What Alcohol Do You Mix Shellac With?
Mix shellac flakes with denatured alcohol, or with 190-proof grain alcohol where you can buy it. Not rubbing alcohol: the 70% product is nearly a third water, and water is what turns a shellac mix milky and a shellac finish hazy. Isopropyl at 99% will dissolve shellac if it is all you have (but is far from ideal); ethanol is the solvent the material was made for. If you want to see our deep dive on the chemistry of shellac solvents, it's in our post on The Hollow - Shellac Solvents.
Denatured alcohol
Denatured alcohol is ethanol with a denaturant added so it can be sold without liquor tax. It is the standard shellac solvent in most US shops, sold as denatured alcohol or shellac thinner. The makeup varies by brand, mostly ethanol with some methanol and other denaturants, so read the label and choose the product with the highest ethanol content you can find. The higher the ethanol, the cleaner the mix and the film.
190-proof grain alcohol
190-proof grain alcohol (Everclear is the common brand) is about 95% ethanol with nothing added. It is the cleanest solvent for shellac and the traditional one. Whether you can buy it over the counter depends on your state; some sell it freely, some don't. Where it is available, it is the first choice.
Isopropyl alcohol
It can technically dissolve shellac, but is slow and problematic - see Shellac Solvents for the chemistry behind it.
Why water is the problem
Shellac dissolves in alcohol and not in water. Water in the solvent lowers how much shellac it will carry and how cleanly it flows, and it is the cause of blush, the milky haze in a film that shows up in humid weather or over a cold surface. A dry solvent in a capped container is the first step to a clear film.
Not to use
- Rubbing alcohol (70% or 91%). A poor shellac solvent. The chemistry is covered in Shellac Solvents.
- Any alcohol that has been sitting open. Alcohol pulls moisture from the air. Keep the cap on and buy a size you'll use.
- Other thinners by assumption. Shellac is an alcohol-soluble resin; lacquer thinner and mineral spirits don't dissolve it.
State rules
Some states restrict the sale of traditional denatured alcohol; California has limited it since 2019 under its VOC rules, and a few other states and counties have rules of their own. Where denatured is hard to find, 190-proof grain alcohol is the alternative, and the paint or hardware counter will know what they're allowed to sell.
Mixing with the right alcohol
- Choose the solvent: high-ethanol denatured alcohol, or 190-proof where you can get it.
- A clean, dry jar with a tight lid. Not one that held water or a water-based product.
- Add the flakes at the cut you want. How to Mix Shellac Flakes has the ratios and the method; What Is a Cut of Shellac? explains the number.
- Cap, shake, and give it 24 to 48 hours.
- Label the jar with the grade, cut, alcohol, and date. Shelf life is in How Long Does Mixed Shellac Last?
FAQ
Can I use rubbing alcohol if it's all I have?
Better not. Isopropyl is not a great shellac solvent (see Shellac Solvents for more details). Denatured or 190-proof is a quick trip to the hardware or liquor store.
Is denatured alcohol the same as shellac thinner?
Usually, yes. Shellac thinner is denatured alcohol sold for that purpose. Read the label for the ethanol content.
Is 190-proof better than denatured?
It's cleaner, with nothing added, and it's the traditional solvent. A high-ethanol denatured alcohol does the job well for most work.
Does the alcohol change the cut?
No; the cut is a flake-to-alcohol ratio. Use the same alcohol to thin a mix that you used to make it.
Does it matter whether the flake is dewaxed or wax-in?
Not for the solvent. See Dewaxed vs. Waxy Shellac for when the wax matters.
All the guides are collected at Shellac Guides. Flakes by grade: dewaxed, wax-in, and button lac.