# Shellac under spar varnish



## Bender (Aug 10, 2008)

So I might have put my foot in my mouth, but I'm not convinced I'm wrong.

Over on CT someone asked about stripping a mahogany bar down and refinishing it.
Someone suggested putting down 2 coats of shellac and then a few coats of spar varnish. I said no to the shellac under spar. I didn't think they were compatible? Am I wrong?


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## DeanV (Apr 18, 2007)

If it is a dewaxed shellac, I think it would be fine. Otherwise, there may be problems. I could be wrong, but that is my understanding.


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## Bender (Aug 10, 2008)

I don't know Dean, I can't put my finger on it but it seems wrong.
(and I don't want to admit I'm wrong)


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## DeanV (Apr 18, 2007)

I would be worried about flexibility of shellac for exterior application though.


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## Private_Estate (Feb 13, 2009)

DeanV said:


> If it is a dewaxed shellac, I think it would be fine. Otherwise, there may be problems. I could be wrong, but that is my understanding.


 
100% correct. 

When applying a spar varnish over a conventional shellac it's not uncommon to actually see the varnish "creep" on top of the wax based shellac.

Most shellacs have a wax content. Zinsser Seal Coat is a 100% wax free shellac formula. Makes an excellent sanding sealer under any clear top coat and can be used "inbetween" a wax based shellac and a urethane/polyurethane/varish/spar varish resulting in stable adhesion.

P.E.


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