Proper acetone procedure

Lack, I went to one of our myriad of thrift stores and bought some small glass glasses, they also had a stack of round glass ashtrays which fit pretty well over the top of the glasses. It is not an airtight fit but the evaporation factor has been minimal. My investment in 4 glasses and ashtrays was $2 (plus cleaning them). My wife and daughter (and past GF's) have used acetone as long as I can remember as a nail polish remover, with it coming into contact with their skin. I'm sure it's probably not great for you to get on your fingers, but it's not the end of the world either. Make sure the stuff you got from the pharmacy has no secondary ingredients, my wife's bottle of 100% acetone (for nail polish) has two other ingredients listed on the back besides acetone, don't remember what they are and I'm to lazy to go upstairs and look-LOL!

 

Log in or Sign up to hide this ad.

I have a small collection of shot glasses that work really well for acetone baths. I pick one that will keep the coin standing up a bit so only the edges actually can touch the glass. This takes very little acetone for each bath and you get past some of the worry about the fumes and fire danger. A larger glass or an old glass lens from a flashlight work really well for a cover. As you pour off each bath of acetone, you can tell if the coin needs more.

With that said. Not all coins can be helped with acetone. PVC needs to be removed but that may leave the coin looking worse. The surface under the PVC or other organics can look really nasty and even shall hits will show much more. You just never know, but over the years you get better at guessing the results.

 

Whoof! Those are "chemical-supply-company" prices. The problem is that you don't really want to scrimp on the amount you use -- I tried a two-stage rather than three-stage dip, in small Pyrex bowls, and I still ended up using probably two ounces in each bowl. Four ounces won't take you very far. You might consider using that only for your final rinse, and using hardware-store acetone for the first stages.

Like I said, I used little Pyrex "dessert cups". Shot glasses would be great if your coins fit into them; I was working on half dollars, and I think they wouldn't quite fit.

Another poster warned against using dishes that you also use for food. In general, that's a good policy when you're working with solvents or household chemicals (even more so with lab chemicals), but acetone is pretty benign. If you must, rinse the dishes with acetone, then run them through the dishwasher, and they should be perfectly safe.

Doug recommends using your (bare) fingers to transfer coins. I still worry that that would add contamination, since the acetone would be drawing oil out of your skin, and I wonder if that's the source of the white haze on copper he's seen.

DON'T use "rubber" or latex gloves. They'll either leach contaminants into the acetone, or flat-out dissolve in it.

Metal tongs would work, but who wants to grab a nice coin with metal tongs? I've got a couple of tweezers with soft coatings on the end, but I tried putting acetone on one, and it changed the finish of the coating -- I'm not sure whether it was starting to dissolve the coating or just leaching out some plasticizer, but I decided not to trust them in the bath with my coins.

I ended up using wooden chopsticks. I'm not sure I'd recommend it, though -- I'm pretty good with chopsticks, but picking up a coin (particularly a worn one with rounded rims) was a major challenge.

If you splash acetone in your eyes, that's bad, but I've never come close to doing that. The vapor will sting your eyes and/or make you dizzy if you lean right over a big bowl of the stuff; don't do that either. If you get it on your skin, it'll dissolve out the oil; soak in it too long, and you'll have dry, cracked, and irritated skin. If you want to injure yourself or poison yourself with acetone, you actually have to work pretty hard at it.

The big danger with acetone is FIRE. Its vapor is EXTREMELY flammable, and it has a low boiling point/high vapor pressure, so it puts out a lot of that flammable vapor. Use it in a well-ventilated area, and keep it away from ignition sources (sparks or open flame). Yes, sparks from static electricity count!

 

The last 3 posts have answered my final nagging questions. How to seat the coin for its bath, what to use to place and remove the coin from the container. Thanks!!

 

HI if u can find a glass jar with a rubber seal it will not evaporate

 

Well, I re-did the half cent in acetone today, no more green at all, but I still have the "whitish haze" even after rinses in acetone and distilled water. May just be the coin, it is my first try with a copper piece. Bust half dollar and dime cleaned up nicely.

 

Not immediately, but the acetone will swell the rubber, ruining it in short order. And if the rubber contains any sulfur (as most rubber does), there's a significant chance that some of it will leach into the acetone, leading to... surprises when next you use that acetone to clean silver or copper.

 

That depends on which rubber. Butyl (fairly common) and polysulfide are both good as well as teflon.

 

Teflon's good against almost anything, but it's not rubber.

I didn't realize butyl and polysulfide were acetone-resistant. That's good to know; now all I need is a way to tell whether a given seal is made from one of them...

 

Ok, I have just done 4 separate runs of PVC removals in the last 6 days. For the initial 24 hr. soak I covered the coins in about 1/4" of acetone, in small glass containers (1 1/2" dia.?) these were covered with glass ashtrays, not airtight, but not open either. My evaporation loss in 24 hr. was negligible. It would appear that as long as you make some attempt to cover your container with something inert you will be fine, it's not like the acetone is the precious part of the equation-LOL.

 

i thought we were not supposed to discuss rubber on this site?

 

I have tried both and quit with the water, it can leave spots as it dries, acetone doesn't from what i have seen.

 

Would you reccomend using Acitone on a 3-cent nickel with a pretty corroded reverse>

 

can't say, I have only used it on silver coins. it won't do anything for corrosion but may lighten up/remove any dirt/ grime that has collected on it. nickel is a pretty tough metal hard to hurt it i would think. try a modern one first.

 

Thanks! I'll try with one of my AU condition later year buffs with grime and dirt first, then if it works, go to the 3 cent.

 

that is very true what you need is a ear bud that soaks the water but doesnt touch the surface

 

What?

Are you talking about the little sponge covers that go on earbuds? I guess they could be used as an absorbent, but please make sure you only try this with unused​ ones...

 

What about an old ROMAN COIN that is very brown and crusty that has been sitting around for 1400 years that you don't really care about