Methylated Spirits: Is it the Best Solvent for Shellac?
A woodworker friend called wanting to know where he could buy some methylated spirits. He had just read in a book that it was the best solvent to use with shellac. So I asked him if the book he was referring to was from England, to which he answered that it was.
This term has caused much confusion in the U.S. It’s often misinterpreted here as methanol (methyl alcohol) because it sounds like it. But it’s not. It’s actually British for denatured alcohol.
By breaking the term down it’s easy to understand the correct translation. First, spirits is British for ethanol (ethyl alcohol). It’s the stuff you drink when you go to a pub. The problem with using ethanol for dissolving and thinning shellac is that it’s quite expensive (think Everclear that you buy at the liquor store). So to reduce the cost, which is largely the result of taxes, some methanol is often added to make the ethanol poisonous and therefore not taxed as liquor. The ethanol spirits have been “methylated.”
There are quite a few terms used by British woodworkers and finishers that are different from those used here (some of which I mentioned in my post on French polishing terminology on Jan. 30.) Be aware of this if you are reading something from over there.
So, to answer my question in the title, I’ve not noticed a difference in the dissolving or thinning power of the alcohol used. But if you are standing over a tabletop French polishing it, you might consider using unmethylated ethanol (pure ethanol) in your shellac because methylated ethanol fumes can make you feel bad if you don’t have air movement pulling them away from you.
– Bob Flexner
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