Spray Paint Cans - Cleaning after use

[PILOON]

As previously suggested, use laquer thinner and soak well.*

It helps if U have a very fine wire, like from a wire brush, to probe the hole as well.

* I keep old nozzles that have been soaked and air cleaned just for when I take a rattle can that won't work.

 

[bigtiller]

I tried mineral spirits at first, but it just looked like the paint curdled. I'd speculate that the reason it works for you is that they are submerged in liquid until you blow them out with compressed air, thereby denying them the air that's needed for the paint to dry.At any rate, if you find a solution that works, no need to change it.

That must be the trick. It wasn't something I figured out, just dumb luck I guess.

 

[GLyford]

Good thread. I even had a can of WD-4 with some in it that wouldn't work.
Ralph

I tried the technique in this video, and it seems to work (sample size so far, one can). I had to trim some off the end of the valve stem I used so that it would actually press down on the stem, then clean up my knife cut on a belt sander to get a good seal on the top of the can:

 

[Sodo]

Great info. Good tip about reducing the height and beltsanding.

WD40 cans that have stuff and no propellant happens perhaps more than other aerosol oils, and grates on my Irish nature. But I have lots of other specialty oil aerosols and will be using this method to prop them up. I often wonder if they use a permeable valve to leak the pressure over the years. Which is good for resale. And safer for landfills I suppose that the propellant is gone. Except that means more pure WD40 goes to the landfills instead of dispersed to the air but decomposing.

I wonder about putting oxygen into a pressurized oilcan. May be better to use an inert welding gas (not pure Oxygen though). 90PSI is not high but if you leave that can in the sun in Arizona with oxygen inside....? In any case whatever method, it has to be "easy". If you setup to maintain all your specialty oil aerosols at one sitting then it's not a big deal to use Argon for example. Or what gas would be better?

I wonder what pressure you need to push past the seal without depressing the stem?

 

[Billrog]

I've pulled the nozzle off a lot of spray cans and pressed the end of my air hose with a blow gun and re pressured them up. The compressor has min. 120# when I do it . With paint prays after I've used them I blow the nozzles out with air so their clean for the next use.

 

[flyerdan]

I had a brand new WD40 can that wouldn't spray, after swapping the nozzle and it still wouldn't, I used a rubber tip air nozzle to backfeed right through the nozzle and cleared the tube, works fine. I would imagine that it would also re energize any rattle can. Air might not be the best propellant due to moisture and other contaminates, but it beats relegating an otherwise usable partial can to a bonfire bomb.

 

[Gem99ultra]

I too use mineral spirits to soak my spray can tips. Perhaps some brands work and others don't? But I do have paint thinner around here as well.

I suspect though that often spray cans simply ooze out some of their pressure. It totally aggravates me to buy a supply of product x for future use, only to find that I have a full can of product and it won't spray out. I've seen the valve stem method on YouTube, but decided that it was too much trouble to fix a problem that shouldn't have ever occurred. When possible, I've gone to trigger spray cans of things like PB Blaster, WD40, etc.