How to Mirror-Polish

Lacquer has no single "correct" answer. What follows is one reference workflow — adjust it to fit your own habits.

Mirror-polishing is the final step that turns the lacquer surface into a mirror. It isn't hard; it just takes patience and cleanliness.

 

1. When to Mirror-Polish

Mirror-polishing follows wipe-on finishing. They are a pair, done in alternating cycles and repeated 3 times or more:

fine grinding → wipe-on finishing → cure → mirror-polish

   → (wipe-on finishing → cure → mirror-polish) → repeat at least 3 times

• Keep going until you're happy. More cycles = more gloss.

• The lacquer must be fully cured and hard before you start. A freshly dried film is soft and will fail under the pad.

• How to judge: wait several more days. A film that has sat for days feels noticeably harder than one that just dried.

 

2. What to Prepare

Materials

• Mirror-polish material — pick ONE of the options below; they are interchangeable. You do NOT need them all:

• Mirror-polish powder (simplest, cheapest, and the one most people actually use — see Section 3)

• Mirror-polish paste (ready-made, easy)

• Mirror-polish wax

• Mirror-polish liquid (finest)

  Tip: choose whichever is easiest for you to get — one is enough to do the whole job.

  Tip: want better results? Buy one material in two grades (one coarser + one finest), and that's all you need.

• Cooking oil (peanut, rapeseed, or soybean — any works)

• Dish soap or soapy water (to wash the oil off afterward)

• Wipe-on lacquer: Wipe-Build Semi-Clear Urushi

Tools

• Cotton cloth (lint-free)

• Microfiber cloth (thick; for mirror-polish liquid and paste — cotton soaks them up too fast)

• Soft brush (to clean residue out of crevices)

• Small lidded container (to keep the powder/paste clean)

Environment

• Keep the room as dust-free as you can. Dust is the lacquer surface's worst enemy.

Safety (read this)

• Urushi causes skin allergies. On first contact, wear gloves and long sleeves — do not let lacquer touch your skin.

• Mirror-polish paste can irritate skin; avoid bare-hand contact and apply it with a cloth.

 

3. Which Mirror-Polish Powder?

First, what is that white powder?

"Mirror-polish powder" is simply an extremely fine white (or light-grey) powder — essentially a very fine abrasive. Its job is to polish the lacquer surface until it glows. The white polishing powder you may already own is almost certainly this.

Which powders can you use? (pick one; finer is better)

Can use	Notes / where to get
Titanium White (titanium dioxide)	Best and easiest white substitute. Any art-supply store.
Fine brick powder	The classic Chinese choice. Crushed brick/tile, sifted very fine (or buy it ready-made as "polishing powder").
Flour / starch	Straight from your kitchen — see below.
Pearl powder	An ancient material; extremely fine and bright, just expensive.
Tooth powder	Used traditionally; available at drugstores.
Whetstone powder	Japanese method: powder from a sharpening stone.
Polishing / abrasive powder	Sold specifically for lacquer work at lacquer suppliers.

 

Which household flours work?

Not all flours are equally fine — the finer the better. By fineness:

• Finest, best: cornstarch, wheat starch, glutinous rice flour

• Also fine: cake flour

• Coarser (works but ordinary): all-purpose flour, bread flour

• Other starches OK too: potato starch, sweet potato starch, rice flour

Top three (finest, best results): cornstarch, wheat starch, or glutinous rice flour. All are smooth enough once mixed with oil. If you can get a starch, prefer it over regular flour — it is finer.

Still can't find any? Any extremely fine white polishing powder can work — for example cerium oxide (used for glass polishing) or whiting (calcium carbonate).

One hard rule: it must be extremely fine. Coarse particles will scratch the surface immediately. If unsure, sift it again.

 

4. Core Principle: Remember One Line

Start coarse, finish fine.

Whichever material you chose above, always work from coarse to fine:

• Only one material → just use it, going over the surface several times, each pass lighter than the last.

• Two grades → start with the coarser one (around 15000 grit) to remove scratches, then switch to the finest (around 30000 grit) to bring up the gloss.

• Different types can be staged too: coarse (wax / water-based paste) → medium (oil-based paste) → fine (liquid).

One hard rule: don't overwork a coarse material — it will wear through the lacquer film.

 

5. Steps

Step 1 · Wipe-on finishing (before mirror-polishing)

1. Filter the wipe-on lacquer (Wipe-Build Semi-Clear Urushi) to remove any grit.

2. Brush or wipe a thin, even coat over the whole surface.

3. Wait a few minutes for it to seep into fine scratches, then wipe the lacquer off with a cloth — until almost none is visible, leaving only a thin "mist".

4. Cure it in the curing box for 1 day (judge: dry, and lightly sandable).

Step 2 · Mirror-polishing

5. Take a small piece of cotton cloth, load it with your chosen material (for powder, mix with a little cooking oil to form a paste), and rub the surface in circular motions.

• Go round and round; cover every spot, leave nothing out.

6. Stop the moment the surface feels slightly warm.

• This is the most important rule. Warmth means you are rubbing too hard. Let it cool back to room temperature before continuing.

7. Do one area, move on to the next, until the whole surface is done.

8. Wash the oil/paste off immediately:

• Oil-mixed powder or water-based paste → wipe with a cloth dampened with water (wring it out).

• Oil-based paste / wax → wipe with a cloth dampened with soapy water or dish soap.

• Judge: no slick feel, and no more powder/paste coming off on the cloth.

Step 3 · Final pass (optional, but recommended)

9. For the last pass: dip your fingertip in the finest powder (or the finest material you have), use no oil, and lightly polish the surface directly.

• Benefit: without oil you can feel much better where you have missed a spot.

10. Wipe off the powder with a dry cloth. Done.

 

6. What "Good Enough" Looks Like

• During: surface slightly warm → stop.

• After: a mirror — clearly reflective, with a light that seems to come from within.

• Not glossy enough? It is not that you polished badly — you have not done enough cycles. Go through "wipe-on finishing → cure → mirror-polish" a few more times.

 

7. Common Mistakes (one-line fixes)

• Thinking you must use powder, paste, wax AND liquid → No. Pick one.

• Using coarse powder → it scratches. It must be extremely fine.

• Polishing before the lacquer is fully cured → fine cracks and shrinkage. Wait several more days.

• Rubbing too hard or too long → overheating. Stop when it is warm.

• Dust on the surface or cloth → scratches you cannot remove. Clean first.

• Not switching away from a coarse material → it wears through the film. Go coarse → fine.

• Not washing off the oil → it affects the next step. Wash every time.

• Do not touch mirror-polish wax with bare hands, and do not use it for the final pass (especially on colored lacquer).

 

8. Quick Numbers (reference values)

Item	Reference value
Cure after wipe-on finishing	at least 1 day (longer is better, until the film is hard)
Powder + cooking oil	about 1:1 by volume (to a paste)
Number of cycles	"wipe-on → cure → mirror-polish" at least 3 times
Grit progression (if using multiple)	about 15000 grit → 30000 grit (coarse to fine)
Surface while polishing	stop when slightly warm; let it cool to room temperature, then continue
Wood-grain wiped lacquer (for wooden items)	20+ wipe-on passes gives the best result