Does spray paint ever "expire?"

[louiex2]

I just visited my old house where my sister now lives and she reminded me I had about 20 cans of spray paint still in the workshop and that I should take them with me. The cans are mostly Testors/Model Master and Tamiya; some are still factory sealed but most are partially used and the ball bearing still rattle around in each of them. They are all at least seven years old, most probably older and were stored in an uninsulated shed in the 4 to 30 °C (40 to 95°F) range.

Has anyone had experience with using rattle cans of such a vintage?

[Foghorn Leghorn]

They can lose pressure, when you press the trigger nothing comes out.

Neil

Edited September 7, 2015 by Foghorn Leghorn

[Giorgio N]

Pressure loss can be a problem with old cans. Another problem that can be had is that the paint and the solvent don't mix anymore and when spraying no paint comes out. Don't ask me why, but I've seen this happening...

In any case I've managed to use even older cans with no problem, while I've had problems with more recent ones. Guess the only way to know is give them a try

[louiex2]

Thank you for the quick replies. I hadn't remembered the pressure loss issue. On further inspection, some of the nozzles are clogged so I think I'll start by soaking them in solvent then see which can are still viable.

As a side note, it's pretty clear why I puschased most of the colours- standard AFV and aircraft paints, but there are a several colours I saw and thought, what the heck were you going to pain with that?

[AngstROM]

In a word, YES! Some Tamiya rattlecans I had 'in reserve' for a couple of years (unused) have died the death -paint comes out in 'orrible blobs, despite shaking the can for a near-geological period. Metallics are the worst, apparently, but all types have a finite shelf-life. Which doesn't fit too well with my infinite build schedule...

[PhantomBigStu]

I have a can of citedal black that dates from when I was still in primary school, I'm in my twenties now and it stills fine though not much left

[Knight_Flyer]

Give it a try like the others have said. I have also a mix of old used and sealed cans. Generally used cans seem to be more problematic but so far the sealed ones have been okay.

[Duncan B]

Or try decanting them into glass jars to use with an airbrush if you have one.

Duncan B

[Bounzy]

Hello

 

After googling for spray paint expiration this forum site is the top result. So after i found out what i needed (from a professionel car painter) i figured i would pass on the advise

 

Cause of dead spray paint:

Loss of pressure gas

Clogged nozzle

Thick paint (Separation of chemicals: the solvent that keeps the paint liquid is separated from the paint for a long period, allowing the paint to harden. No this doesn't require oxygen or other breathable gasses)

 

To maintain spray paint:

Keep above +5C at all times

Stay under +35C at all times (just don't leave it in the sun)

Give it a good 1 min shake 1-2 times every year

 

Fixing spay paint:

Soak nozzle in thinner for a little while and apply 10 bar pressure to blow out old residue (i found "the engaging part of the spray nozzle" fits perfectly in a "special" air mattres nozzle for my regular kompressor, making cleaning easy!)

De-can it and use regular spray paint gun/airbrush (Depressurize first with small nail or so), in case of thick paint, it need to be strained first

If you don't have any options you can make thick paint spay out of the nozzle by enlarging the nozzle tip with a 1mm drill (NOT! recommended)

 

Kind regards

The dane 

 

PS sorry about the spelling, am dane. That reminds me, that was a couple of very weird questions i had to answer to become member and share this info. Who under 50 knows anything about planes used in WW2?

Edited June 1, 2019 by Bounzy