We build all high-end custom furniture items for mostly residential applications in FL. Currently we outsource finishing, but would like to do our own. We are looking into using water-based products and would like to know if anyone has any information on their advantages and disadvantages. The idea is to avoid huge set-up costs with filtration systems, etc. and to also avoid environmental regulation problems. Is it to our advantage to try water-based finishes? Can superior results be achieved with these products?
We have tried a number of water based finishes in the last six years, and believe that we have found the hardest one on the market - Sherwin Williams Kem-Var W. It is a catalyzed conversion varnish. The VOC's are 1.02 lb. It comes in a five gallon container which we then move to one gallon milk jugs for easier use. We use Binks respirators with charcoal filters, as we have always used on all water based, and in the old days, oil based finishes. We use a Binks 2201SS cup gun with 66SD tip at about 40 psi. Before the 2001 model we used a Binks Model 18 and it worked just fine, but it was beginning to rust because it was not updated to Stainless Steel. I think that any SS gun would work so you should not have to change systems other than changing fluid needle, nozzle, and tip to SS.
We spray three coats of finish on all projects, and use W for all three coats, which simplifies the whole process. Our finish room is simply a room with an 18" fan that exhausts out side. Since the VOC's are so low and the finish is not flammable, there is no concern with harming the environment. After using oil-based products for about 19 years, it was affecting my health. Now I only feel tired after spraying a set of kitchen cabinets, and not stoned out of my mind!
Moving to water based finishes is scary. There are stories about how the water base does not hold up to abuse as well as oil base, I disagree. Once the W is set up good, and it has been applied in the correct mill thickness, lacquer thinner will not hurt it. Heat will soften water base finishes but once the surface cools off it returns to normal. With environment regulations getting tighter, water base finishes will be the only way to go unless you have a healthy bank account that will allow you to put in a spray booth that will meet those new regulations.
I recommend a hybrid system. Solvent based stains and glazes with waterborne topcoats.
There was an article at www.targetcoatings.com written by a guy using water-base to finish musical instruments. If the article is still there, you can see for yourself the stunning finish that water-base finishes can achieve once you master the proper techniques.