Pre-Cat Lacquer Basics

A first-timer gets tips on the fundamentals for success with pre-catalyzed lacquer. December 15, 2005

I am using a satin (Mohawk) dura coat pre-cat lacquer on a wall unit. It's going to be applied on mahogany plywood and hardwood with a wipe-on mahogany stain. It almost has a plum touch to it. This is my first attempt to spray. I used to paint cars way back, so I have a small clue. I just need some tips. How many coats? Does it run? Can you repair a mistake? Do you sand in between coats or not at all? Can you use furniture polish on it when completed? It seems that, from the retailer, you sand with 220-320, wipe on the stain, let dry however long that is. Then spray one super light coat, then two more regular coats. Does this sound right?

Forum Responses
(Finishing Forum)
First of all, after applying stain, you should wait 24 hours before spraying the lacquer. Yes, it will run if applied too thick. Three coats will be sufficient. You need to buff in between coats and you can fix mistakes, but it's not necessarily easy. It's easier to fix the first coat than it is the second or third. More often than not, you'll end up sanding it all down when mistakes are made on a second or third coat.

Sand your first coat with 320, easy on sharp corners. Sand your second coat with 400. Third coat will be your final.

First, you need to white sand no more than 180. I would suggest 150 before applying your stain. If you sand above 180, you will be increasing your chances for bad adhesion and you'll be wiping your stain clean. Second, apply your first coat 3 to 4 wet mils, dry as recommended by your supplier and sealer sand with 220. Blow and/or wipe the excess dust off and apply your second coat 4-6 wet mils. Let dry as needed and touch sand spots if needed with 320. Apply your final coat the same as the second. Do not use any store bought products for cleaning or polishing. If you need to clean the surface, use one from an auto supply store. As for repairing, I would suggest a thorough sanding of the entire surface and applying a thinned coat of topcoat.

From Paul Snyder, forum technical advisor:
Always ask for the technical data sheet and material safety data sheet (MSDS) when you buy new products. The tech sheet for the stain should tell you what grit to sand to and the dry time needed before applying the topcoats.

150 grit is a good general use sandpaper before applying a wiping stain. Some brands recommend 120 grit for their wiping stain. Some stains are ready to be topcoated in under an hour and some take a lot longer; check the directions or data sheet.

If you're not going to use a vinyl or sanding sealer over the stain, you may want to thin the first coat of finish by 20% or so to promote it sealing the pores. Once dry, sand very lightly to smooth, and spray the next coat. Scuff sand the 2nd coat as needed and spray the 3rd. You should be done.

A lot of pre-cat lacquers have a maximum dry film thickness. Usually, 3 regular coats will get you there, so you don't want to spray too many. If you spray too heavily, you will get sags/runs.

As a longtime user of Mohawk products, I will tell you that Dura coat is very user friendly and can easily be repaired. There is really no need for more than one seal coat and two top coats, sanding between each coat. If you are using Mohawk stains or dyes and you wait more than 20 minutes before you finish over them, you are just killing time. The 24 hour stuff is for those who still choose to use the crap from the Depot. Dura coat has very high solids and still flows out very well. You can cut it 10% to speed up drying about 15-20 minutes before sanding.

I'm spraying my second project with Dura-coat right now - I just came in from the shop to take a break. I really like the stuff. The first time I used it was also the first time I had sprayed a finish and it came out great. If you're using the Mohawk dye stain, you can begin finishing it almost immediately. I use their sealers before the first coat of lacquer (the vinyl sealer seemed to build a little better - they were out of it this time, so I'm using the regular sealer). Also, it is pretty easy to repair and I haven't had many problems with runs. Just take your time and I think you'll be happy with it, too.

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor J:
I'm working on a cherry jewelry box right now, and have found that sanding the wood all the way up to 3600 grit gives fantastic results when staining. There are no blotches at all, and the stain adheres just as well if you sanded it with 180 or something. Any higher than that though, and the wood tends to have a glossy sheen, and lacquer doesn't like to adhere to the wood.

I use a kit from micromesh to sand my final coat of lacquer to a mirror finish. Itís a kit that has 1500 grit all the way up to 12,000 grit, and it works wonders. As for the sanding, I would go ahead and knock the orange peel off with 320 grit, then spray your second coat. The solvents in the second coat of lacquer will liquefy the coat beneath it, which is why you can't put 5 or 6 coats of lacquer on. You don't have to go crazy with the sanding, just enough to get the first coat flat.