Water-base Polyurethane

I am using water based polyurethane to refinish oak kitchen cabinets. This is the first time I have used water-based for anything. My preference has been for oil based. I decided to use the water based because of the shorter drying time. The product is brand new, purchased only days ago for this project.
But I have a problem. When I apply it, it seems to not "wet" the surface. Rather it kind of beads up much as water does on a well waxed car. I can smooth is out with additional brush strokes and/or more product but I fear that it is not adhering to the wood and is destined to fall off. I have prepared the wood with light sanding and/or scotch bright to smooth the bumps and provide tooth.
What am I doing wrong? Does the water base requre some additional preparation over old work??
Thanks, Eric
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SNIP
Eric, there will be many opinions on this, and this is my take. If I HAD to use water based over an existing finish, I would wash the surface well to remove as much grime and dead finish as possible. Then I would sand the hell out of it, then wash it again with either mineral spirits or lacquer thinner (I always use lacquer thinner).
Then a coat of 1# cut dewaxed shellac (Zinnser sanding sealer or similar). Then a scuff sand, then clean again.
Then apply the finish.
If you are confident in your application equipment and its spotlessly clean condition before application, the probable reason your finish is beading up is that the surface is contaminated. By simply smoothing out material, your worst fears will be realized. It is beading for one reason or another, but beading means no adhesion. I may be OK for a while, but not long term.
If I were in your shoes, I would take a drawer or cabinet door off and do the procedures above. Don't commit your whole set of cabinets right off.
If it works when you reapply, ask yourself if you really want to do all of that... just to use water based. I have found in my personal experience that solvent based is a lot more forgiving. The downside of course is that if you are doing this to your own house, the solvent based will keep you out of it for several hours, and maybe a couple of days with mulitple coats.
Other factors can also affect your refinishing. What was the original finish? If these are factory cabinets, they can be finished anything from a cheap lacquer that is heat set, to a pre-cat lacquer baked in an infared oven. If it is a builder/homeowner cabinet, it may be anything from varnish to polyurethane. All will respond to your efforts differently.
Also, you didn't say what kind of WB finish you are using. Skip the Home Depot/Lowes stuff. Go to a real paint store and get ML Campbell, Fuhr, Sherwyn Williams, etc. They are more pricey, but all of those extra dollars translate into that much better of a product.
Good luck!
Others will follow...
Robert
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snipped-for-privacy@aol.com wrote:

What he said! Zinnser Seal Coat is available at any good paint store, accept no substitutes.
Water based products are far more sensitive to surface contaminants than many solvent based products. Refinishing can be even more difficult, due to years of kitchen grease, Pledge, waxes, and cleaning products.
Seal Coat will seal just about anything in, forming a thin, but solid barrier coat. _Any_ finish can be used over Seal Coat, regardless of formulation. It should be in every woodworking shop.
Don't forget the personal protection. WB products are often bigger health hazards than solvent based products during application.

Oddly enough, I pay less for some "pro" brands than inferior home center products.
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wrote:

SNIP
Eric, there will be many opinions on this, and this is my take. If I HAD to use water based over an existing finish, I would wash the surface well to remove as much grime and dead finish as possible. Then I would sand the hell out of it, then wash it again with either mineral spirits or lacquer thinner (I always use lacquer thinner).
Then a coat of 1# cut dewaxed shellac (Zinnser sanding sealer or similar). Then a scuff sand, then clean again.
Then apply the finish.
If you are confident in your application equipment and its spotlessly clean condition before application, the probable reason your finish is beading up is that the surface is contaminated. By simply smoothing out material, your worst fears will be realized. It is beading for one reason or another, but beading means no adhesion. I may be OK for a while, but not long term.
If I were in your shoes, I would take a drawer or cabinet door off and do the procedures above. Don't commit your whole set of cabinets right off.
I agree but you really need to find out what the contamination is. I suspect two things at this point.
1) How long have the cabinets been sitting there before you started to refinish? If it has been awhile, it could be a build up of grease. If so, a natural degreaser (not the heavy industrial types) will want to be applied before sanding. Otherwise all you will do is sand the grease in.
2) If it hasn't been too long or you have cleaned the cabinets, I suspect an oil based finish. Read above for that.
Been there.....I have an old house that has lots of mahogny trim. The previous owner never really took care of it and let there (cobb and carve it up) children do the maintenance on it. They put on a water based stain/poly all in one product over varnish. The surfaces are rougher than the sandpaper I tried at first. I am now using a heavy duty stripper, stripping only 1-2 feet of baseboard a day on the weekend. It is the only way I can get any finish to adhere.
YMMV Allen
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Sun, Jan 6, 2008, 9:42pm (EST-3) snipped-for-privacy@aol.com (RubEric) doth query: <snip> What am I doing wrong? Does the water base requre some additional preparation over old work??
You left out a lot of details I'd say. But the first thing I would have done, is use the 1-800 number on the back of the can.
JOAT You can't always judge by appearances, the early bird may have been up all night.
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