easy and rewarding, but it’s best to do it between coats. After 24 hours, you can sand your epoxy without damaging the surface if you’re careful.
  • If you want to apply another coat of epoxy before the first one is fully dry, go right ahead! Just be sure to wait until the first layer has hardened up enough so that it won’t get pulled off by your rubbing pad when you sand between coats.
  • It’s possible to layer epoxy without sanding in between each layer, but this process isn’t recommended as it may result in a weaker bond between layers. Additionally, some people find that they don’t like the way their paint job looks after this type of layering because there are visible ridges where new layers meet older ones (a process known as “orange peel”).
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Martin Flood

Martin Flood has been working in the construction industry for over 20 years as a general contractor with expertise in remodeling projects that are large or small. He has furthered his career by specializing in epoxy resin flooring, providing excellent service to both commercial and residential clients. Martin’s experience enables him to offer professional advice on how to choose the right type of project based on your needs and budget.

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