Surface finish guide

Finish Types

Choose by goal

Four finishing levels

Level 1

Production

Fast, functional parts with the natural manufactured surface.

Level 2

Clean

Support removal and cleanup for a neater functional component.

Level 3

Presentation

Sanding, polishing, paint, smoothing, or coatings for visible parts.

Level 4

Custom

Project-specific finishing based on appearance, environment, and function.

Finish library

Find the right surface finish

FDM + Resin

As Printed

Production

Typical look: Natural printed texture

Relative cost $

Lead time Fastest

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Why choose it?

Fastest and most economical option when function matters more than cosmetic appearance.

Things to consider

FDM layer lines or resin support/contact marks may remain visible. Small cleanup is still performed where required.

Best for

Prototypes, fixtures, hidden components, fit checks, internal parts.

Material compatibility

FDM: most materials • Resin: most standard and engineering resins

FDM + Resin

Support Removal & Cleanup

Clean

Typical look: Cleaner edges and contact areas

Relative cost $

Lead time Fast

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Why choose it?

Removes supports, strings, brims, sharp edges, and obvious manufacturing artifacts without full cosmetic finishing.

Things to consider

Minor witness marks can remain where supports were attached. Geometry can limit access.

Best for

Functional end-use parts, assemblies, customer-facing prototypes.

Material compatibility

FDM and resin; exact cleanup method depends on material and geometry

FDM + Resin

Sanded

Presentation

Typical look: Reduced layer/support texture

Relative cost $$

Lead time Moderate

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Why choose it?

Improves feel and appearance and prepares surfaces for primer, paint, coating, or bonding.

Things to consider

Can soften sharp edges or alter dimensions if overdone. Tight-tolerance surfaces require special care.

Best for

Display parts, housings, painted parts, bonding surfaces.

Material compatibility

Most rigid FDM plastics and cured rigid resins; less suitable for very soft elastomers

FDM + Resin

Polished

Presentation

Typical look: Smooth / glossy surface

Relative cost $$$

Lead time Longer

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Why choose it?

Produces a refined surface on materials that can be progressively sanded and polished.

Things to consider

Labor intensive. Complex recesses may not polish evenly. Not every polymer or resin responds the same way.

Best for

Presentation models, clear parts, decorative parts, premium prototypes.

Material compatibility

Material dependent; especially useful on selected clear resins, PMMA-like materials, and polishable rigid plastics

FDM

Filler Primer

Presentation

Typical look: Uniform surface ready for paint

Relative cost $$

Lead time Moderate

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Why choose it?

Helps fill fine FDM layer texture and small sanding marks before final paint.

Things to consider

Adds thickness and requires sanding between coats. Mask critical dimensions, threads, and mating surfaces.

Best for

Cosmetic housings, props, presentation prototypes, painted end-use parts.

Material compatibility

Common on PLA, PETG, ABS, ASA and similar rigid materials after correct prep

FDM + Resin

Painted

Presentation

Typical look: Custom color / branded appearance

Relative cost $$$

Lead time Longer

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Why choose it?

Provides colors or visual finishes that are not practical to achieve directly from the print material.

Things to consider

Requires material-appropriate prep and primer. Paint can chip on flexible parts or moving contact surfaces.

Best for

Display models, branded prototypes, housings, consumer-facing parts.

Material compatibility

Most rigid FDM and resin parts with proper surface prep; flexible parts require flexible coating systems

FDM + Resin

Clear Coat

Presentation

Typical look: Matte, satin, or gloss protective topcoat

Relative cost $$

Lead time Moderate

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Why choose it?

Protects paint and can improve appearance, cleanability, and UV resistance when the correct coating is selected.

Things to consider

A coating does not automatically make a part chemical-proof, food-safe, or outdoor-rated. Compatibility must be checked.

Best for

Painted models, presentation parts, decorative end-use components.

Material compatibility

Most prepared rigid prints; coating chemistry must match substrate and service environment

FDM + Resin

Epoxy / Protective Coating

Custom

Typical look: Thicker sealed surface

Relative cost $$$

Lead time Longer

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Why choose it?

Can fill surface texture, add a sealed finish, and improve wear or moisture resistance for selected applications.

Things to consider

Adds measurable thickness and weight and can affect fit, threads, small details, heat behavior, and flexibility.

Best for

Props, sealed housings, display parts, selected functional surfaces.

Material compatibility

Many rigid plastics and resins after proper prep; adhesion to PP, PE, POM and similar low-energy plastics is difficult

FDM

Vapor Smoothed

Presentation

Typical look: Reduced layer lines / glossy shell

Relative cost $$$

Lead time Longer

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Why choose it?

Chemical vapor can soften the outer surface of compatible thermoplastics and blend visible layer lines.

Things to consider

Only suitable for compatible materials and controlled processes. Can round edges, alter dimensions, and reduce fine detail.

Best for

Cosmetic ABS/ASA parts and select solvent-compatible polymers.

Material compatibility

Commonly associated with ABS/ASA using compatible solvent systems; not a universal option for PLA, PETG, TPU, nylon, or composites

FDM

PVB Smoothing

Presentation

Typical look: Very smooth decorative finish

Relative cost $$

Lead time Moderate

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Why choose it?

Certain PVB filaments are specifically designed for alcohol-assisted smoothing.

Things to consider

Material-specific process. Dimensional edges and fine details can soften.

Best for

Decorative models, presentation pieces, smooth visual prototypes.

Material compatibility

Compatible PVB formulations only

Resin

Resin Clear-Finish Treatment

Presentation

Typical look: Higher transparency / glossy clarity

Relative cost $$$

Lead time Longer

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Why choose it?

Wet sanding, polishing, and/or a compatible clear coating can greatly improve the appearance of clear resin.

Things to consider

As-printed clear resin is normally translucent rather than optically transparent. True optical performance requires specialized validation.

Best for

Transparent covers, visual fluid models, light guides, presentation parts.

Material compatibility

Clear / high-clarity resins designed for post-finished transparency

Resin

UV-Protective Coating

Custom

Typical look: Clear protective surface

Relative cost $$

Lead time Moderate

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Why choose it?

Can help reduce surface weathering or yellowing for selected resin parts when a compatible UV-resistant coating is used.

Things to consider

Does not make every resin suitable for indefinite outdoor use. Base resin performance still matters.

Best for

Display parts, clear parts, occasionally exposed resin components.

Material compatibility

Selected fully cured resins after compatibility testing

FDM + Resin

Custom Finish

Custom

Typical look: Project-specific

Relative cost Quoted

Lead time Quoted

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Why choose it?

For projects needing a specific texture, appearance, coating, masking pattern, or multi-step finish.

Things to consider

Requires project review. Geometry, material, tolerance, intended use, and coating chemistry determine feasibility.

Best for

Special projects, restorations, branded components, assemblies, presentation pieces.

Material compatibility

Determined during project review

Before choosing

Finishing can change the part

Dimensions

Sanding removes material while primer, paint, and coatings add thickness. Critical fits, bearing surfaces, threads, and mating features may need to be masked or compensated.

Appearance

Color, gloss, transparency, and texture depend on both the base material and the finishing process. A reference photo is helpful for custom cosmetic work.

Function

Coatings and smoothing can affect friction, flexibility, chemical resistance, electrical behavior, and fatigue. Functional surfaces should be identified before finishing.