[Quickstep]

Does it matter whether a waterborne finish is called lacquer, or varnish, or poly?

I'm curious because I want to use a waterborne finish on musical instruments and want to make sure I can sand it out and polish without fear of witness lines.

I've tried a couple of finishes called lacquers, but either found that they had a blue cast, or I had difficulty getting good results when spraying.

Someone recommended General Finishes' Enduro Var, saying it sprayed easily and looked good (like nitro lacquer) but of course, it's called a varnish and varnish is typically prone to witness lines when sanding out.

So, here's the $64 question:

Do all waterborne finishes "burn in" to the previous coat as long as the next coat is applied within the appropriate amount of time?

Last question:

Any recommendations?

 

[Dave Paine]

I have used GF Enduro-Var water based poly on a number of projects. It is my favourite water based poly since it adds a pleasant tone to the work piece, similar to oil based finish.

The Enduro-Var coats do cross-link, which is what I think you mean by "burn in". I do not know if this happens with all water based.

I apply Enduro-Var by brush. It feathers well and does not leave much in the way of brush marks.

If you want to sand the final coat, I would let the finish cure for several days. I found out the hard way if I sand too soon the product is not hard enough, gums up the paper and I had a mess on the work piece. I had to strip down and start again.

I do light sanding between coats using wet-dry paper and a few drops of water. Just trying to take off high spots, dust nibs.

 

[Rick Mosher]

I don't normally use WB products but have tested quite a few. The only one I would use that I have tested is Target Coatings EM9000. Super clear and buffed out beautifully.

 

[Quickstep]

Thanks for the feedback. Yes, by "burn in" I did mean cross link. Mostly, whatever it does to eliminate the possibility of witness lines when sanding. I've tried a few WB finishes, most designed to be sprayed. Problem is, It's hard to regulate temp and humidity in my basement shop and the ones I've tried are finicky about temp and humidity. It doesn't help that I'm a lousy sprayer. My luthier friend who recommended endure-var said it levels better than others. In fact he's brushing the base coats and shooting the last coat. He also likes the amber tone. Sounds like just the ticket. I can't wait to try it.

 

[Fred Hargis]

According to Flexner and Jewitt, all waterborne finishes are basically the same: an acrylic resin finish. Some of the companies (me talking here) always referred to the as lacquer, and then more recently some of them started adding a small amount of urethane resins so they could put that seemingly magic word on the label. But the are still overwhelmingly an acrylic finish, regardless of what the label says. I've only used Crystalac and Target coatings products, and they are both good....but I suspect many others are just as good. My only advice would be to avoid Minwax products; I personally think of them as the harbor Freight of finishes. (Just my opinion).

 

[cabinetman]

Thanks for the feedback. Yes, by "burn in" I did mean cross link. Mostly, whatever it does to eliminate the possibility of witness lines when sanding. I've tried a few WB finishes, most designed to be sprayed. Problem is, It's hard to regulate temp and humidity in my basement shop and the ones I've tried are finicky about temp and humidity. It doesn't help that I'm a lousy sprayer. My luthier friend who recommended endure-var said it levels better than others. In fact he's brushing the base coats and shooting the last coat. He also likes the amber tone. Sounds like just the ticket. I can't wait to try it.

Manufacturers can call their product what they want in order to sell it. If calling a waterbase product lacquer, previous lacquer users are likely to buy it. There is a simple chemical revelation with media. Check to see what is recommended for clean up or reducing. If the chemical is lacquer thinner, it's a lacquer product. If it's water, it's a waterbase polyurethane. Check the MSDS of the waterbase polyurethanes, and they are all pretty much the same.

If you are finishing and "leveling out", you may be applying too much. If you are sanding, and get witness lines, you may be sanding too much. If you get a grey or hazy coating you applied too much. If you let it puddle or pool, you applied too much. If you want some "burn in", add a small percentage of lacquer thinner to the mix. For the products that say no thinning needed, those will work better with about 5% thinning with water. That's about a ½" of water in the bottom of a 1qt cup.

WB polyurethane isn't affected by high humidity, or lower than normal temperatures, as it will dry and might take a bit longer. It doesn't blush. When experimenting with it, learn to spray. Get your paths wet, but not enough to run. Use a lot of light and get a glare on your work, so you can see what you're doing. Spray thin coats.

.

 

[Quickstep]

Dave,

Thanks for the insight. Can you let me know what kind of brush you're using and any brushing tips? I had hoped to be able to brush on my first coats and shoot the last coat, but I'm getting lots of brush marks.

I have used GF Enduro-Var water based poly on a number of projects. It is my favourite water based poly since it adds a pleasant tone to the work piece, similar to oil based finish.

The Enduro-Var coats do cross-link, which is what I think you mean by "burn in". I do not know if this happens with all water based.

I apply Enduro-Var by brush. It feathers well and does not leave much in the way of brush marks.

If you want to sand the final coat, I would let the finish cure for several days. I found out the hard way if I sand too soon the product is not hard enough, gums up the paper and I had a mess on the work piece. I had to strip down and start again.

I do light sanding between coats using wet-dry paper and a few drops of water. Just trying to take off high spots, dust nibs.

 

[Toller]

My only advice would be to avoid Minwax products; I personally think of them as the harbor Freight of finishes. (Just my opinion).

12 years ago I bought some Minwax wb for a cub scout project. A couple weeks ago I decided it was tme to get rid of it, but how?
I used it up varnishing my basement stairs, which are raw osb. Worked great after 12 years. Says a lot for HF