Work out which material you have first, because the standard blue glass cleaner under your sink will permanently damage an acrylic case. Ammonia-based cleaners attack acrylic and cause crazing - a network of fine surface cracks that cannot be polished out. On glass the same product is fine. Same cloth, same motion, completely different outcome.
This guide is about cleaning the case. If the models inside are dusty, that is a different job with different rules - see cleaning dust off model cars without damaging them.
Which material do you have?
Most collectors are never told, and the two look similar behind a lit display. Three quick checks:
- Tap it. Glass rings; acrylic gives a duller, plastic knock.
- Temperature. Glass feels cold to the touch. Acrylic sits close to room temperature.
- Edges and weight. Acrylic panels are noticeably lighter, and the cut edges often look slightly milky or rounded rather than sharp.
If you are unsure, treat it as acrylic. The acrylic method is safe on glass; the reverse is not.
Acrylic
Never use
- Ammonia-based glass cleaner. The blue stuff. This is the single most common way collectors ruin a case, and the damage is permanent - crazing cannot be polished out, only lived with.
- Solvents: acetone, alcohol-heavy sprays, white spirit, nail polish remover.
- Paper towel or kitchen roll. Wood fibre is harder than acrylic. It scratches, every time, in a fine haze you notice about a month later.
- Anything abrasive: scouring pads, dish sponges with a rough side, dry dusters that have been on other surfaces.
Use
- Flood first, wipe second. Mist the surface generously with lukewarm water containing a drop of mild dish soap. The liquid lifts grit off the surface so your cloth is not dragging it.
- Clean microfibre, light pressure, straight passes. No circles - circular scratches catch the light from every angle, straight ones only from one.
- Second dry microfibre to finish, again in straight passes.
- For stubborn marks, a dedicated plastic or acrylic cleaner. There are polishes made for acrylic that fill very fine scratches; they work on haze, not on crazing.
The order matters more than the product. Nearly all acrylic damage comes from wiping a dry, gritty surface - the cleaner is rarely the problem, the first pass is.
Glass
More forgiving. Ordinary glass cleaner is fine, or a 1:1 mix of water and white vinegar.
- Spray the cloth, not the case. Overspray runs down into the base, and in a lit case that means it runs toward the electronics.
- Microfibre still beats paper towel - not because glass scratches easily, but because paper leaves lint exactly where you can see it.
- Finish with a dry buff to avoid streaks. Streaks are almost always too much product, not too little.
The static problem
Acrylic holds an electrostatic charge, which is why an acrylic case often looks dustier on the outside than the shelf beside it. Dry-wiping makes it worse twice over: it drags grit across the face, and it recharges the surface so fresh dust arrives within hours.
A damp cloth discharges the surface as well as cleaning it. That is the real reason "damp, then dry" outperforms a dry duster here - it is not only about grit. Anti-static sprays formulated for plastics exist and work; household fabric softener solutions do not belong anywhere near a display case.
Inside the case
Two rules that apply regardless of material.
Take the contents out first. Cleaning around a model means working in a confined space with a wet cloth next to something with printed decals and small mirrors. Lift it out, clean the case, put it back.
Keep liquid away from anything electrical. Lit cases have an LED, wiring and often a sensor and a battery. Spray the cloth rather than the case, keep the cloth damp rather than wet, and let everything dry fully before switching it on. If yours is one of ours, the full specification of what is inside is on the specs page, and setup and care guidance is on the support page.
Haze, fog and marks that will not come off
| What you see | Likely cause | Can it be fixed? |
|---|---|---|
| Fine overall haze on acrylic | Dry-wiping or paper towel over time | Partly - acrylic polish reduces it |
| Network of tiny cracks | Crazing from ammonia or solvent | No. Permanent |
| Cloudy film inside the glass | Off-gassing from adhesives or plastics in a sealed case | Yes - clean and air it out |
| Streaks after cleaning | Too much product, or a dirty cloth | Yes - re-clean with less |
| Yellowing of the panel itself | UV exposure over years | No. Move it out of daylight |
That last row is worth taking seriously: the panel yellowing is the same mechanism that yellows white plastic on the models inside, and it is a placement problem rather than a cleaning one. See can you display diecast near a window.
How often
Less often than you think, and that is the point of a sealed case. A properly enclosed display needs the outside wiped when it looks like it needs it - and the inside almost never, because nothing is getting in. An open shelf needs attention constantly, which is the argument for enclosure made in how to protect diecast cars from dust.
Every cleaning cycle carries a small risk. The best-maintained case is the one that rarely needs touching.
FAQ
Can you use Windex on a display case?
On glass, yes. On acrylic, no - ammonia-based glass cleaners cause crazing, a network of fine surface cracks that is permanent and cannot be polished out. If you are not certain which material you have, treat it as acrylic.
How do you clean an acrylic display case without scratching it?
Mist it generously with lukewarm water and a drop of mild dish soap first so the grit floats free, then wipe with a clean microfibre cloth in straight passes under light pressure, and finish with a second dry microfibre. Never use paper towel - wood fibre is harder than acrylic.
Why does my acrylic case attract so much dust?
Acrylic holds an electrostatic charge that pulls airborne particles to its outer surface, and dry-wiping recharges it so the dust returns within hours. A damp cloth discharges the surface as well as cleaning it.
What causes the fine haze on an old display case?
Usually thousands of tiny scratches from dry-wiping or paper towel, rather than dirt. An acrylic polish will reduce it. If instead you see a network of tiny cracks, that is crazing from a solvent or ammonia cleaner and it is permanent.
Should I clean the inside of a sealed display case?
Rarely - if it is genuinely sealed, very little gets in. Take the contents out before you do, spray the cloth rather than the case, and keep liquid away from any LED, sensor or battery.