Shellac Solvent: Grain Alcohol vs. Denatured Alcohol

Shellac Solvent:
Grain Alcohol vs. Denatured Alcohol
Bob Miller explains why you should head
to the local liquor store before mixing
and applying your next shellac finish.

Shellac is a wonderful finish with a fantastic
range of applications and possibilities. It can
range from an easy utility finish all the way
up to the finest of fine polished finishes.
Here is a way to make your shellac finishes
better and easier to use. This gets a little
scientific, but stick with me, it’s worth it in
the end.
It is very important to think about the
solvent used to dissolve the shellac. Most
people simply use commercially available
“denatured” alcohol. Denatured alcohol is
a general alcohol-based solvent used for a
variety of applications across many
industries. Mixed with shellac, it will
produce a serviceable finish. However, it has
some problems when it comes to shellac.

First, there is no industry regulation
regarding what precisely constitutes
denatured alcohol. This means that some
brands are cut with water to increase their
volume, often by as much as 20%.

Second, is that there is no way of knowing
what kind of alcohol was used to produce
the product. Some brands contain methanol,
a cheaper, more volatile, and dangerous
form of industrial alcohol that can be used
to bulk up the volume of solvent. This
inconsistency makes it difficult to predict
the behavior of the shellac both as it
dissolves and as it dries as a finish.

In short, denatured alcohol is an
unpredictable, dangerous, unhealthy, poor
quality solvent for shellac that will make
your finish harder to use as well as shorten
your life. Don’t worry though; I have a solution.

Prior to Prohibition here in the United
States, woodworkers would have simply
mixed their shellac with a high proof, grain
derived alcohol that contained a minimum of
water. It was only after Prohibition that all
of these denaturants were added to make
industrial alcohol undrinkable.
If you’re looking for a pure, consistent
supply of high-strength alcohol that
doesn’t contain this spectrum of
chemicals, think about the bottom shelf at
your local liquor store.
Everclear and Diesel are two brands
of nearly pure alcohol that contain less
than 5% water. They are commercially
available in most states and are the perfect
solvent for shellac, with no denaturant and
a minimum of water.
Once you switch to pure alcohol for your
shellac you will wonder how you ever got
along with denatured alcohol. Pure grain
alcohol will dissolve your shellac more
smoothly and will build your finish more
quickly. So, take a trip to your local liquor
store and pick up some solvent, give it a try
with shellac, and see what you think when
you’ve used a traditional solvent for your
traditional shellac finish.
Bob Miller is a custom furniture maker
and woodworker based in the Charles neighborhood of Boston.

Note: Everclear 190 is not available in all states.
     See below.