The pour is done. The resin is cured. The form is off. And now you're staring at a surface that looks nothing like the glassy tabletop you imagined — it's dull, scratched from flattening, and the edges are rough.
This is normal. The finish is built in this final stage, not during the pour.
Finishing an epoxy table is a methodical process of progressive abrasion followed by polishing. Done correctly, the result is a surface so clear and reflective it looks like glass poured over wood. Done incorrectly, you'll end up with haze, swirl marks, or a finish that looks great in the shop and dull under home lighting.
Here's how to do it right.
Step 1: Start Flat
Before you touch sandpaper, the surface must be flat. Any low spots, high spots, or ridges from the flattening process will telegraph through every subsequent grit and show up in the final polish.
If you haven't already flattened with a wide-belt sander, drum sander, or CNC router sled, do that first. The goal is a single continuous plane across both wood and epoxy — no steps, no waves, no tool marks deeper than 80 grit can remove in a reasonable amount of time.
Check flatness with a straightedge in multiple directions and in raking light. Fix any issues before proceeding.
Step 2: The Sanding Progression
Sanding epoxy is different from sanding wood. Epoxy is harder, loads sandpaper faster, and requires more passes per grit to fully remove the scratches from the previous grit. Rushing the progression is the single most common finishing mistake.
The Full Grit Sequence
Coarse (machine sanding — random orbital or belt):
- 80 grit — removes flattening marks and levels the surface
- 120 grit — removes 80-grit scratches
- 180 grit — removes 120-grit scratches
- 220 grit — removes 180-grit scratches; surface begins to look uniform
Fine (machine or hand sanding):
- 320 grit — transitions from cutting to refining
- 400 grit — surface starts to develop a slight sheen
- 600 grit — scratches become very fine; wood grain pops
Ultra-fine (hand sanding or finishing pad):
- 800 grit
- 1000 grit
- 1500 grit
- 2000 grit
- 3000 grit — surface is now hazy but scratch-free at the macro level
Rules for Every Grit Change
- Wipe the surface clean between every grit with a tack cloth or damp rag. Coarse grit particles left on the surface will scratch through finer paper.
- Inspect in raking light before moving on. Hold a work light at a low angle and look across the surface. Every scratch from the previous grit must be gone before advancing.
- Sand in consistent passes. Random orbital sanders work well through 400 grit. Above that, switch to hand sanding with a flat block to avoid swirl marks from the orbital's pattern.
- Don't skip grits. Jumping from 220 to 800 doesn't save time — it creates scratches that 800 can't remove, and you'll have to go back.
Wet vs Dry Sanding
Above 400 grit, wet sanding becomes an option. Wet sanding uses water or a lubricant to float away swarf (the fine particles removed by the abrasive), preventing loading and reducing heat.
Advantages of wet sanding:
- Sandpaper lasts significantly longer
- Reduces heat buildup that can soften epoxy
- Produces a more consistent scratch pattern
Disadvantages:
- Messier
- Water can raise wood grain if it penetrates unsealed areas
- Requires waterproof sandpaper (wet/dry paper)
For most builders, dry sanding through 400 and wet sanding from 600 upward is a practical approach.
Step 3: Polishing
After 3000 grit, the surface is scratch-free but hazy. Polishing removes that haze and brings the epoxy to a high-gloss, mirror finish.
Polishing Compounds
Polishing compounds are abrasive pastes that work like very fine sandpaper — they remove the micro-scratches left by 3000 grit and replace them with scratches too small to see individually, which the eye reads as gloss.
Two-stage polishing is standard:
- Cutting compound (heavy polish): Removes 3000-grit haze and levels the surface. Use with a foam cutting pad on a dual-action (DA) polisher or rotary buffer.
- Finishing compound (fine polish / glaze): Removes swirl marks left by the cutting compound and brings the surface to maximum gloss. Use with a soft foam finishing pad.
Recommended approach:
- Apply a small amount of cutting compound to the pad
- Work in overlapping passes at medium speed
- Wipe off residue with a clean microfiber cloth
- Inspect in multiple lighting conditions
- Repeat with finishing compound
Machine vs Hand Polishing
A DA polisher or rotary buffer produces dramatically better results than hand polishing and is worth the investment if you plan to build more than one table.
DA polisher: Safer for beginners — the dual-action motion reduces the risk of burning through the surface. Slower cutting action.
Rotary buffer: Faster cutting, higher heat generation. Requires more experience to avoid burning or hazing the surface.
Step 4: Edge Treatments
The edge profile of an epoxy table is a design decision that significantly affects the finished look — and it needs to be decided before final polishing, since edge work creates dust that will contaminate a polished surface.
Common Edge Profiles
Flush / Square Edge
The simplest option — the top surface meets the side at a 90° angle. Clean and modern. A very slight break (one or two passes with 220 grit) prevents chipping without changing the visual profile.
Chamfer
A flat angled cut (typically 45°) along the top edge. Adds visual interest and eliminates the sharp corner. Works well on both wood and epoxy sections.
Roundover
A curved profile along the top edge, created with a router roundover bit or hand sanding. Softer and more organic — pairs well with live edge designs.
Waterfall Edge
The most dramatic option — the tabletop material continues vertically down the side of the base, creating the illusion that the wood and epoxy are flowing continuously from horizontal to vertical. Stunning when executed well.
Live Edge (No Treatment)
On the wood sections, the live edge is often left natural — bark removed, surface sanded, but the organic profile preserved. The contrast between the raw wood edge and the polished epoxy river is a defining feature of the river table aesthetic.
Finishing the Edges
After shaping, sand the edges through the same grit progression as the top surface. Epoxy edges polish to the same glassy finish as the top — don't stop at 220 and call it done.
Step 5: Protective Topcoats (Optional)
A fully polished epoxy surface is already durable and water-resistant. Whether to add a topcoat depends on the use case and the look you want.
Topcoat Options
Hardwax Oil (for wood sections only)
Not suitable for epoxy — won't bond properly. Use on the wood portions of the table for a natural, penetrating finish that's easy to repair.
Water-based polyurethane
Low yellowing, fast dry time, good durability. Apply in thin coats with a foam roller or quality brush. Sand lightly between coats with 320 grit.
Oil-based polyurethane
More durable than water-based but adds a warm amber tone. Better for tables that will see heavy daily use.
UV-stable varnish
Best choice for tables near windows or in outdoor covered spaces.
Applying a Topcoat Over Polished Epoxy
If you've polished to a high gloss and want to add a topcoat, you must scuff the surface first. Topcoats won't bond to a mirror-polished surface — lightly sand with 320 grit to create mechanical adhesion, then apply the topcoat.
Common Finishing Mistakes
Swirl marks in the final polish
Caused by switching from a cutting pad to a finishing pad without fully removing cutting compound residue. Fix: re-apply cutting compound, work more slowly, and follow with finishing compound.
Haze that won't polish out
Usually means you didn't fully remove the scratches from the previous grit before moving on. Go back two grits and work through the sequence again.
Orange peel texture
A dimpled surface texture caused by applying a topcoat too thickly or in conditions that are too warm. Sand flat with 400 grit and re-apply in thinner coats.
Dull spots after polishing
Often caused by contamination — oil from hands, silicone, or wax residue. Clean the surface thoroughly with isopropyl alcohol before polishing.
The Finished Result
A properly finished epoxy river table is one of the most visually striking pieces of furniture you can own or build. The surface should be clear enough to read through, reflective enough to show the room above it, and smooth enough that running your hand across it feels like touching still water.
Getting there takes patience and the right sequence. But there are no shortcuts that produce the same result.
Built to a Flawless Finish — Every Time
At S and N Custom Works, every epoxy table goes through a full finishing process: staged sanding from 80 through 3000, machine polishing with cutting and finishing compounds, and edge treatment matched to the design. The result is a surface that's ready to anchor your room from day one.
Commission a custom epoxy table →
Want to see the finish quality up close? Get in touch — we're happy to share photos of recent builds.
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