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Hello to All,
Has anybody used this for French Polishing? I just ordered some of their 200 proof. I can't get any 190 proof Everclear here in California, so I'm giving this a try. It's not cheap, but I'll give it a try.
https://culinarysolvent.com/

Never tried it....started with DNA, tried everclear for a while back and forth.....now i'm back to DNA.....been doing FP for about 8-10 years now......could never justify $200/gal.....would not be cost effective in terms of 'better' results.....let us know how it goes!!!!!

I've never had problems using FP with DNA, even though I know it's not the healthiest of substances out there. I never could really tell any difference in the finish between DNA and Everclear to be honest.

Dave

Man! You could have a hell of a party with that stuff!

I use Everclear. I cannot buy it in Virginia but I am in Georgia often enough to stop off at a local package store to buy up enough for the year. 200 proof is over kill and in fact only exists on paper. You cannot get pure alcohol and even if it was real close to 100% (200 proof) as soon as you open the bottle it would suck up every water molecule in the air it could.

I've used laballey.com. We can't even get denatured across the counter here in CA and the Everclear is 120 proof. They've got DA or ethyl up to 200 proof. Pick your poison.

I got a gallon of the 200 proof. I'm in Orange County and happy to share if you want to give it a try! I'm trying to stay away from the nasty stuff as much as I can. Already spent 20 years smelling Bondo, I've had enough fumes for one lifetime!

Ethanol is ethanol, and if it is pure enough it doesn’t matter what is on the label or what purpose it is sold for. You should be good to go. I work in a medical scientific laboratory and I have access to 100% ethanol and have taken some home to use in FP. But I don’t think it was any better than DNA (which we call methylated spirits here in Australia). As Mr McKenna points out the stuff is so hygroscopic that anything that starts out as 100% will quickly become diluted by absorbing atmospheric water.

I handle buying Everclear the same way JF does. We can’t buy 190 proof here in West Virginia, but they sell it in neighboring Kentucky, where I go frequently to visit family.

I separate the ethyl alcohol products to which I have access into three categories. The best, by a substantial margin, is Everclear. I just love working with it. It smells great. Next best are the forms of denatured alcohol that pay attention to quality and the user experience; stuff like Behlen’s Bekhol, which I guess they have renamed shellac reducer. Yes, it has poison in it, but working with it is not that bad. The worst is regular hardware store denatured alcohol, which smells terrible and tends to give me a headache. I don’t use this anymore, if I have a choice (and I do). If you are lucky and it doesn’t affect you, that’s great. But I just don’t like it.

As has been said, 200 proof ethyl becomes 190 proof as soon as you open the bottle. One of my students worked in a DNA sequencing lab, and he gave me a couple of liters of the 200 proof they used there (by the case!) for clean-up. It was not significantly different or better than 190 proof from the store.

Back when I started to learn about FP I had lot of problems, some of which seemed to be linked to the hardware store denatured alcohol. I looked up formulas for denaturing in my dad's old chemistry handbook from college (ca 1940). There are several pages of them, in small print, including things like methyl alcohol, nicotine, ipecac, gasoline, and even shellac. I got to thinking that maybe the issues with the hardware store stuff had to to with the manufacturers substituting ingredients depending on what was cheaper at the time. Sometimes the film would set up but remain sticky, as if there was a high molecular weight fraction of solvent, like gasoline, that stayed on for a while (weeks) after the alcohol had gone away. I went to using 190 proof and that all stopped.

A couple of years ago I ran into some 70% denatured ethyl rubbing alcohol at the drug store, and tried that out. Most of the added stuff consists of a couple of very bitter denaturants and acetone, with water the last thing on the list. Since I tend to add acetone to my shellac anyway to speed up evaporation it seemed like a good bet, and it works fine. Being USP listed I figured it's probably not too harmful (so long as you don't drink it), and they won't mess with the formula arbitrarily. It was a hell of a lot cheaper and easier to get than 190 proof booze, at least until last March. Now, of course, all of the ethyl that isn't being drunk is going to hand sanitizer, but maybe that situation will ease up in a few more months. I still have about half a bottle of the drug store stuff, and a quart or more of 190 proof, so I'm good for a while.

Out curiosity, what is the downside of using 120 proof Everclear as opposed to the 190?

120 proof would be 60% alcohol and probably 40% water. You could make a simple distillation apparatus and boost the percentage to something usable - probably a pint for every quart.

delete

I’m not sure, but I think because 120 has more water it takes longer to evaporate and dry.


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The last 5% of water can't be removed by distillation, so other means have to be used. They used to add in benzene, which binds more strongly to the water, and distill the alcohol off, but there was always some residual benzene, and its a carcinogen. Now they add in quick lime, which binds the water up and settles out as an insoluble solid. You could try that if the added water in 120 proof is a problem. Go slow; add only a little lime at a time and make sure it doesn't heat up too much.

I don't think I would even worry about removing the last 10% of water. I would hazard a guess that those who use 190 proof are actually using 180 proof by the time the polish hits the wood.

This is very interesting to me because I’m experimenting with different approaches to get a very fast “shellac” finish. No pore fill, just wipe on as many coats as possible or in a 3-4 hour period. It’s part of a woodshop class. Would adding acetone help? If so, how much to add?


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Brad—

Do you have the Gore/Gilet books? There is a section in there about making a solution with acetone, alcohol and shellac.

I do have the books but clearly didn’t read that part.

I will take a look. Thanks, Don!


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No worries! It’s in the finishing section of the Build book. The idea is to create an azeotropic solution; the solvents evaporate way faster, which allows the finish to build faster.

But it will take forever to pore fill with shellac only. If you want the fasted pore fill use CA. Aqua Coat is really good too and would only add one day to the process.

How about using saw dust and shellac to put fill? Anyone used this method?
I’ve only used pumice and shellac. Not a fast method, but the results were great.


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I've used sawdust and shellac to fill pores. It works, but it has its own issues. For me, it had a tendency toward gumminess until the shellac hardened up.

In general, using shellac as part of the process of filling pores has the downside of relying on the evaporation of solvent (alcohol). And that brings with it shrinkage. It's manageable, but one should go into pore filling with that in mind and plan for how to eventually get a level surface.

I want to try the azeotropic solution as part of a pumice pore fill and see how much faster it goes. But right now, I am using another way of filling pores: Silver Tip epoxy. I like it a lot.

I've tried a lot of different fillers over the years, and it's really hard to beat the traditional FP fill of pumice and a small amount of shellac. The trick is to use only as much shellac as you need; in practice, start with 'not enough' and add tiny amounts as indicated. Too much shellac and you end up with mud on the surface that is hard to remove gracefully. With the azeotropic solvent solution it builds quicker than you might think. The solvent evaporates to fast you don't have to wait long for the shellac to harden up before applying more. It does shrink a bit more than CA or epoxy fill, but is far easier to sand back than either of those. It's 'way more pleasant to use than CA, and not allergenic as epoxy is.

I use oil-resin varnish for the finish. I sand the FP fill back to the wood, making sure there is no shellac on the surface, and apply three coats of varnish. The first coat soaks into the filler in the pores, and shrinks them a bit. After two more coats I wait a week or two, sand back to level again, then do the 'build' coats of varnish. I get negligible shrinkage after that.

The reason I ask about the 120 proof is because it’s what I used to dissolve my button-lac when taking the Luthier’s Edge French polishing course. I used that same shellac
to finish this box. I didn’t have any issues, but I’m certainly not an authority and don’t want to mess anything up going forward.


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If it works, use it. The shellac will let you know when there's too much moisture.