Short answer: Polish fine, hazy scratches out of acrylic with a plastic scratch remover such as Novus No. 2 on a soft cloth. For scratches that catch a fingernail, wet sand with 400-grit wet-or-dry paper (Acrylite's starting point), step up through finer grits to 2000 or higher, then buff back to clear with a plastic polish or a muslin wheel and compound. Coated sheet (mirror backs, abrasion-resistant, scratch-resistant) can't be sanded, and deep gouges are often better replaced.

Key facts

  • Fine scratches: plastic scratch remover on a soft flannel or microfiber pad, by hand (Acrylite, Optix).
  • Deeper scratches: wet sand starting at 400 grit with plenty of water, then buff with a clean muslin wheel and polishing compound (Acrylite).
  • Novus order: No. 3 Heavy Scratch Remover, then No. 2 Fine Scratch Remover, then No. 1 Clean & Shine. Novus says No. 2 and No. 3 aren't for coated plastics.
  • Coated sheet: Plaskolite says buffing a scratch-resistant coating thins it further, and a removed coating can't be repaired.
  • Heat: acrylic softens around 195 to 220 °F. Keep power buffers moving.

First, how deep is the scratch?

Run a fingernail across the scratch at a right angle.

  • You can't feel it: it's a surface scuff or hairline swirl. Polish alone will fix it.
  • Your nail catches slightly: light-to-medium scratch. Try a heavy scratch remover (Novus No. 3) first; if that doesn't do it, sand from about 800 to 1000 grit.
  • Your nail drops in and clicks: deep scratch or gouge. Start at 400 grit, and decide first whether it's worth it (see below). Plaskolite's position is that deep gouges from keys, screwdrivers, and knives can't be repaired; in practice they can sometimes be sanded out on thick sheet, at the cost of a slight dip.

Also check what kind of sheet you have. Mirror acrylic has a thin metallic coating on the back, and abrasion-resistant (AR) or scratch-resistant (such as Optix SR) acrylic has a hard coating on the face. Sanding or buffing a coated face removes the coating. On mirror acrylic, scratches on the front (the plastic side) polish like regular acrylic, but scratches through the back coating can't be repaired. How mirror acrylic is made.

How to remove fine scratches with polish

  1. Wash the area with mild soap and water and dry it. Grit left on the surface makes new scratches. (How to clean acrylic safely.)
  2. Apply a plastic scratch remover to a soft flannel, microfiber, or foam pad. Common choices: Novus No. 2 Fine Scratch Remover, Meguiar's Mirror Glaze M17 Clear Plastic Cleaner followed by M10 Clear Plastic Polish, or Meguiar's PlastX for uncoated clear plastic.
  3. Rub with firm, even pressure in small overlapping circles or straight strokes, working an area a few times larger than the scratch so you don't leave a visible dip.
  4. Wipe off, inspect under a bright light at a low angle, and repeat. Finish with a non-abrasive cleaner such as Novus No. 1.

Novus describes No. 2 as removing fine scratches, haze, and abrasion rather than filling them. For heavier damage, use No. 3 until only fine scratches remain, wipe it all off, then finish with No. 2 and No. 1. Test in a hidden spot first.

Car cleaner polish also works on hairline scratches; Plaskolite notes its mild abrasive takes off a little and its wax fills what's left, so they're less visible. Toothpaste works in a pinch on tiny scuffs because it's a mild abrasive, but it's inconsistent and messy.

How to remove deeper scratches by wet sanding

Sanding sounds alarming on a clear panel, but it's how acrylic is restored. You remove a thin layer of plastic around the scratch until its bottom is gone, then replace coarse scratches with finer ones until they're too small to see.

  1. Use wet-or-dry sandpaper and plenty of water with a drop of soap, rinsing the paper often. Water keeps the plastic cool and carries away swarf. Dry sanding heats acrylic and can gum or smear it.
  2. Back the paper with a flat block (a rubber sanding block or a piece of wood) so you don't dish the surface.
  3. Start at the finest grit that removes the scratch: 400 for deep ones (Acrylite's starting grit), 600 to 800 for medium. Sand until the scratch is gone and the area is evenly frosted.
  4. Step up through the grits: for example 400, 600, 800, 1000, 1500, 2000, and 3000 if you have it. At each step, sand until every mark from the previous grit is gone. Turning 90 degrees between grits makes old marks easy to see.
  5. Feather the edges. Work a wider area with each finer grit so the repair blends in.
  6. Polish. After 2000 grit or finer, the area looks evenly hazy. Novus No. 2 by hand, or a muslin buffing wheel on a drill with plastic compound, brings it back to clear. Acrylite suggests a final pass on a clean cotton or flannel wheel with no compound for the highest gloss.

Caution: Keep a power buffer moving and use light pressure. Acrylic softens around 195 to 220 °F, and a buffer held in one spot can melt a dip or leave a wavy distortion that's harder to fix than the original scratch.

Will the repair be invisible?

On a small area with a full grit progression, usually yes to the eye. On a large window or a panel viewed at an angle, a sanded patch can show as a slight lens-like distortion, because the sheet is now a few thousandths of an inch thinner there. Spreading the work over a wider area reduces it. For optical uses, such as a camera window or a display case front, a replacement panel is often the better answer.

When should you replace the panel instead?

  • The scratch is deep enough that sanding would leave a visible dip, roughly anything more than a few thousandths of an inch deep on thin sheet.
  • The panel is covered in scratches (common on tabletops and sneeze guards). Restoring a whole surface by hand is a lot of work.
  • The sheet is coated: mirror backs, AR and scratch-resistant coatings, and non-glare textured surfaces can't be sanded and restored.
  • The panel also has crazing, a network of fine cracks. That's damage inside the plastic, and polishing won't remove it. See what crazing is.

We can cut a replacement to your exact size and finish the edges to match, flame-polished or machined. Enter your dimensions in the instant quote, or upload a drawing if it has holes or curves. If your edges are the scratched part, see how to polish acrylic edges.

How do you keep acrylic from getting scratched again?

Most scratches come from wiping dust off dry, from paper towels, and from sliding things across the surface. Rinse before wiping, use microfiber, and put felt pads under anything that sits on an acrylic shelf or table cover. Acrylic is harder than most plastics but much softer than glass; see how scratch-resistant acrylic really is.

Questions

Can I use a heat gun or torch to remove scratches?

Not on the face of a sheet. Flame polishing works on cut edges, but on a flat face it tends to cause distortion, bubbles, or stress that can craze later. Sand and polish instead.

Does toothpaste remove scratches from acrylic?

On very light scuffs, plain white (non-gel) toothpaste can help because it's a mild abrasive. Results are uneven, and a plastic scratch remover like Novus No. 2 does the same job more predictably.

Which Novus number do I use first?

Start with the gentlest one that works. Novus No. 2 for fine scratches and haze; No. 3 for heavy scratches, followed by No. 2. Finish with No. 1, which is a non-abrasive cleaner, not a scratch remover.

Does this work on polycarbonate too?

Partly. Polycarbonate is softer and gums up when sanded, so it's much harder to restore to clear. Fine scuffs polish out, but deep scratches are usually permanent. Many polycarbonate sheets also have a hard coat that polishing would remove.

Are there scratch fillers for acrylic?

Wax-containing polishes leave a thin film that hides very fine scratches temporarily, and it washes away over time. Removing the scratch by polishing or sanding is the lasting fix.

Sources