I buy wd40 and acetone by the gallon too. But I've never thought of using the acetone in a hand sprayer. I'd be too afraid it would all be gone by the next time I reach for it. Also a bit worried about the seals and O-Rings in the hand squirter. Has anyone actually tried this with good success?
A few years ago, I was watching a tig welding youtube vid, and the guy had one of those fancy solvent dispensers you push down on the plunger with a rag, and it wets the rag, then solvent falls back into the body. I had to have one. So I bought one for about $40-50 on amazon, and it was much larger than I thought it would be, but that's ok, it'll still be handy for all that sporadic tig welding I did. So I filled it up with about $20 worth of acetone, and proceeded to use it while tigging some aluminum together. Imagine my surprise a few weeks/month later when I dabbed a rag on it and nothing came out lol. Not once when I filled it up, did the thought occur to me that it would disappear on me. I ended up giving it to the welder at the shop next door to my work. He loves it.
I keep acetone in the factory steel container now and dispense from there what I need. I tried mixing up a batch of ed's red in one of those lab squirt bottles (I love those things), but it evaporated too. Now I just mix up what I need when I need it.
Glad I bought a dozen cans of brake cleaner the last time PA had them on sale and I was there. They found a good home with the half a dozen I still had from the last time. I should be good for a while. Can't say I use wd40 for much of anything anymore, aside from spraying stuff down after I wash it, which is almost never.
Edit: Forgot to add, I found another good source for acetone in a spray can. The great stuff foam guns have cleaning bottles that are straight acetone with a propellant. More expensive than acetone in a can, but handy in a spray can. Straight alcohol foaming glass cleaner is also handy shop stock too.
Edit 2: holy crap the price of that stuff has gone up, it's now $25 a can at home depot.
https://www.homedepot.ca/product/great-stuff-foam-cleaner/1000499146 Could have swore it used to be $10, which I thought was insane back then, but nessesary if you have a foam gun. Or else you'll soon have two foam guns.