The Stovebolt Site Forums The Shop Area The Tool Chest Rattle can propellant life hack.

I feel good right now. Why? Well, I just got done “Stickin’ it to the man!”
Every now and then I’ll have a rattle can that runs out of aerosol before it runs out of paint.
No, it’s not clogged. It’s just out of aerosol.
Rats! I feel cheated and I want a refund but then they’ll laugh at me for being a Karen/Darren.

I saw this hack on Roadkill.
Add air to the can with a compressor.
Well it really worked out well for me today. I had my doubts.

First, make sure that the straw or nozzle isn’t clogged. If the can is just out of aerosol, then this should work.
I drilled a bigger hole in the nozzle to match the size of the tip of my air tool. I filed mine down to 5/32” and made it as uniform as possible.
Then I drilled a 5/32” hole into the red nozzle until I thought I was right at the turn that goes to the straw in the can. I then drilled a 1/16” hole to complete the connection with the vertical section in the red nozzle.
I started adding air to the can as soon as my compressor started up. I didn’t want to start adding air with it at 30 psi. The shop rag is absolutely essential since you will certainly lose some of the contents as you add air.

That's hilarious.

That's pretty clever. Are they making new episodes of Roadkill or was this an older one?

The one big caveat is that the original propellants are non-oxidizing and compressed air is not. For something like PB Blaster, this would probably be fine for as long as you needed it.

For something like paint, I would expect the clock to start ticking as soon as you filled it. I would be fine using it right away, but I don't think I would refill it and put it back on the shelf.

I'm curious, did it run out of aerosol because you turned it upside down and cleared the nozzle on time too many?

I rarely clear the nozzle that way although it is recommended. I’m lazy I guess.
I think that sometimes it runs out of aerosol because of a slightly leaky valve or reasons I can’t explain.
This hack is probably only good one time per aerosol can. I hate starting a fresh rattle can and throwing away one with a few ounces left.

I agree. It will probably only work once per rattle can. But that’s usually all you’d need it to work since the can is probably on the last 10th of product.

I see stuff like this on the ROADKILL Facebook page.

I am REALlY lazy. I just stomp on the side of the can with swift, and blinding violence, greatly reducing the volume inside the can, resulting in compressing the contents within the can.
Probably much less long lasting as refilling it with compressed air, but I am also going for violent retribution, and revenge against the man.

Been doing this for years. I have an air nozzle that will do the job without modifications. I do it more than once on occasions... until contents are used up.

Another thing that may happen is if you leave a rattle can sitting nozzle side up for a couple of years the heavy solids in the paint will sink to the bottom...right where the pickup tube is. Then, no matter how hard or how long you shake the can when you start spraying, you will get just a wee dribble as the pickup tube opening and everything above it has become clogged since you just pushed the heavy stuff up through it. I wonder if this would work to free up situations like that?

Yes, I know...it would be sensible to store all old spray cans upside down (so the solvents would all be at the top), but I never remember to do that.

How much air pressure can a spray can hold? Is there any chance of it exploding in your face?

John

About 1 out of 3 cans of brake cleaner I use runs out of propellant well before it runs out of cleaner. It’s pretty frustrating. I’ve been meaning to try this.

Good Question

I don’t recommend adding a lot of air. I saw a YouTube video that suggested 10 or 12 psi. However, I don’t think it even needs that much.

........in cold weather I will lay them in a sink with hot water. Depending on the paint I have also did this in the summer. It does make a difference.
........when finished I take my old nozzles off and leave them in a bottle of paint thinner.

.....i leave my air pressure up. A quick shot usually does the trick. If not, give it another shot. Just use good common sense,

the below YouTube video guy uses a modified tire valve to put compressed air into a can. He said about 90-100 psi was max.

www.youtube.com/watch?v=KWIL_jhk-y8

Propellant has no air in it so the paint does not start to oxidize. Air will start that process.

After using a rattle can, I always take off the nozzle, spray acetone or Goof-Off thru it until it runs clean. I never turn the can over and spray. then carefully put the nozzle back on, careful not to push too hard and release more spray. I have probably 20-30 rattle cans and they all work until dry. Some 10 yrs old.