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Anyone using acetone in their French polish mix...........?? Also mineral spirits as a lube...........??
Tom

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It is my understanding that acetone is never sold free of benzene, and thus is a carcinogen. So, I would reserve using acetone for applications where there is not another choice.

The MSDS on my Klean Strip Acetone has no mention of benzene. Am I missing something?

Using Mineral spirits as a lube, on the other hand, seems like you could damage yourself in a hurry w/out full protection.

On my last build, I had a bottle of mineral spirit (I use it as a lube for wet sanding small defects) mixed with my other bottles and mistakenly used it as a lubricant instead of my olive oil bottle. I must say the results were surprisingly good. It made a glossy finish.

Acetone is generally sold as 100% acetone - no benzene/toluene compounds. You are probably thinking of lacquer thinner, which contains toluene, naptha, and a cocktail of various dangerous or unsavory hydrocarbons, chemical stabilizers, and additives to modify how lacquer handles when thinner is added. That said, both are organic, but not in the non-scientific, good way.

From the MSDS for acetone and lacquer thinner:

KleenStrip Acetone:

Hazardous Components (Chemical Name)
100% Acetone {2-Propanone}

KleenStrip Lacquer thinner:

Hazardous Components (Chemical Name):
Acetone {2-Propanone}
Light aliphatic solvent naphtha (petroleum)
Toluene {Benzene, Methyl-; Toluol}
Methanol {Methyl alcohol; Carbinol; Wood alcohol}
Acetic acid, ethyl ester {Ethyl acetate}
Ethanol, 2-Butoxy- {Ethylene glycol n-butyl ether, (a glycol ether)}
4-Chlorobenzotrifluoride {4-Chloro-.alpha.,.alpha.,.alpha.-trifluorotoluene}
Ethyl 3-ethoxypropionate {Popanoic acid, 3-ethoxy-,ethyl ester}
Stoddard solvent {Mineral spirits; Aliphatic Petroleum Distillates; White spirits}

Summary: Acetone...don't drink, bath in, fill water balloons with, breath fumes of, or snort...lacquer thinner ...way, way worse than acetone.

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I think I recall an article in Guild of American Luthiers journal in which Richard Brune said that he no longer uses a lubricant with French polish.

Years ago, the lubricant I read about somewhere was linseed oil.

I've been using a mix of one part 2# cut shellac in alcohol, with two parts acetone. The 'azeotropic' solvent mix evaporates faster than either solvent by itself, so that, even though this is a very thin mix, it builds quite fast. It's particularly good for the pumice fill part, as the fast evaporation seems to minimize shrinkage in the pores.

I worry a lot more about the denaturants in the alcohol than I do about acetone. Most alcohols I've seen don't list that they use to make them unpalatable, and since there's a wide range of things they could use, I'm never sure. Recently I have gotten generic 70% ethyl rubbing alcohol at the drug store that is denatured with acetone, denatonium benzoate, and methyl isobutyl ketone. I can tell you it tastes terrible; even the residue on you fingers is very bitter if you get them in your mouth. Still, I imagine it's pretty harmless in skin contact, give that it's sold as rubbing alcohol. I have not tried it as a shellac solvent yet, but can't see why it would not work.

"I have not tried it as a shellac solvent yet, but can't see why it would not work."

Wouldn't the other 30% be water - X% denaturents ?

Yes acetone cut shellac as alan uses works great.
Not sure about mineral spirit, I use mineral oil.

I don't know what the ratio of water is in that denatured ethyl, but it is the last thing on the ingredients list. There's always some water in alcohol, of course.

The denatured alcohol I use contains 7% acetone. There are no other additives. It is nominally 190 proof ethanol, meaning that it contained 5% water before the acetone was added. Some "190 proof ethyl alcohol" can contain as little as 60% ethanol by the time all of the denaturants have been added. "70% ethyl rubbing alcohol" contained 30% water before the denaturants were added. Here's an example: http://www.med-chem.com/msds/175E.pdf.

I've tried adding large amounts of acetone to my shellac, and never found it to be an improvement. I know others swear by it. I've also heard that it can cause crazing, but this may have more to do with how fast the finish is built up. As far as I can uncover, acetone does not form an azeotrope with ethanol. I don't know that it matters. Acetone flashes off plenty fast all by itself. In fact, that's what I don't like about it. For the same reason, I don't care for 200 proof ethanol. It doesn't give me enough wet time. Maybe I just haven't spent the time to acquire the touch. I'm not sure that the potentially lower boiling point of an azeotrope would necessarily mean faster drying at room temp. Pure 190 proof ethanol is an azeotrope. It boils at a slightly lower temp than 200 proof. But 200 proof still dries much more quickly.

Acetone doesn't seem to be particularly toxic. Depending on how it is produced, it can contain trace amounts of benzene. The same thing can be said of 200 proof ethanol. Benzene is bad news, but there are other sources that are probably more of a risk to all of us. There's more info on acetone here: http://www.atsdr.cdc.gov/toxprofiles/tp21.pdf

I am trying to avoid chemicals in the shop, as best I can, and I FP with a glove on my right hand.

Startex brand alcohol's msds shows a fairly low mix of denaturants, so that one is my choice.

Since I get a good FP job with alcohol alone, using cold pressed Linseed Oil for lube.

Acetone has always seemed to me a dangerous one to mess with.

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