Acetone vs Isopropyl Alcohol

[Shotgun]

A fun tale. Aside from the common names for ethanol, grain alcohol and ethyl alcohol, there are some less well known names. I had a chemistry professor in college that had previously taught at the Air Force Academy. The ethyl alcohol in the lab had an excessively high evaporation rate. The lab manager changed the name on the bottles to ethanol and the evaporation rate dropped for a while but then resumed its former level. He then changed the name to methyl methanol and the evaporation rate dropped for a while longer but eventually resumed its former level. The name was then changed to methyl carbinol and the evaporation dropped to zero.

I worked a student job in the chemistry lab while at NC State. One of the janitors came into the lab, saw the alcohol label, and had a good time. . . for a short while. First he went blind, and then died from the methanol.

 

[RJSakowski]

I worked a student job in the chemistry lab while at NC State. One of the janitors came into the lab, saw the alcohol label, and had a good time. . . for a short while. First he went blind, and then died from the methanol.

I have heard of that happening. The uninitiated would confuse methanol and ethanol. The evaporation that I mentioned above was suspected due to the janitorial staff as fairly close tabs were kept on the stock during lab sessions. All the ethanol that we used was undenatured. Denatured ethyl alcohol is pretty much useless in an organic chemistry lab. The same was true when I was working professionally. As a state institution, I believe we were tax exempt.

 

[Larry$]

There are a lot of ethanol plants making gasoline diluents. I wonder how that is controlled?
Vevor sells distillers for home use. Make your own solvent, or....

 

[SouthernChap]

I worked a student job in the chemistry lab while at NC State. One of the janitors came into the lab, saw the alcohol label, and had a good time. . . for a short while. First he went blind, and then died from the methanol.

Well now, that's a cheery anecdote.

 

[Janderso]

Acetone will very actively attack painted parts, while IPA will attack paint less

SLK001 is so right.
I got to the point where I mix 25% acetone and 75% alcohol. It's not as harsh on paint but still is a good degreaser.

When I was working they banned Trichlor. 111. That was good stuff!
We went to hexane/alcohol and (acetone 10%) mix.

 

[bill70j]

When I was working they banned Trichlor. 111. That was good stuff!

I agree. We used Trichlor (trichloroethylene) as a glassware degreaser and as an extraction solvent in a materials test lab in the late 60's.
My US Army MOS had a great position entitled "lab manager" in a Corps of Engineers test lab in Seoul. The assignment lasted about 14 months then you rotated out. But there was a great contract lab technician who we called 오씨 ("Mr. Oh") who had been there forever and who saw a number of us come and go.

I took this picture of Mr. Oh because we all thought he was kind of like a Chicken Little for bringing his own PPE to the lab and ALWAYS wearing it when using trichloroethylene and benzene. Turns out he was quite prescient and we were all quite foolish.

Mr. Oh doing a filtration in our quonset hut lab in Seoul way back when

 

[David2011]

It was briefly mentioned early in the discussion. I like mineral spirits for degreasing. It's effective, there's not a lot that it damages, it evaporates fairly slowly, the odor isn't terribly strong and if the part is truly clean, there will be no residue left when it does evaporate. It's readily available and not real expensive. I've found partial and even full cans at garage sales at great prices. If it's left to rest without moving most contaminates will settle to the bottom and fairly clean product can be poured off the top. It's also my favorite for cleaning freshly machined parts.

Simple Green and Awesome are very effective at degreasing at full strength or diluted 1:4 or so. In an ultrasonic cleaner I dilute it 1 part in 10 (1:9 ratio). I just cleaned up a milling machine vise that had years of cutting oil embedded using Simple Green diluted 1:9. At 150°F for 30 minutes it got almost everything off of every part of the vise. The only piece that wouldn't fit in the US cleaner was the body (6" vise) so I heated the solution in the US cleaner, increased the strength to 1:4 and cleaned it in a plastic bin using a parts brush. A final wipe down with paper towels and mineral spirits had everything clean enough to paint, which is pretty darned clean.

If you insist on using gasoline and don't like the odor that lingers for two days, use aviation gasoline. When it evaporates the odor is gone. I worked on light airplanes at one time and the only thing we used gasoline for was removing silicone sealer. For everything else there is a safer alternative.

 

[bill70j]

, use aviation gasoline. When it evaporates the odor is gone. I worked on light airplanes at one time and the only thing we used gasoline for was removing silicone sealer. For everything else there is a safer alternative.

Just need to take extra precautions -- considering that avgas still uses lead additives --I think.

 

[Larry$]

Speaking of gasoline, just filled tonight $2.549 @ Sam's Club. And I get another 5¢/ gallon credit on my card to spend in the store. (Plus membership & Sam's Mastercard) Never thought I'd see gas this cheap again. Used to always be an open pump @ Sam's but not now. There is often a short line at all 12 of the pumps. People like cheap gas!

 

[Janderso]

I agree. We used Trichlor (trichloroethylene) as a glassware degreaser and as an extraction solvent in a materials test lab in the late 60's.
My US Army MOS had a great position entitled "lab manager" in a Corps of Engineers test lab in Seoul. The assignment lasted about 14 months then you rotated out. But there was a great contract lab technician who we called 오씨 ("Mr. Oh") who had been there forever and who saw a number of us come and go.

I took this picture of Mr. Oh because we all thought he was kind of like a Chicken Little for bringing his own PPE to the lab and ALWAYS wearing it when using trichloroethylene and benzene. Turns out he was quite prescient and we were all quite foolish.

Mr. Oh doing a filtration in our quonset hut lab in Seoul way back when

View attachment 473774

Reminds me of being exposed to MEK -Methyl Ethyl Ketone, when I was in the baseball business.
We used it to clean the ink off the pad press etched plates. The fumes were ever present.
We all should have been using some sort of breathing alternative.