Reply To: Shellac solvent

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I’ve spend a lot of time dissolving my own shellac flakes.

My preference is to use 190 proof drinkable alcohol. I think this solution of shellac dries the most quickly but they all dry fairly fast so this is relaly a minor point. Mostly drive by my thoughts if I could drink it, breathing some of it is likely better than breathing the alternatives. Can’t legally purchase it in California. As such, when I am in in Oregon, Washington State, or Nevada, I buy a few bottles ($20-$30 per bottle depending on the states sin tax). I use at most two bottles a year. If I couldn’t get it that way, I would try the 190 proof alcohol that they sell at around $100 a gallon on Amazon for making your own plant extracts. Spendy but would likely last me two years. Speaking of Amazon, I would NOT order the 200 proof ethanol for shellac. Due to the azeotrope ethanol forms with water, you can’t easily get past 190 proof from “simple” distillation. A way to go from 190 to 200 proof (I am a chemist so I speak from experience) is to add some benzene to the 190 proof ethanol and then distill. It removes the water. For chemistry, water often competes with ethanol in organic reactions. Trace benzene does not. However, benzene is a carcinogen and I wouldn’t want to breath it. Since I don’t know if the 200 proof ethanol on amazon contains trace benzene in it, I simply would stay away from it. There are other ways to remove the last little bits of water from 190 proof ethanol as well.

I have used 90 or 95% isopropanol and dissolved up 1.5 lb cut shellac flakes. It works. I ended up purchasing a bunch of this isopropanol in Jan 2020 just as I was hearing about the upcomming pandemic as a means to disinfect. Didn’t use much of for disinfecting so repurposing it. Mostly use it to clean shellac brush. Reasonably inexpensive.

Mohawak/Bektol make something I think called “Shellac Reducer” that I can get in CA at Woodcraft that is ethanol cut with isopropanol and n-butanol so it’s not drinkable. It works well and you can get many coats on in a day. It’s my second choice if I can’t get 190 proof drinkable ethanol. The only thing I don’t like and this is a very minor point, the n-butanol has a much higher boiling point relative to ethanol or isopropanol and if I want it to be really dry to denib I wait overnight. I can still apply coats every 30 minutes.

I no longer will use hardware store denature alcohol. I just don’t want to breath in methanol vapors. Plenty of folks are ok with this but we all have to draw our line somewhere. If I were to use denatured alcohol, I would probably do so outside.

  • This reply was modified 1 week, 1 day ago by joeleonetti.