Wet sand and buff 2k clear to a true mirror

The part looks done when it comes out of the booth. This is the easiest place in the whole process to stop too early.

This stage picks up where Stage 04 ends: the part has sealer, base black, and its coats of 2k clear on it. Straight from the gun, that clear has some level of orange peel and probably a dust nib or two. Even a good spray session leaves texture. The job now is to cut all of it flat and bring the clear up to a true mirror.

The sequence is the same one I use on hero parts: wet sand at 1200 grit to completely flatten the surface, then 2000 and 3000 grit to bring it up to a shine, then cutting compound with a DA buffer, then polish, and finish with a swirl remover.

If you're heading for chrome, don't skip this. Chrome shows every flaw in the surface under it — the second graphite round shines best over a mirror first round.

Tools & Materials

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Before you sand

The clear has to be fully cured before you cut into it. Check the data sheet for your clear’s sand-and-polish window. A common test is the paper: cured clear cuts cleanly; soft clear gums and smears. If it gums, walk away and give it more time.

Also look at how much clear is on the part. The 1200 stage removes material, and edges carry the least of it. If the clear went on thin — one light coat instead of the full paint from Stage 04 — scuff it and lay down another coat before you start cutting. On a thin coat you’ll burn through to the base before the surface is flat.

Rinse the part, wipe it down, and keep it mounted on its work holder. You’ll be handling it constantly this stage, and the holder gives you a grip that never touches the finish.

Flatten the Clear at 1200, Wet

The 1200 pass does most of the work: it cuts the orange peel flat and takes the dust nibs with it. Everything after this only refines scratches, so any texture you leave here stays in the mirror.

1. Let the paper soak in water before sanding.
2. Sand in straight, controlled strokes with a hard block. Not circles — circles create swirls, and uneven hand pressure makes them worse. Keep the surface flooded and rinse the paper often.
3. Read the sheen. Sanded areas turn uniformly dull; anything still glossy is a low spot the paper hasn’t reached yet. It doesn’t take much pressure — you’re shaving the peaks, not digging for the valleys.
4. Go light on edges and corners. Liquid paint pulls away from edges as it levels, so they carry the least clear on the whole part and burn through first. Sand up to them, not over them.

Expect the part to look worse before it looks better. A fully sanded panel is flat and dull, and it looks like you just ruined the paint job. That’s what it’s supposed to look like — the gloss comes back in the buffing stages.

Refine at 2000 & 3000

These grits don’t change the shape of the surface; 1200 already did that. They replace big scratches with smaller ones until the compound can take over.

1. Wet-sand at 2000 until the 1200 scratches are gone. A common trick is to switch stroke direction between grits — when the old direction’s scratches disappear, that grit is done.
2. Rinse, then repeat at 3000. By the end of this pass the surface starts showing a low sheen instead of flat dull. That sheen means the scratches are fine enough to buff.

Compound, Polish & Swirl Remover

The buffing stages run coarsest to finest, same as the sandpaper did. Cutting compound is the first buffing stage — it pulls the gloss back out of the sanded haze. Polish refines that, and swirl remover takes out the fine marks the buffer itself leaves behind.

1. Run the cutting compound with the DA buffer. Set the pad flat on the surface and let the machine do the work — I’m not pushing hard, just maintaining even pressure and feathering out toward the edges instead of parking in one spot. Wipe the residue off with a microfiber cloth to check progress.
2. Follow with polish. Same technique, finer cut. The reflection sharpens noticeably at this stage.
3. Finish with swirl remover. Buff, wipe, then check the part under the inspection light. Swirl marks show up as fine spiderwebbing around the light’s reflection — keep working until the reflection is clean.

Common Mistakes

• Burning through an edge. If you cut through the clear into the base — or deeper, where you’ll see the color change between base and sealer — stop. Scuff the area, spray base again, re-clear, and come back after it cures. I’ve done it; it costs you a paint session, not the part.
• Sanding in circles. Circles create swirls. Straight strokes with a hard backer.
• Starting on soft clear. If the paper gums instead of cutting, the clear isn’t cured. More time, not more pressure.
• Clogged paper. Rinse the part and the paper often so grit doesn’t gum up the paper mid-pass.

Checkpoint: A True Mirror

The chrome goes on over whatever this surface looks like now; any texture you leave shows through the graphite.

FAQ

Why polish to a mirror if the chrome covers it anyway?

Because the chrome layer is thin — it shows the surface under it rather than hiding it. In the graphite path, the second rub shines best over a mirror first round.

Can I do this by hand, without a DA buffer?

You can. Compound and polish work by hand with foam or microfiber pads; it takes longer and it’s harder to keep the cut even across a big panel. I use the DA.

What takes out dust nibs?

The 1200 pass. Nibs are high spots, and flattening the orange peel cuts them off with the rest of the texture. It’s one of the reasons a paint job with a few nibs can still become a hero part.

I sanded through to the black. Now what?

Stop sanding that area. Scuff it, spray a coat of base over the burn-through, re-clear, and pick the polish back up once it cures. Annoying, but recoverable.

How long does the clear need to cure before sanding?

Follow the data sheet for your specific 2k clear — the windows vary by product. As a general test, if the paper gums or the surface smears instead of cutting cleanly, it needs more time.

Where you are in the series: this is an optional step in the Armor Finishing series, between Stage 04: Seal, Color & Gloss and Stage 05: Chrome — graphite & Alumaluster. You can skip it, but the deepest chrome starts from a mirror. The finishing process behind this series is built on CTProps’ tutorial. Keep the part on its work holder — it stays there through chrome.