Question 70% isopropyl alcohol

[signmania]

Anyone know where I can get some on the cheap? Apparently the local stores are out. I accidentally bought ethyl alcohol (no I'm not drinking it). And it's an odd smell. Like GIN.
I normally buy alcohol at walmart, but with this silly coronavirus, I'm having a hard time locating it. That being said, we are growing as a business and will be needing more of it. I was fine when it was 1.96 for 32 oz at walmart. I could pick up plenty. But it seems like when I look online for larger quantities, they are a bit more expensive. Does anyone have a site that they go to buy it in bulk?

Thanks.

I've never had a problem with denatured (I get it on sale at Menard's). If the vehicle is relatively clean I go over the surface with Sparkle (no ammonia in it!) and then finish with denatured. I do wipe down the surface again with a clean dry towel to make sure there is no haze left behind. I've never had a problem in 30 years.

 

[signbrad]

Can anyone weigh in on whether the denatured alcohol works as well?....any concerns substituting this for isopropanol?

Back in the day, many shops used denatured alcohol as it was readily available and inexpensive. The main use for it in all the shops where I worked was as a wipe for plastic prior to back-spraying with translucent sign paints. We always cut the alcohol with water or it would streak. I usually cut it 2 to 1 which is roughly the same concentration as rubbing alcohol. Standard practice was to wipe only with a chamois to avoid introducing static which created havoc when spraying (and even when hand lettering). But I eventually switched to the synthetic chamois substitutes that came in a plastic tube at the auto parts store. They seemed to work as well and the tube kept them from drying out. Laundered them periodically or they would smell pretty bad. Conversely, paper towels and shop rags always created static.

The three commonest alcohols used are methanol, ethanol and isopropanol. All are simple hydrocarbon molecules, but methanol is the simplest and cheapest. It is, however, highly toxic. Its main use is as fuel for race cars. It is also not uncommon to add a tiny amount of methanol to adulterate ethanol to make it "denatured." Without adding some kind of toxic chemical to ethanol, you would be able to drink it. All three of these alcohols are miscible in water, though only methanol is miscible in both water and oil. Alcohols are used as solvents in inks, paints, adhesives and many other things. Mixed with water, alcohol is an excellent cleaner that is not harsh. Used in a mix with some of the lacquer thinners (toluene, xylene, etc.), it becomes a decent paint stripper. The old T4000 Griplflex paint stripper for plastic faces was basically an alcohol mix.

None of which, of course, answers Chuck's question.

Brad in Kansas City

 

[TimToad]

If we can't find the 70% or 91% at our local Big Lots! or other source, our Denco Sales has the 99.50% isopropanol for $75 per gallon, which is 200% more than it was not that long ago.

When forced to go that route, we make a couple different concentrations out of it and can usually stretch it to several gallons of liquid in three or four different strengths.

 

[rjssigns]

We have 99% isopropyl wipes in the lab. Goes something like this: Bring container as close as possible to what you need to clean. Pull wipe from container and aah crap its dry, grab another and move fast ahhh crap. End up grabbing the squirt bottle and KimWipes.

 

[Mike Paul]

I usually buy 91% Iso by the case to prep vehicles but you cant find any grade isopropyl around here in the stores.
Just bought 10 gallons of Medical grade 99% Iso from a local janitorial supply store. Runs about $17 per gallon.

 

[Bingleardicus]

Best way is to get a gallon at home depot.

should be near the paint

 

[Mr. Signboy]

I buy mine from ULINE, they have 70% and 99%. Most of the small sizes are sold out but you can still get 5 gal cans, which is a better deal anyway.

 

[Jeremiah]

I use Denatured Alcohol. This summer I was in a hurry, and got it on my skin. By the next morning, my hands hurt and they puffed up to double sized fingers. Almost could not work. It took a bit over 24 hours to go back down in size. I now aways wear rubber gloves when I prep a sign surface .