# Shellac vs polyurethane



## Joe Kobylski (Jan 24, 2009)

I am cosidering using shellac instead of poly . Is anyone familiar with this finish,


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## jerry (Nov 1, 2006)

A lot of people are familiar with shellac but what you are asking sounds like comparing apples and oranges.

Jerry


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## Just Bill (Dec 29, 2008)

I agree, shellac, done in the old way is a beautiful finish, but not very durable. If alcohol is spilled on it is dissolves, water leaves rings, etc. Poly is very durable, and finished right, as beautiful. I am rebuilding/finishing a 36 plymouth woody with marine poly. It will be much more durable than anything they would have used in '36, and looks better. I am ending up with 9-12 coats, sanded after each coat, and wet sanding after about 4-6 w/600 wet/dry. Result is a glass finish.


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## artfmv (Dec 20, 2008)

*Poly over shellac*

From what I've read, and I've been reading quite a bit on the subject, the vast majority of experts say you absolutely can't use poly over shellac unless it is de-waxed. There are also many people on the other side of the argument claiming years of finishing experience and years of doing this without adhesion problems.

I am finishing my kitchen cabinets, which are soft maple. I want a very natural look, but not just clear. Because of the blotching, I really don't even want to attempt to stain, as I have done so on some large samples, with many colors, and am just not happy with any of them. I did come up with a blend of Zinsser clear, and Zinsser Amber that gave me exactly what I am looking for in color. So, both of these have wax and even if I wanted to jump to the side of the fence that says its OK, I think to myself, why take the chance that I'll have adhesion problems and not find out until its too late.

Sorry for the long winded post, but to me, it boils down to this:

1. Can I apply my blend to get my color, then apply a coat of Zinsser de-waxed sealcoat shellac, and then poly on the top? 
2. What about varnish or lacquer as the top coat for durability?

Thanks in advance!


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## mwhafner (Jan 16, 2009)

I have mixed emotions about using a shellac finish, and then poly on top. My tests have shown mixed results. The Zinnser system works pretty well, but I haven't had much luck mixing brands.

However, you can use shellac as an initial sealer. It will prevent most blotches. Then use a good quality gel stain and poly finish. I have never had any problems with this method, especially if you aren't trying to finish too dark.


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## artfmv (Dec 20, 2008)

Thanks for the feedback. But, curious about the gel stain in this case. I have tested the shellac as a sealer and you're right, it did a great job preventing the blotching (still have minimal amounts). In experimenting I ended up with the exact color that I want. Seems like I could skip stain altogether which is why I consider going straight to poly. Since I shouldn't do that over top of the waxed stuff, I guess I'm just looking for something that will be sure to stick, or an alternative to poly that will work better over top of the shellac.


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