Maintenance
Acrylic is attacked by cleaners that are perfectly normal on glass. The damage is not on the surface, so it cannot be polished away — which makes cleaning the single highest-value thing to get right.
We replace more acrylic panels because of cleaning than because of impact, and the mechanism is always the same. A cleaner that is fine on glass contains a solvent that acrylic cannot tolerate, the panel is wiped over, and within days a network of fine cracks appears. It looks like fog and it is permanent.
Use the least aggressive thing that removes the dirt, and never let a solvent sit on the surface. In practice that means water with a little mild detergent for almost everything, a soft cloth, and a rinse. Everything else on this page is a variation on that.
| Agent | Verdict | Notes |
|---|---|---|
| Water, mild detergent | Safe | The default. A drop of washing-up liquid in a litre of water. |
| Isopropyl alcohol (70%) | Grey — occasional | Short contact is tolerated. Daily use crazes stressed areas near holes and bends. |
| Ethanol | Grey — occasional | Similar to IPA. Do not use on a hard-coated face without checking the coating. |
| Ammonia-based glass cleaner | Never | The most common cause of crazing in retail and hospitality. Reads as "glass cleaner" on the label. |
| Acetone, MEK, nail polish remover | Never | Immediate, severe crazing and surface melting. |
| Toluene, xylene, paint thinner | Never | Attacks the polymer. |
| Brake and carburettor cleaner | Never | Common in workshops; instantly destroys a guard panel. |
| Quaternary ammonium sanitiser | Grey — dilute, occasional | Used hourly in food service, it will dull a polished edge over months. |
| Chlorinated bleach solution | Grey — short, dilute | Overnight soaking crazes. Rinse thoroughly. |
| Commercial dishwasher (60–70 °C + alkaline) | Never for daily use | Dulls the edge and crazes stressed areas within a few hundred cycles. |
| Cerium oxide polishing compound | Safe | For removing scratches, not for routine cleaning. |
If a cleaning contractor or a facilities team is responsible for the panel, the cleaning product name belongs in the handover document. We have seen entire shopfitting programmes go cloudy because a subcontract cleaner used an ammonia product on a Saturday night.
Residue from protective film is best removed before it cures. Peel the film slowly at a shallow angle in a warm room, pulling it back over itself. If a residue remains, a little isopropyl alcohol on a soft cloth will lift it. Do not use a scraper, and do not use a solvent-based adhesive remover — those are exactly the products that craze the panel.
The other cause of stubborn residue is leaving the film on a part stored in the sun or in a hot workshop. The adhesive migrates into the surface and can only be polished out, which means the part is no longer flat where it was polished.
A scratch that does not catch a fingernail is in the surface layer and can be removed. A scratch you can feel is a gouge, and polishing it out leaves a visible lens.
Crazing is a network of fine cracks that penetrate into the material, usually starting at a hole, an edge or a bend. It scatters light, so it reads as a white haze, and it cannot be polished out because the damage is below the surface. A crazed part has also lost strength at the crazed area.
There is only one answer: replace the part, and change what caused it. If the cause was a cleaner, change the cleaner. If the cause was a solvent that splashed, protect the panel. If the cause was stress at a fixing, change the fixing detail — otherwise the replacement will craze in the same place.
A cleaning instruction that says "clean with a suitable cleaner" will not be followed, because the person cleaning does not know what suitable means. Write the product name, or write the prohibition:
Clean with water and mild detergent only. Do not use ammonia-based glass cleaner, alcohol wipes, acetone or abrasive pads.Wipe with a soft cloth; do not dry-wipe; blot dry after rinsing.For disinfection, use [product] at [dilution]; rinse and dry after contact.Three lines on a maintenance card prevent most of the replacements we are asked to quote. It is the cheapest quality intervention available on an acrylic installation.
Dilute white vinegar is generally tolerated for occasional use and is better than an ammonia cleaner, but it is acidic and repeated use will dull a polished surface. Water and mild detergent remains the safer default.
If it happened in one pass, the cleaner contained a solvent — most likely ammonia or an alcohol in a high concentration — and the panel crazed. If it happened gradually, it is surface abrasion from a cloth or paper towel. The first cannot be fixed; the second can be polished.
No. Even at low pressure, the jet drives particles across the surface and can chip edges. If a pressure washer is unavoidable on a large installation, use the widest nozzle at the lowest pressure, keep the lance well back, and never direct it at an edge or a fixing.
Use a product compatible with PMMA at the specified dilution, wipe rather than soak, and rinse. Standard 70% IPA wipes are acceptable occasionally but daily use will craze stressed areas; a hard-coated sheet is the better specification where daily disinfection is required.
No. A hard coat improves scratch and chemical resistance significantly but does not make PMMA suitable for a 70 °C alkaline wash cycle. For dishwashing, the material is polycarbonate or melamine.
If the part will be wiped with a sanitiser or a solvent, name the product and we will specify a sheet and a finish that survives it.