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Acetone and ATF Don't want to mix

I have read on a few posts of people using a 50/50 mixture of Acetone and ATF (Automatic Transmission Fluid, I presume) to make up a superior penetrating oil. I finally got around to buying some Acetone and tried to mix up a batch to have on hand. I have it in a small plastic bottle and the two won't mix. The thinner acetone just sits on top of the heavier ATF. I shake them up, then a short time later they are separated again. It's like oil and water. Can someone who has used this stuff tell me what I might be doing wrong here?
 
The stuff will separate if left sitting for long just like lots of other chemicals do. How many liquids do you use that all say shake well on the label? Same here. Shake well before each use.
 
There are other threads on the efficacy of various "stuff" to break parts loose. This is said to be the best by some. I've used it since the summer & have no opinion as yet. Been dousing a frozen engine every so often & yes, it's obvious the mix shows acetone not to be a solvent for ATF as there are mucho bubbles in the mix which get smaller when shaken. I'll ask my chemical engr son what the deal is & report back.
 
Acetone is a great chemical. But, it must be used in the correct applications. Using it as a penetrating fluid is a waste of time. The vaporization rate is very high. It is also flammable. It does NOT mix with oil. Not to mention that it is also a mild paint remover. Get a drop on your gas tank, and you will be very upset. It is also dissolve certain types of plastics. My advice to you is to stick with using PB as a penetrating fluid. You can get it at any auto store or even Walmarts.
 
I have to agree with 23217. I never used acetone for anything around my shop for the reason that it IS a potent material. I am glad to be reminded that it would instantly dissolve very expensive paint on the bike if I accidentally splashed some on it. Likewise, I myself had questioned the use of this mixture for the same reason mentioned: it evaporates very quickly, leaving only the ATF behind. I couldn't see the point of it. On top of all that, the fumes seem pretty deadly. Well, at least I only have $6.00 in the quart of it. I value my paint, and my health too much to fool with this homebrew. Time to go back to Kroil or PB. I thank everyone for their good advice. You may well have saved me a $1000 repaint job.
 
I would not describe acetone as toxic. If I recall correctly, it has a lower flash point then alcohol. Both carry a risk of combustion. Chemist use acetone to clean glassware. It is great for removing a large variety of chemicals from glassware. It leaves glass sparkling clean.

If I had two metal mating surfaces I wanted absolutely clean without the risk of a residue, I would use acetone. Many people use alcohol to clean surfaces. But, alcohol leaves a residue. Acetone is a better chemical to use. I like acetone. But you need to use it in the right application. And, you need to remember that it does dissolve certain plastics and paints.

I can understand why someone might think that acetone would be a good penetrating fluid. It does have the ability to dissolve and remove a large variety of compounds. But, it carries a number of undesirable problems. Additionally, I think that PB and a couple other products work better anyway. Your not crazy for considering it. In theory, it appears to be a good idea. But, in a practical application it does not work out well.
 
Over on the LT website one of the members posted the results of a controlled study which compared all the major penetrating oils vs. the ATF/acetone mix. The home brew won hands down. Yes, acetone will pull up your paint but from what I saw it really does work. So I use it where there's no chance of getting it on the paint. I've also tried mineral spirits and ATF. That mix works well.

http://www.bmwlt.com/forums/showthread.php?t=53261&highlight=acetone/atf
 
Like I stated earlier, acetone has many good properties for penetration and dissolving chemicals. I am not surprised that it does work. I have used it myself for bolt removal in limited and controlled situations.

While I have not read the original article, I do have a number of issues with the findings.

First, the same piece of metal corrodes at different rates in different areas. So, when they say that they "scientifically rusted" the bolts for the test, I have to question this. I think it is impossible to get all the bolts to rust at the same rate and have the same difficulty in removing. I am sure they did multiple runs. But, I didn't see any correlation coefficients in their findings. I would suspect that it is high. If it is high, then the study if flawed.

Second, some penetrating fluids can penetrate at a higher rate. I wouldn't be surprised that acetone would penetrate at a high rate. But, penetration rate is just one factor. You may have a fluid that penetrates at a slower rate, but removes more rust and chemicals over time. So, if you let it sit overnight, it might work better. Acetone will not work for long wait periods because of it's high vaporization rate. So it becomes like comparing apples to oranges.

Let me give you an example. We have a truck at work that was driven through some heavy salt concentration during the winter. It was then stored over the summer. When winter approached, we discovered that the spark plugs hex head had corroded to a complete round surface. This also included the head bolts and many other parts. We had to cut the head bolts off with a disc saw. We tried to use acetone, with no results of removing any of the corroded spark plugs. We then allowed PB to soak overnight, and this removed two of the four spark plugs. For the last two plugs, we had to chemically clean the heads; Knock out the center; Then peen the side; Drilled it; And finally rethread the hole with a tap. This was just one issue with this truck. Acetone was worthless on this particular project. PB worked much better by allowing it to soak for an extended period of time. Having said this, I wouldn't hesitate trying acetone again. Different problems require different tricks. But, in my experience acetone has not worked as well as other products.

Third, penetrating fluid needs to do multiple actions. Removal of rust, corrosion, grease (anti-seize). Lubrication of the threads. Some corrosion of the metals to counter-act expansion and locking of metals. Acetone might work well in certain situation, and not so well in other situations.

Forth, the study was for machine shops, and not for garages. Most machine shops get head, blocks, cranks, and other metal parts. They don't have to worry to much about paints and plastics. Many shops have recycling fans and filters for dust and chemicals.

Fifth, most automotive machine shops have other good techniques for removing bolts. Like corrosive chemical baths, heating, peening, etc to remove bolts. Penetrating fluid is used, but they have better methods of more stubborn bolts.

I like acetone. Actually, I like it a lot. But, it comes with some serious issues. Combustion is my primary concern. Hot engines, furnaces, stoves in the house, electrical arcs in light fixtures are just a few ways to have a large explosion. The other concern is the vaporization rate. It evaporates at an extremely high rate. If your garage is closed, you can easily fill your garage or home with acetone and not even realize it. This can lead to an explosion or corrosion of parts.

Acetone is a tool in your shop. But, it is not my preferred tool for removal of bolts.
 
Please wear chemical resistant gloves anytime you handle acetone or acetone based products. I have read that acetone is a carrier which facilitates skin penetration by other compounds.

Some of you more scientific types might be able to confirm this.

Tom
 
Please wear chemical resistant gloves anytime you handle acetone or acetone based products. I have read that acetone is a carrier which facilitates skin penetration by other compounds.

Some of you more scientific types might be able to confirm this.

Tom

Yet females rub it all over their hands and feet regularly, as nail polish remover is Acetone

Funny, or sad story dependent on your view. Several years back as part of an ongoing monitoring of chemicals around a Kodak plant in Rochester, they found miniscule traces in soil 20' underground near a residential street that bordered the plant. It was from a rail car spill that happened back in the 50's or 60's, I believe.

Well many of the home owners saw this as a way to get the deep pockets company to pay them BIG bucks to buy their houses. The one woman they interviewed on the news, that was complaining she had all these health problems, the biggest was it looked like she was on a "see" food diet (pun intended) and surely her health issues were related to the 3 PP billion they detected. All the while, I am looking at her hands, and long nails covered in lacquer paint (nail polish), thinking that probably 2-3 times a week she rubbed almost pure acetone on her fingers. I wanted to pick up the phone and call the newsroom so bad.
 
The human body naturally produces acetone and excretes it through the kidneys. It is considered a fairly safe. I don't see the need for gloves. You can check out the MSDS from one of the manufactures. You can read an easier description on Wiki .
 
Why mess with Nature

We may produce acetone as a byproduct of biological existence but it certainly doesn't make it safe. This stuff is rapidly adsorbed though your skin and airways either through direct contact or fumes. Its also highly flammable and in a sealed container its explosive. Of course many garage chemicals or compounds are just as harmful but why add to the list of garage chemicals with such little benefit. If my can of PB Blaster doesn't work then then there's no need to be gentle with it so Break out the heat or the big tools. I am comfortable putting a little heat to a bolt coated with PB but won't even light one up if acetone or gasoline is in the area, call me a wuss but I like my stuff and don't want to burn it up!!!
 
Well, in defense of myself in this thread: There was a recent discussion thread here r.e. use of various "stuff" to break loose a frozen engine & other locked parts. Several persons that sounded to be knowledgeable or at least IMO,worth a try types, said the ATF/acetone mix was the best or at least worth trying. Like many with a shop full of "stuff", to include both those items, I have been trying it on a locked up airhead engine. So far hasn't done the trick & I'm next moving to Kroil & PB for their "magic" properties. It had my ATF oil gun tied up with the mix for one thing. ATF makes for the cheapest light oil for general shop use that you can find. I also use it on guns as a lubricant. I can report that (lifelong woodworker!) that it causes no harm to the finish nor does it gum up on the action parts. While it lacks the solvent action & high pressure qualities of some gun lubes, it does lubricate well just like it was intended in you tranny.
To say I wouldn't use something in the shop that removes paint is not going to happen! Anyone that does body work knows that lots of "stuff" will ruin a paint finish, eat plastic, you name it.Dirt,silicone,many solvents,waxes ,etc., all have there issues around paint work as does the worst of them all around cured paint-brake fluid. Everything has its uses or it wouldn't be there.
As this thread progresses, I'm hoping to hear of the next magical penetrating fluid. I used PB & another I've forgotten , every day when an industrial mechanic(Goodyear bought it) and can't say one was any better than the other. There was no sitting overnight,just squirt and beat and pull...
 
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