Achieving a High-Gloss Lacquer Finish

Many coats and a thorough final buffing are the keys. March 9, 2006

Question
Does anyone know how to achieve a very high gloss with a lacquer? I have a picture of an Ikea unit wrapped in a foil, but I've seen sprayed substrates with the same level of gloss. I have a gravity fed HVLP and sprayed 90 degree lacquer on MDF, but cannot reproduce that effect. I shoot a base, sand, tack, first lacquer coat, sand (220 grit), tack, then last coat, but the piece feels bumpy with areas of flash. Am I missing a stage?

Forum Responses
(Finishing Forum)
From contributor D:
First, two coats of gloss lacquer is not enough build for a final finish. You want to achieve at least 3-4 dry mills of finish. Depending on your solids percentage by volume of your lacquer, it could take 4-6 coats to achieve that. After you have achieved your 4 mils DFT you would have to sand down the finish in stages to get a high polished gloss look, e.g., 220, 320, 600, 1200, etc. grit followed by a polishing compound and buffing it to a high gloss.


From contributor J:
Ditto to the above. It's the same process as rubbing out a car finish. Sand and buff. A car buffer works great.

From contributor A:
I would use the polishable high gloss 2k Acrylic Polyurethane (LAC367) from ICA. It is more forgiving on the total DFT than a standard lacquer.

From Paul Snyder, forum technical advisor:
Lacquer polishes to a high gloss, but it's best to let it cure for at least a couple weeks first (longer is even better). It shrinks as it cures.

Another approach is to get a good build (4+ coats) and let it dry for a couple days. Then level sand with 400 grit or higher (the higher the grit, the smoother the surface). Then spray a diluted coat of lacquer with some retarder in it to slow the dry time. This "flow coat" will give you a good gloss off the gun.

If you go the rubbing route, a catalyzed poly is a good way to go. The cure time is greatly reduced and they sand and rub out beautifully. And they're much more widely available than they use to be... most major suppliers are stocking them now. For example, both Chemcraft and ML Campbell are carrying a selection of European finishes.


From the original questioner:
Thanks to everyone for their responses. I naively assumed shooting would be enough. After I shoot 4-6 coats, how difficult is it to maintain a consistent sand/buff? Would I require one of those car buffers or would my oscillating sander suffice? Can you be more specific regarding the buffing stage including compounds required?

From contributor L:
I use ICA urethanes, wet sand to P 2000 grit and then Farcela SP rubbing/buffing/polishing compounds. Same as buffing an auto clear finish. Auto paint store is a good place to ask about buffing/polishing.

From contributor G:
35 years at this. You're not sealing well enough, for starters. Sometimes MDF seals better with shellac as base coat than lacquer sealer follow-ups, and in between coats, of course, making the last coat ultra smooth with at least 600 grit paper. Now start your gloss coats, 3 - 4 at least, and follow all those posted rub out instructions. You'll see a difference.