Shellac and wax

[marlin adams]

I was just wondering why would a person use shellac with wax in it? The reason I ask since its been over 30 yrs ago I work for a antique store where I was a apprentice to a guy where we repairedand refinish antiques and build antique replicaes and he always used shellac with no wax among other finishes and the finish piece always come out beautiful and when refinishing a piece for a custome they always prefer it over other finishes more than any other.

[Jim Morgan]

Shellac is an organic material (made from secretions of the lac beetle) that naturally contains waxy compounds. Removing these requires additional refining and raises the price of the finished product. Shellac will stick to itself whether it is dewaxed or not, so if shellac is the sole finish material, the extra expense may not be justified. On the other hand, the wax does inhibit adhesion of oil and water based finishes, so shellac used as a sealer or barrier coat should be dewaxed.

[Jim Becker]

James is correct...shellac in its native form contains natural waxes. De-waxed is something that is more popular at this point because it's often used for purposes beyond "the finish", such as a barrier coat between dissimilar finishing products to insure proper adhesion. The natural waxes can interfere with that.

[John TenEyck]

I use waxy amber shellac because that's what Zinsser puts in the can, and I'm not going to the expense and trouble of making my own from dewaxed flakes. I've never had any problems with it and it looks great. I typically spray a coat of Sealcoat over it if I want to apply a WB topcoat over it. Never had a problem in 10 years.

John

[Ted Phillips]

I don't typically use dewaxed shellac because the wax adds a degree of flexibility to the finish that I like. Pure dewaxed shellac resin can cure very hard and can crack or craze if the wood underneath it moves (only a problem if built up into a thick layer). That's why you see instrument makers using buttonlac or other less-refined types of shellac - they want the finish to be a little flexible in the event of wood movement or dings in the surface of the piece during normal wear and tear.