How to Polish Epoxy Resin for a Clear Finish

Most of the woodworkers and artists have worked with epoxy resin before. You’ve probably seen that after curing, release from a mold or noticed that the result is not as planned, it does not have a crystal-clear surface, but a matte and dull or contain haze finish. Thankfully, there is a simple method to make your resin piece surface shine and give a high gloss finish. It’s a very simple technique that ensures a perfect project result.

Whether you’ve finished sanding your project surface or looking for a high gloss, deeper or more shiny finish, learn how to polish epoxy resin after sanding and use these tips and tricks on your next epoxy resin project!

Above: Epoxy resin table polished and made out with Baltic Day mica powder pigments for the river inlays on a table tops, by our client @refinednaturesantafe

Getting Started – Sanding of Epoxy Resin

Let’s say you poured your epoxy resin and after 24 hours you noticed some imperfections that you want to get rid off. Sanding and polishing are two most important steps to take care of your surface. It starts with wet sanding. Use a wet sanding sandpaper. This wet standing technique involves carefully sanding from grit 120 to grit 1500. This work can be done by your hands or special tools like electric sander. Keep in mind, to always clear these away before you start polishing!

While sanding resin removes any excess surface and smoothens your DIY project surface, polishing will help you to obtain a shiny finish. Resin objects such as jewelry, resin art, river tables, floors, wooden cutting boards, lamps or any other wooden project are suitable for polishing after curing.

Sanding epoxy resin surface is preparing the resin for the next step – polishing. Sanding process also reduces dust formation. Let’s see what we need and how to do it properly.

Above: Epoxy resin polished with electric sander and made out with Baltic Day pigment powder for the metallic efect on top, by our client @refinednaturesantafe

Here are the tools we recommend to you in order to get started and help the sanding and polishing process go smother: Sandpaper from grit 120 to grit 1500 ;  Soap ; Sanding Block ; Water ; Remover compound ; Buffing products ; Wax

We sanding reduces clogging of the sandpaper or sander, removes blush and reduces dust formation. The surface will cure fully in 24 – 48 hours.

A Step by Step Sanding Process:

1. Use soap and warm water to clean the surface
2. Fill a bucket with water
3. Dip the sandpaper or sander into the water
4. If you need to add more water on the surface, apply some water by hand
5. If you notice any milky water, wipe it off with a cloth
6. Make sure that the traces become less the finer with each change of size grit
7. The scratches should be visible from the previous sanding process
8. Remove the water out from the surface
9. Dry off the resin piece and apply the polishing compound

Recommended Epoxy Resin Colorants 

Baltic Day are experts in producing the best epoxy resin and colorants and therefore also known, how to treat the cured resin perfectly to get the best out of it! Crystal clear resin is perfectly suitable for all resin art applications, polishing by machine or by hand.

Instructions – How to Polish Resin

The polishing process is not hard as it looks like, it involves cleaning, sanding, and applying a polishing compound. However you should be extremely careful! These simple factors as polishing paste used, polishing sponge or the number of revolutions used must be considered.

What to use to Polish Epoxy Resin:

1. Polishing compound
2. Microfiber dust cloth
3. Power Drill
4. Polishing Machine / Dremel
5. Buffing Wheel

For small objects, use a standard drill with a polishing attachment. There are polishing discs in various sizes which are suitable for any mini object.

For large objects or surfaces, it is recommended to use polishing machines or dremel. Different polishing sponges can be attached for a variety of projects.

Tutorial – How to Polish Epoxy Resin

1. After sanding, apply the polishing attachment onto the drill bit.
2. To set up the polishing attachment, tub the compound into a small piece of resin using a cloth. Hold the disc against a square object.
3. Use a polishing tool ( paste or buffing wheel ) to polish larger pieces.
4. Use a microfiber cloth to get a beautiful and glossy finish.
5. If necessary, repeat this process again.

Above: Epoxy resin table polished and made out with Baltic Day mica powder pigments, by our client @refinednaturesantafe

It’s comfortable to polish epoxy resin by hand. For this type or polishing, you will need: colorless polishing paste, water, cloth and a piece of wood:

1. Apply colorless polishing paste to the cloth.
2. Rub the cloth slowly ( with a little pressure ).
3. For the straight surfaces or edges, wrap the block with a microfiber cloth.

If you have a smaller object such as jewelry, charms or small boards, using a Dremel tool is a great choice. Do not buff any one area for more than 2-4 seconds ( avoid using pressure ). If needed, finish the polishing by hand.

If you have a large object such as resin table tops, floors, large cutting boards, it is recommended to use a polishing machine. These special machines move the polishing attachment eccentricity that makes great results.

Resin polishing is a must for obtaining a shiny and glossy surface of your artwork made of epoxy resin. Make sure that your workpiece has been prepared for polishing. If you don't do it carefully, the surface will show scratches which cannot be removed.

Something went wrong.. What Should I do?

Mistakes can happen all the time, even for the professionals! It is important to learn from these mistakes and keep moving forward! Common resin mistakes and how to fix it:

How to Remove and Prevent Tiny Bubbles?

Before working with epoxy resin, warm the resin and hardener at room temperature. Always mix resin mixture thoroughly for at least 5-7 minutes slowly, making sure to scrape the sides and bottoms of the mixing cup or bucket. If you pour epoxy into a mold to fast more small bubbles will arise, always pour very slowly.

A great tool to use is a heat gun or torch. It’s an easy technique that works very well! If you notice bubbles on already cured artwork, use a razor blade to pop the bubbles and mix these holes with an extra pour, wait for minimum 4-6 hours and reflood the surface. Check out our informative article on how to remove air bubbles from resin – How Do I Get Bubbles Out Of Epoxy Resin?

How to Fix Tacky/Sticky Resin

The main reason is caused by inaccurate measuring resin and hardener, or not mixing it thoroughly. Humidity, temperature of the resin and texture of the silicone mold are also important factors. To avoid this, make sure to work in humid conditions or at least room temperature. The mold should be completely clean and dry before pouring the resin mixture. Resin should be warm and mixed correctly ( as per manufacturer requirements ). If the resin is too cold, it will become more cloudy. After you purchase an epoxy resin kit, it is best to put it in a warm bath and let it warm for a minimum 10 minutes. If you still think that your epoxy resin is still cloudy, mix an extra amount of resin and use a paintbrush to paint a light layer over the top. Let it cure for 24-48 hours and wuolia!

Check out our another article – My Resin is Tacky – How do I harden Sticky Epoxy?

Share your own techniques and thoughts in the comment below!