Mechanical finishing & post-processing · finish comparison
Mirror Polishing vs Polishing
Mirror Polishing and Polishing are both mechanical finishing finishes; mirror polish resists corrosion better.
Mirror Polishing
Mechanical finishing · $$$$ · instant quote
Mirror polishing removes visible directional scratches and buffs the surface to high specular reflectance.
Polishing
Mechanical finishing · $$$ · instant quote
Mechanical polishing progressively removes surface peaks and scratches to produce a smooth glossy surface.
When to choose which
Choose Mirror polish
Choose Mirror polish when a specular No. 8-class surface is required.
- Typical Ra 0.025–0.10 µm (1–4 µin)
- Produces premium specular appearance
- Improves release on polished mold faces
Choose Polished
Choose Polished when gloss is needed without full specular appearance.
- Reduces Ra to about 0.1–0.8 µm (4–32 µin)
- Improves cleanability
- Creates a glossy cosmetic surface
What the numbers say
- Mirror polish resists corrosion better.
- Polished is the lower-cost option ($$$).
Scores side by side
Each score is 0–100 against every finish in this catalog. Corrosion is derived from salt-spray test duration and surface hardness from the finish layer's Vickers hardness where a measured figure exists; a finish that leaves the base metal's own surface is not rated for hardness. Cosmetic, lubricity and cost are FabDigit's engineering assessment. Scores and typical figures are screening data, not matched side-by-side tests or service-life rankings; ASTM B117 is a controlled salt-fog method, not a field-life prediction.
| Score | Mirror polish | Polished |
|---|---|---|
| Corrosion resistance | 10 Minimal | 8 Minimal |
| Surface hardness / wear | — — | — — |
| Cosmetic quality | 95 Excellent | 82 Very good |
| Lubricity | 25 Low | 20 Low |
| Cost | 78 $$$$ | 55 $$$ |
Key numbers
| Property | Mirror polish | Polished |
|---|---|---|
| Thickness | 0 µm | 0 µm |
| Electrical | Unchanged | Unchanged |
| Relative cost | High ($$$$) | Premium ($$$) |
| Added lead time | 3–10 working days | 2–7 working days |
| RoHS | Compliant | Compliant |
| Instant quote | Yes | Yes |
Bold marks the side that is ahead on a row where more (or less, for cost and lead time) is better. Ranges are the typical specification window; the drawing call-out fixes the class.
Which materials take each finish
| Material family | Mirror polish | Polished |
|---|---|---|
| Aluminum | With care | Yes |
| Brass | Yes | Yes |
| Copper Alloy | Yes | Yes |
| Stainless Steel | Yes | Yes |
| Steel | Yes | Yes |
| Magnesium Alloy | With care | With care |
| Polymer | Limited | With care |
| Titanium | With care | With care |
| Zinc Alloy | With care | With care |
Mirror polish vs Polished — frequently asked
What is the difference between Mirror polish and Polished?
Mirror Polishing and Polishing are both mechanical finishing finishes; mirror polish resists corrosion better. Polished is the lower-cost option ($$$).
When should I use Mirror polish instead of Polished?
Choose Mirror polish when a specular No. 8-class surface is required. Conversely: choose Polished when gloss is needed without full specular appearance.
Is Mirror polish or Polished cheaper?
Polished is the lower-cost finish ($$$ against $$$$ for Mirror polish) among the finishes FabDigit quotes. Both are priced per part with a lot minimum; the exact figure appears on the instant quote once the part is uploaded.