Isopropyl alcohol

[Lasse Hilbrandt]

I have acces to 99% isopropyl alcohol. But is it suitable for disolving shellac?

[Mel Fulks]

Some here like it ,I think slower drying time has been mentioned. I tried some and it didn't disolve much ,but it was some that I had "salted out" ,not the manufactured stuff.

[Lasse Hilbrandt]

What does it mean "salted out" ?

[Prashun Patel]

Yes it is fine. I use it to good effect. It dries marginally slower than ethanol which is actually a good thing if you are wiping flat surfaces.

If you are deft with your pad or are spraying, then the slightly quicker ethanol can cause less drips.

[Stew Hagerty]

I keep it on hand all the time. I make my own shellac using Everclear as a 2lb cut. The guy at the liquor store laughs every time I go in and buy three big jugs of it. If I'm using a brush, I use it straight, but if I'm spraying I mix some in at 3 parts shellac to 1 part Iso. If I am just reducing the cut for some reason, I will do that with just good quality Denatured. Using the Iso when spraying is very helpful. I found that shellac tends to dry exceptionally fast when spraying due to the very fine mist moving very rapidly through the air on it's way to the target. But then, because I am always afraid of runs, I keep the mixture set very low. More air less shellac = dryer. So I found that adding in the Iso retards the drying just enough that my problem was solved. And hey... It works great on cuts. Yeah, like that never happens. LOL

Oh... and I don't know where you found it, but I get mine on Amazon. I get it on subscribe & save along with other household products shipped to my house on a regular schedule (Man, I love their subscribe & save program!)

Here's the link: http://www.amazon.com/Swan-Isopropyl-Alcohol-99-Pint/dp/B001B5JT8C?ie=UTF8&ref_=sns_myd_detail_page
(http://www.amazon.com/Swan-Isopropyl-Alcohol-99-Pint/dp/B001B5JT8C?ie=UTF8&ref_=sns_myd_detail_page)

[Lasse Hilbrandt]

Thanks, I used to buy ethanol from Germany but now my local store has the isopropyl and I will give it a try

[Allan Speers]

I never thought to try isopropyl. Man, it's sooooo inexpensive.

One big problem with it, though, is that unlike DNA, in which the additives are really bad for you, isopropyl alcohol is itself really bad for you. Really, REALLY bad. Once in the body, it gets turned into acetone by the liver. No need for added methanol, this stuff kills you all by itself.

I'd be curious, though, to know which of the 2 alcohols is more prone to picking up water out of the air. Water in your shellac is the #1 cause of grief when working with the stuff. - Someone should sell it in expandable containers, which could be hung upside-down and thus airless, the way "Box wine" is sold.

Man, how come I 'aint rich? :confused: - probably because I spend too much time on internet forums. :o

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For now, I'm sticking with Graves 190 proof grain alcohol. (At least it's 190 proof when you first open the bottle.)
It's completely safe. Plus it has the advantage of the old "one for the shellac, one for me" schedule. :)

[Allan Speers]

What does it mean "salted out" ?


iso alcohol (unlike ethanol) does not get absorbed by salt. Water does. So, you can pull water out of iso alcohol by adding salt crystals, then decanting or filtering it.

[Lasse Hilbrandt]

I did not know that isopropyl alcohol was poisening

[roger wiegand]

Not sure where you're getting your information. Isopropyl alcohol (AKA "rubbing alcohol") is pretty benign as such things go. The NIOSH exposure limit (PEL) for isopropyl is 400 ppm, vs methanol (the denaturant in denatured alcohol) at 200 ppm and ethanol or acetone at 1000 ppm. Compare to a solvent like benzene at 1 ppm. Acetone itself is unlikely to be very dangerous because it is not very reactive and it is extremely volatile, so you breathe it out as soon as you get fresh air. That said, ethanol is the only one of the three I might choose to drink, despite a beer being at 10 to 100x the NIOSH PEL (6% ABV is ~60,000 ppm if I've done my math right).

Ethanol is the worst among these for water content. Without special measures you can't get it over 95%.

http://www.cdc.gov/niosh/npg/npgd0359.html

[Prashun Patel]

I read the same Wikipedia entry on IPA and this is news to me. I will check our supplier's data again. However, all the safety data sheets I am pulling show it to be only a fire hazard. I have to look into this more now. We use a tremendous amount at work, and we have always followed prescribed OSHA/GHS and supplier safety guidelines for it. We have NEVER been advised that it is poisonous. It's not to be ingested, of course, but poisonous through minor skin contact? THat's a first for me.

FWIW, Rubbing alcohol = IPA + water. They're not the same. Rubbing alcohol may give you problems in shellac.

[Allan Speers]

I guess it depends on who / what article you want to believe.

Here's a scary one:

http://www.poison.org/articles/2012-dec/rubbing-alcohol-only-looks-like-water



Roger, you wrote:
" Acetone itself is unlikely to be very dangerous because it is not very reactive and it is extremely volatile, so you breathe it out as soon as you get fresh air."

That might be true, but when you inhale iso alcohol, it doesn't become acetone until it's in your system, so that acetone cannot be breathed out. As far as I can tell, that's the main danger.

And as far as being "twice as safe" (so to speak) as methanol, well yeah, so what? You're inhaling more than twice as much !
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Whatever the full reality, I think this is a good time to play it safe. I don't use DNA, either. Not even the "good" stuff, and there is no amount of methanol that's safe. I use pure grain alcohol. The difference in cost is not that significant, for a hobbyist, and it's one less thing to worry about.

I suppose one might consider the water absorption factor, which is very interesting if true, but my health comes first.

[roger wiegand]

I guess my point was that on the scale of "toxic stuff" these are all pretty benign, and with only the most modest of everyday control measures (gloves, proper respirator, decent ventilation, safety glasses) can be handled with a vanishingly small danger level. The NIOSH permissible exposure limits are set extremely conservatively, assuming continuous exposure over decades of daily exposure and for methyl, ethyl, or isopropyl alcohol you'd have to be working with them in a pretty sloppy fashion to hit the PEL's even transiently. Yes, without doubt, drinking any of them (Everclear included) will poison you.