Shelf Life of Paint & Primer

[Southern_Cal]

I'm coming back to my 1/285 collection after a pretty healthy (i.e. years) absence. How do you determine if the primer & paint you've stored for a long period of time is still serviceable or if it should be replaced? I've got bunches of AFV's & infantry that need a paint job and Ritter's & Stockton's posts have me raring to go...

thanks,
-Nadir

[Donald M. Scheef]

1. Try to open the bottle/tin. If the container can not be opened without destroying the container, the paint is NOT usable.
2. If the container can be opened, check to see if the contents are liquid. If it is completely solid, the paint is NOT usable. It's not worth the effort to try to add the appropriate carrier and try to re-suspend the pigment.
3. If the contents are liquid, check to see if the pigment has separated from the carrier. If they have separated, you MIGHT be able to re-suspend the pigment my vigorous mixing. If you can not get the pigment re-suspended, the paint is NOT usable.
4. If the contents are liquid and the pigment is suspended, try the paint on a sample piece. Observe the results. If you like the results, the paint IS usable. If not, throw it away and get new.

Because my interests in specific topics change over time, I have been through this process before. I have had paint sitting on my shelf for over five years that was usable when I got back to it. On the other hand, I have sometimes opened a container, put it away, and then found it to be rock solid a few weeks later.

Good luck.

[Mk 1]

I tend to save everything for later re-use.

Some of my paints have been in the box for not just years, but decades.

Donald' advice is just about right. But for myself I am somewhat less thorough than his multiple steps suggest.

First, there is no paint container I can't open. I have an old pair of pliers in my paints box, and I use it often to open up bottles of paint. If needed, I have vice-grips in the toolbox. I often run the cap under hot water to soften up any dried paint that is holding it shut. I have even tried briefly microwaving -- BE CAREFUL NOT TO OVERDO THIS TECHNIQUE! About 5 seconds is the longest I've ever done. The metal lids are VERY HOT in just that time. BE CAREFUL.

But they all come open eventually.

I have had some paints dry-up completely. A hard (tappable) lump. At that point ... forget it. Toss it. Move on.

I have had some paints seperate/dry-up to the point where the pigment is a rubbery lump in the bottom of the bottle/tin. Put a small amount of warm water (for acrylics) or thinner (for enamels) on it, and try to "stir" the liquid into the pigment. If it won't stir it, if it just sits on top, or flows over the rubbery surface ... forget it. Toss it. Move on.

If you can get the rubbery pigment to accept the water/thinner, you can turn it back in to paint. More water/thinner. Stir. More. Stir. You've got it.

Most of my paints are Polly-S acrylics. Some are Testors Model Master enamels. Some are regular old Testors enamels. They come in glass bottles, so I can see their state. My paints seperate all the time. Every time I take the box out to paint with them, some are seperated. I give them a vigorous shake, and put them back in the box. If I'm actually using the paint, I'll give it a vigorous shaking before I open it, then give it a stirring with the back of the paintbrush. All just maintenance.

I have some paints in my box that date back to the 70's and 80's. Still serviceable enough.

[jb]

I still have Humbrols from the 80's that are still good...

[Der Kommandeur]

Me too! I think the oldest tin I have is Humbrol 11 ... which is silver or aluminium ... which must date from late '80s ... don't use it much (obviously) ... but it's still going strong.