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Several epoxy coasters, made using wood and epoxy with a turquoise tint.

Primaloc Guides: How to Sand Resin Art

Creating resin art can be a very satisfying experience. Self-expression, the chance to experiment, and the opportunity to make something that someone else would value—whether as a gift or something to purchase—can make the whole process feel very worthwhile.

When it comes to crafting your own works, it's hard not to make a mistake or two every now and then. Epoxy may be relatively easy to work with, but it does need a little precision to achieve ideal results.

When your project doesn't turn out quite the way you want it, perhaps because it has some surface-level blemishes or imperfections, or maybe a few bubbles that you forgot to burst, it can feel like a complete waste. But that doesn't have to be the case.

Epoxy resin art with exterior flaws can be sanded down to restore it and provide a smooth, pleasing surface.

What Does Sanding Do?

Sanding is a technique in which an abrasive material is rubbed against the surface of another material to smooth out that material's surface and reduce or remove unwanted protrusions, scratches, or various other blemishes that seem to detract from the function or appeal of an object.

In the case of epoxy resin works, sanding allows you to smooth out the surface after something has gone wrong. It could be a light bit of damage years down the road, or it might be the result of a mistake during the pouring or curing process that didn't get addressed in time.

Regardless, sanding can help fix problems and prepare an epoxy surface for certain techniques—e.g., a refresh coating—when the epoxy has already cured solid.

How Is Sanding Accomplished?

Typically there are two ways to sand something: either by hand or by using a power sanding tool.

For this article, we'll be explaining how to sand by hand, as most resin art will be either small or have a peculiar shape that isn't conducive to the large flat discs of a power sander. Manual sanding also gives you more control over your sanding, so that you don't accidentally overdo when working with nuanced shapes and contours.

What's Better, Dry Sanding or Wet Sanding?

Manually sanding includes two categories of sanding techniques. The first is dry sanding, and the second is wet sanding.

Dry sanding involves rubbing your sanding material against a completely dry surface. It takes a little less effort than wet sanding, but generates "sanding dust" that can be scattered into the air, circulating until it settles.

Wet sanding, on the other hand, uses water to dampen your sanding abrasive or target surface to prevent the dust from spreading, making it safer and easier to clean up. Wet sanding uses particular abrasives that support the moisture element. These can often be reused after washing them and allowing them to dry.

For this guide, we'll use wet sanding, which we recommend over dry sanding in most cases.

Epoxy coasters of different colors, made with resin.

Sanding Resin Art: What You'll Need

The first thing to understand is that manually sanding epoxy resin can be quite intensive. Epoxy resin is valued for its incredible tough surface, and unfortunately that feature works against you when you're attempting to sand it. As a result, it will take some real time and effort for larger or more complex pieces of resin art.

Nonetheless, sanding epoxy is entirely feasible, and you can accomplish it over multiple sessions—there's no need to get the whole process done in one go (unless you're working within a tight timetable).

Here's what you'll need to get started:

  1. Sandpaper (400, 600, 800, and 1000-grit): This is the core component to the sanding process. It's good to have each of these, as we'll start low and gradually move to the higher grits to give your surface a finely-sanded finish.

    Choose a sandpaper that's labeled as wet/dry.

  2. A Suitable Mask (N95 or KN95 Recommended): This will protect your lungs from any dust. Though wet sanding makes it almost a non-factor, we still like to recommend this precaution tot anyone who might have respiratory issues.

  3. Water: You just need a small amount in a cup or spray bottle. It's solely for wetting the surfaces of your abrasive or epoxy finish.

Optional Tools for Sanding Resin Art:

  1. Ultra Fine Wet/Dry Sanding Pads: These are thicker than sandpaper, making them easier to grip and hold while still conforming to the surface of the epoxy you'll be sanding. They're not essential, but we recommend them.
  2. A Sanding Block: For flat resin surfaces or larger rounded surfaces, you can use a sanding block to shorten the time sanding takes. Sandpaper can be attached to a sanding block to give you a much better grip and allow you to apply higher, more even pressure to your surface as you sand it down.

Setting Up Your Workspace

Once you have what you need, you should choose a location to do your sanding.

A sturdy surface you can lean on that won't wobble or move will enable you apply more force while sanding. Though some people prefer to stand for this, it's usually easier and more comfortable to be sitting as you work your way through the process.

Organize your space so that all the tools are where you can reach them. One you've done that you're ready to sand.

A piece of epoxy art, made with epoxy resin and two Pigmently dyes.

How to Sand Resin Art

From here we 'll be sanding the epoxy surface. This is a good time to put on your mask.

Step #1: The 400-Grit Sandpaper

We'll start with the 400-grit sandpaper; moisten it and begin applying force to the resin while rubbing it in circular motions. Back-and-forth motions will work as well, if you can't get a good flow going (perhaps due to the shape of it).

Shift to a new angle occasionally. The intent here is to smooth out your surface, which you'll be able to see and/or feel. The time it takes can vary, so just check the surface with your fingers now and then if you can't tell by looking.

While sanding, look at it from different angles to see if the light reveals any obscure blemishes that you need to work on.

If you need to apply more pressure to a tough spot, you can place the sandpaper (face up) on your workspace surface, and then just rub the resin piece over it in circular movements. This is a bit more awkward, but allows you to deliver greater force to a stubborn area.

At any point, you can use a clean cloth to wipe away any dust, then feel the surface to determine if it seems right.

Step #2: The 600-Grit Sandpaper

After you've done what you can with the 400-grit sandpaper, it's time to move to the 600-grit. The process is the same, more or less, so just focus on getting the surface even smoother.

Step #3: The 800-Grit Sandpaper

The super-fine 800-grit is our third grit size for this process. Once again, you'll use smooth, circular motions to rub the surface until it's even smoother.

Essentially, what you're doing is replacing each set of sanding scratches with something even finer and smaller—400 to 600, 600 to 800. Eventually the grit is so high that the scratches are imperceivable, barely even there.

And that's why we next go to the 1000-grit.

Step #4: The 1000-Grit Sandpaper

This is the final step in the resin art sanding process. There's nothing more to do here than sand away until you're satisfied.

If any part of your surface is not becoming smooth enough, it means you're not applying adequate pressure or it needed more time at the previous grit.

...And Then You're Done

After you've finished sanding, you can clean the surface off and appreciate the work you've put in.

Primaloc Epoxy: Premium Epoxy for Premium Results

When it comes to epoxy resin, Primaloc Epoxy gets the job done. Our epoxy resin is premium-grade and cures clear and strong, with high performance in every category.

Epoxy resin can be beautiful, strong, and long-lasting—which is why you shouldn't compromise on quality. With Primaloc Epoxy Resin, you get the ultimate finish in durability and visual appeal.

Protect your surfaces by giving them a rock-solid epoxy finish. Choose strong. Choose reliable. Choose Primaloc.


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