Mirror acrylic — also known as mirror plexiglass or PMMA mirror — is an acrylic sheet with a vacuum-deposited metallic coating on the back face that creates a mirror-like reflection. Unlike glass, it is lightweight, shatter-resistant and can be precisely cut on a CNC router. The silver variant replicates the look of a classic mirror; the gold gives spaces a warm, luxurious character. See the available shades and thicknesses of mirror acrylic in our offer.
Construction and Types of Mirror Acrylic
Mirror acrylic consists of three layers:
- PMMA substrate (2–6 mm) — base of clear or lightly tinted acrylic
- Metallic coating — thin layer of aluminium (silver) or copper-gold alloy (gold), applied by vacuum deposition
- Protective film — adhered to the coating side, removed after installation
Available finishes:
- Silver mirror acrylic — neutral, cool reflection, classic mirror look
- Gold mirror acrylic — warm, intense gold-toned reflection, premium feel
- Bronze / rose gold mirror acrylic — subtler tones, very popular in signage and interior decoration
- Single-sided vs double-sided mirror — the coating is standardly on one face (the back); double-sided is a special-order item
Mirror Acrylic vs Glass Mirror
| Feature | Mirror acrylic | Glass mirror |
|---|---|---|
| Weight (3 mm) | ~3.6 kg/m² | ~7.5 kg/m² |
| Shatter resistance | ✓ high | ✗ brittle |
| CNC cutting | ✓ straightforward | ✗ requires glass tools |
| Moisture resistance | ✓ | ✗ (silver tarnishes) |
| Price | $$ | $ |
| Reflection quality | 90–95% of glass | 100% |
| Thermal bending | ✓ possible | ✗ |
Mirror acrylic excels wherever glass is too heavy, fragile or difficult to cut into complex shapes.
CNC Machining Parameters
The key rule: the metallic coating always faces DOWN during milling — the cutter must not contact it, otherwise the reflection will be scratched along the cut line.
Milling and cutting
- Spindle speed: 18,000–22,000 rpm
- Feed rate: 2,000–3,500 mm/min (slower than standard acrylic — the coating is sensitive)
- Cut depth: max 40% of cutter diameter
- Cutter: single- or double-flute plastic-specific (sharp O-flute)
- Cooling: compressed air only — no coolant fluids that could seep under the coating
Engraving
Engraving on mirror acrylic produces a satin or matte patch against a mirrored background — highly legible and striking.
- Engraving depth: 0.2–0.5 mm (do not penetrate the metallic coating — only the PMMA layer)
- Engraving from the front face (mirror side) removes the coating and exposes clear acrylic — glass-like effect
- Engraving from the back face (PMMA side) leaves the coating intact — depth and three-dimensionality effect
Protective film
Leave the protective film on the coating side during milling — it guards against scratches from clamping pressure and chips. Remove only after installation.
Common Mistakes When Cutting Mirror Acrylic
1. Milling from the wrong side. If the cutter contacts the metallic coating, it scrapes it along the cut line — the edge looks "stripped". Always mill from the PMMA side.
2. Feed rate too high. The metallic coating chips at the edge under vibration. Slower feed = cleaner edge.
3. No protective film. Acrylic chips scratch the coating during machining. Remove the film only after cutting is complete and the work area has been cleared.
4. Vacuum clamping without a backing sheet. Mirror acrylic is often thin (2–3 mm) and can deflect on a vacuum table. Use soft gaskets or mechanical clamps for smaller details.
5. Polishing with abrasive compound. Standard acrylic polishing pastes contain abrasives that dull the metallic coating. Clean only with a soft cloth and water or a dedicated mirror cleaner.
Edges — Polishing and Finishing
Mirror acrylic edges after milling expose the cross-section of all layers — clear PMMA plus the metallic coating. For a clean finish:
- Flame polishing — removes milling marks, the edge becomes transparent
- Mechanical polishing — felt wheels with diamond paste
- Leaving a matte edge — in some designs the contrast between matte edge and mirror face creates an interesting visual effect
On gold mirror acrylic, a polished edge takes on a golden tint, amplifying the premium look.
Applications of Gold and Silver Mirror Acrylic
Advertising and signage
- 3D letters and logotypes — CNC-routed from gold mirror acrylic, bonded to reception walls and shop fronts. The reflection from the backing wall creates a halo around the letters.
- Premium signs — instead of standard white acrylic, a mirror background dramatically raises the perceived value of the sign.
- Information plaques — company names, room numbers in hotels and Grade-A office buildings.
Interior decoration
- Wall panels — gold and silver mirror acrylic mosaics, shop windows, reception counters
- Suspended ceilings — mirror tiles as a glass alternative in restaurants and hotels
- Furniture and fit-out — cabinet fronts, table inserts, display case backdrops
- Decorative elements — geometric cut-outs, plaques, frames, mirror lettering
Exhibitions and events
- Stage and trade-stand backdrops — gold mirror as a background delivers a prestigious feel at relatively low cost
- Wedding and event decoration — monograms, table numbers, seating charts, directional signs
- Photo-walls — gold mirror as a backdrop element for photography
Other
- Decorative machine guards
- Light reflectors (industrial, non-precision applications)
- Prototypes and models with a metallic finish
Installation
Gold and silver mirror acrylic is fixed in several ways:
- Acrylic adhesive — clear two-component adhesive applied from the PMMA side. Never from the coating side — adhesive destroys the metallic reflection.
- Stainless steel standoff fixings — striking "floating" mounting away from the wall, a popular method for 3D letters.
- 3M VHB double-sided tape — for flat panels on smooth surfaces.
- Screws with washers — for larger formats, covered with decorative caps.
Have a signage project, interior decoration or premium sign in mind? Learn more about our CNC milling services, browse our projects or send us a quote request — CNC workshop in Szczecin, delivery throughout Poland and the EU.