How to File Resin: Start with Coarse Grit and Progress Gradually

Q: Step-by-Step Approach

Begin with coarse grit (around 80–120 grit for rough work like shaping edges on large pours or removing visible layer lines on 3D prints). Move to medium grit (180–240 grit) to start reducing the marks left by the coarser paper. Finish with fine grit (400–1000+ grit) for a smooth, ready-to-polish result—or even higher for an ultra-clear surface on artistic projects like those using Art Pro Epoxy Resin . Always use light, even pressure and, where possible, wet sand the resin to help avoid clogging and keep dust to a minimum.

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Start with Coarse Grit, Progress Gradually: Filing Resin Properly

Achieving a smooth and polished finish on cured resin requires using abrasives in a particular sequence. Start with a coarse grit, then move through finer grades for the best results—whether working on deep pour tables, 3D prints, or artistic coatings.

Why Start Coarse and Go Finer?

Cured resin is quite hard, so the initial filing or sanding is best done with a coarse grit. This quickly levels imperfections or uneven seams formed during casting or coating. Once the main high spots are removed, gradually switching to finer grits refines the surface, reduces visible scratches, and achieves that sought-after glass-smooth finish.

Step-by-Step Approach

Begin with coarse grit (around 80–120 grit for rough work like shaping edges on large pours or removing visible layer lines on 3D prints).
Move to medium grit (180–240 grit) to start reducing the marks left by the coarser paper.
Finish with fine grit (400–1000+ grit) for a smooth, ready-to-polish result—or even higher for an ultra-clear surface on artistic projects like those using Art Pro Epoxy Resin.

Always use light, even pressure and, where possible, wet sand the resin to help avoid clogging and keep dust to a minimum.

Choosing the Right Resin for Filing and Finishing

Some resins are easier to file and finish than others. For deep pour projects such as river tables, a product like EpoxyTable 5-Five is designed for clarity and mechanical resistance, resulting in a surface that responds well to careful filing and subsequent polishing. Fast-coating solutions like 3D Finish are ideal for 3D prints where retaining detail and a clean finish is important.

When This Matters

Following this progressive grit approach is especially important for large, functional resin projects—like tabletops and coasters—where a professional finish is expected. It is also vital for decorative surfaces and 3D printed models where a pristine end result can make all the difference.

Related guides

How Do You File Resin

A careful progression from coarse to fine abrasives ensures every resin project—from deep pour tables to custom 3D prints—achieves a refined surface. For more detail on finishing techniques and suitable products, visit our main page on how to file resin.