Acetone vs Isopropyl Alcohol

[SouthernChap]

So, last year when I got my little 7x14, I did the inevitable strip, degrease and clean (and all the other things, natch).

Having by this time, watched a fair few Blondihacks videos, I gravitated to using acetone for the degreasing.

When I was in my workshop, yesterday, I noticed I still had most of a 5l container of IPA (no, not India Pale Ale; there'd be no chance of that lasting in my household!) up on a shelf.

Now, IPA was what I used to use for cleaning and degreasing mechanical parts of flight sim peripherals (joystick gimbals, pedal mechanisms, etc) before I realised I was a terrible sim pilot, both rotary and fixed wing and stopped enjoying myself.

I don't think I've noticed any significant difference in cleaning and degreasing performance between IPA and acetone, although maybe I've not got to the limits of one or the other's capabilities.

So finally the question: can anybody offer any good reason, other than personal preference or habit, for using acetone over IPA, or indeed, IPA over acetone?

(Bonus points for people that answer using their BSc/MSc/PHD or industrial chemist's knowledge to provide a senior high school level answer; which is, as far as chemistry goes, where my capabilities end )

 

[Bone Head]

I'm a chemistry dummy. If IPA is same same as 100% denatured alcohol you should be good. As a side note, if that alcohol's been sitting with the seal broken, it may have attracted moisture from the air. Not good.
Re-reading what I just typed you better wait for @pontiac428 to show up.

 

[SLK001]

Acetone will very actively attack painted parts, while IPA will attack paint less. I would choose NEITHER of these for degreasing, but instead use kerosene or diesel for bulk degreasing. Only for the final wipe down prior to painting would I pull out acetone or IPA. I do like acetone, simply because it can handle almost anything (except plastic) to get it clean. It saddens me as to just how eager acetone is to flee the scene. Pour acetone into a dish for convenience, only to go back to the dish and find it empty. IPA will at least stick around a wee bit longer.

 

[Jim F]

What % is the IPA ?
I prefer 99% for cleaning purposes.

 

[SouthernChap]

I'm a chemistry dummy. If IPA is same same as 100% denatured alcohol you should be good. As a side note, if that alcohol's been sitting with the seal broken, it may have attracted moisture from the air. Not good.
Re-reading what I just typed you better wait for @pontiac428 to show up.

I had to look this up but apparently they're different things: https://www.chemicals.co.uk/blog/isopropyl-alcohol-vs-denatured-alcohol

 

[Martin W]

For a final wipe down either will work for paint prep. Unless you are parts cleaning totally outside, using these products is a huge fire risk. especially if you have pilot lights on appliances. Acetone is very irritable to the skin and lungs.
Martin

 

[SouthernChap]

What % is the IPA ?
I prefer 99% for cleaning purposes.

It's 99.9%

 

[Mauzinette]

I prefer IPA as acetone is unnecessarily harsh for most of the stuff I deal with.

With acetone you have to be really careful around coatings, seals etc.

 

[GeneT45]

I use alcohol for casual degreasing (cleaning parts that are regularly lubricated. It is every bit as effective as acetone in that capacity. Acetone is superior for cleaning metal prior to welding and for removing sharpie / layout die marks.

GsT

 

[ChazzC]

Isopropyl Achohol (IPA), Denatured Alcohol (typically Methyl Alcohol or a blend of Methyl & Ethyl), Ethyl Alcohol and a host of other alcohols all have different properties, and something that dissolves in one won't necessarily be affected at all by others.

I use 90% IPA as it is reasonably cheap and usually available in convenient quart bottles at Sam's (99.8% is 'way more costly, and you have to buy a case of gallons). I use it a a general purpose solvent, particularly to get rid of the film left by Goof-Off after label removal.

My solvent of choice for degreasing is Mineral Spirits, but it's getting harder to find the real thing. Like Kerosene it leaves a light "protective" film, but is a little less hazardous.
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Beginning OT Post:

The solution to Acetone evaporating is to get one of these:


Not cheap (I used a 5% coupon and had a $15 gift card, but still $$; currently $64 at Zoro and $97(!!) at Zoro's Big Brother), but it doesn't leak and has minimal evaporation. I fill as needed using quart bottles from Sally Beauty Supply (100% Acetone, much cheaper than Lowes or HD). The only disadvantage of the JustRite bottle is that you don't have much control over the flow. WIGA2I (a prize to the first one that figures this one out), I'll make a reducing nozzle to stick to fit it.

You can also use these:


They only slow down the evaporation, so not good for longterm storage like the JustRite. I do have a similar, smaller bottle for IPA that I use in addition to a 4oz. squeeze bottle and a 1oz. bottle with a needle tip when cutting Aluminum: