Achieving the Desired Satin Sheen with NC Lacquer

An inexperienced finisher gets some insight into how to zero in on the satin sheen he wants by applying flatted coats over gloss coats. July 28, 2008

I have been spraying Mohawk NC lacquer and for the sake of finish clarity I build my first few coats with gloss and topcoat with 1 or 2 coats of satin. One thing I'm noticing doing it this way is that the sheen level seems more semi gloss than satin. Is this the case when building a finish this way? Because NC lacquer melts together do you get an average of the gloss and satin sheen? Should I use a flat sheen as a topcoat to end up with a satin finish?

Forum Responses
(Finishing Forum)
From contributor A:
I have always built my NC coatings in gloss for clarity followed by desired sheen top coat. These things are dependent on how many coats and mils you are laying down.

Generally speaking, the stearates/flattening pastes used in nc lacquers rise to the top as the coating dries. So while there is a melting of chemistry of the resin the resulting
"sheen" is still on top.

So, in answer to your question, are the coating sheens averaging out, and the answer is no, not exactly. However, while I try not to "should" on people, if you are not satisfied with the resulting final sheen you are getting then I suggest that you should try exactly what you are suggesting. Test a lower sheen topcoat and see if it gets you where you want to be.

From contributor M:
If I had a dollar, I'd bet that the issue isn't likely the flatting agent (usually silica) melting down into the undercoats causing a shinier sheen. Most likely what is happening is the multiple layers of lacquer (depending on how many you spray) are sealing up the wood and making a more flat, level, even, smooth surface. To our trained eyes, every sheen will look a good bit glossier over 4 or 5 sub-coats than the exact same stuff sprayed over two sub-coats.

I have noticed with NC lacquers, some folks tend to spray heavier coats to get more buildup in fewer coats, but be sure to stick to the 3-4 wet mils (use a mil gauge) and however many coats you desire with NC.

My personal favorite is three simple, light coats of satin pre-cat or conversion varnish, sanded moderately in between. On woods with somewhat-coarse grain like yellow birch, the look is stunning.

From the original questioner:
The NC lacquer is just the old, garden variety stuff. No catalysts or anything like that. I'm not a professional finisher (obviously) so my setup, and skills, are pretty rudimentary. I'm mainly spraying the mirror frames I build so wear and tear isn't as much of an issue on these pieces. I've found this finish to be reasonably quick and easy and repairable should any scratches occur.

Contributor M, you may be right about the increased coating thickness causing the appearance of extra sheen. I lay the finish on in thin coats as recommended and have found that if I build it until the pores just disappear (I'm using mostly western maple and western birch) then as it shrinks over the next week or so I get that slightly open pored, soft glow look I'm after. The cold weather here may be making this take a little longer to happen this time giving the appearance of a higher sheen than I am after.

From contributor M:
If you are a relative neophyte to spraying, I would by far advise you to consider spraying a pre-cat lacquer that has a good reputation. I am very partial to ML Campbell's Magnamax (or Magnamax Jr. which is the same thing just lower solids). Also recommend Sherwin Williams Sherwood pre-cat.

The reason I say this is that you can do in 3 coats, visually speaking, what it takes 5-6 coats of NC lacquer to do. You also do not need a sanding sealer, since the first coat of pre-cat will sand just fine. Likewise, you get a much more chemically durable coating, the pre-cat is a long-shot more durable than NC lacquer.

I know this for a fact, one of the first things I made as a cabinet maker for myself was a bookshelf, years ago. I sprayed it with 5 coats of NC lacquer. I have had books that sat there for a couple years actually stick a bit to the NC lacquer. Compare that to furniture I have that was sprayed with pre-cat, and nothing of the sort ever happens (not to mention that they are wearing much better).

Pre-cat is just quicker and more sprayer-friendly if you ask me. Oh, and the fumes are a lot more fun, so wear a mask.

From the original questioner:
Thanks for the info on the pre-cat lacquer Contributor M. It helps to hear of your experiences with both these products. I have read about the increased durability and need for fewer coats when using pre-cat lacquer or something else like conversion varnish. Maybe I'll move up to these once I perfect my spray techniques a bit.

Right now I usually just spray a few mirror frames or other small items at a time in a portable tent I set up outside my shop (somewhat rural area). Given the variability of things like temp and humidity I have stuck with regular NC lacquer. My plan is to build a designated finish room eventually with temp control, filters and fans so these other types of advanced coatings can be an option.

From contributor M:
Strangely, with humidity, you are far better off with pre-cat. You have to have close to 100% humidity, and even then, at a very high or low temp, before humidity even comes close to blushing pre-cat. And conversion varnish never blushes so far as I've seen. Depending on just how cold of a temp you are talking about, you may be fine.