Tonight I twisted off the cap of an unused bottle of MM insignia blue enamel for a project. Lo and behold there was the typical quarter inch thick layer of blue rubber just under some clear substance in the bottle. That ended my plans of getting paint down tonight.
What is that stuff? Why does it do that? Is there a way to revive the bottle? This bottle was unused and unopened since I bought it about a year ago. Really miffs me to find this every so often. I always make sure my caps are clean and on tight.
No hope for the dead soldier that never fought. Even though you never opened it, it seems it’s time has expired. I take it you couldn’t shake it nor stir it up. I’m not sure why it does that, but I have had a few bottles that just expired before I could use them.
That “stuff” is polymerized paint, with the pigment. From your description, it is not recoverable. Some paints just settle hard, but you can redisperse them with thorough stirring, NOT shaking. But if the stuff is ropey, gooey, and fairly coherent, your best bet is to discard it.
It did it because that’s what paint does—it just did it too soon. It is possible that the paint is very old. Who knows how long it sat in a warehouse, on the shelf in the store, etc., or what conditions it experienced in transport or storage before you got it? Cooking in a semi-trailer for a few days in the heat can do it. It sounds like there was a loss of solvent. The bottle should have been essentially full. Solvent in a paint does two things, basically. It reduces viscosity, and it slows or prevents polymerization of the binder until it evaporates.
If you can, take it back for exchange—the cost of model paint is cosmological, in the Carl Sagan-ist sense.
Some brands are more prone to this than others. One of the reasons I’m so fond of Tamiya and Polly Scale is that they seem to have slightly fantastic long term stability (and prices to match). I’ve heard Gunze is similarly resistant to the ravages of time and elements, but have little experience with it, as it didn’t seem to fit my painting methods (strictly a matter of taste, here).
I love Tamiya acrylics because they seem to last forever. I just found some 1/3oz bottle that I had purchased about 3 years ago. The contents had settled, but I just stirred them with my electric stirrer and they as good as new.
In fact, I just sprayed a few of them through my Iwata last night and they worked perfectly.
Ditto, I have a bottle of Tamiya paint that I bought in 1989 and it works fine. Enamels just don’t seem to have the longevity that acrylics have. Your result may vary!
Thanks guys. I also have some very old Tamiya that is just fine. I just came from the hobby shop with replacements for my bottle of rubber so tonight I should be able to get back on schedule for paint.
Woo-Hoo…I think I have the high score (so far). I have some Tamiya acrylics circa 1982-83 that still work fine. I think they could use this stuff as food preservative.
Ahem! There were no acrylics in 1901. And I happen to know there was no “you” in 1901, when your parents weren’t even gleams in your grandparent’s eyes! [(-D]
I know because that was when we finally could stop walking uphill both ways to wherever we were going, barefoot, in subfreezing blizzards year-round…yadda yadda yadda…
I actually used to walk to school uphills both ways. There usually wasn’t snow on the ground, nor was it chest deep (unless one fell), but my house was on one side of a hill, and my school was on the other. Uphill, then downhill to school, and then reverse the trip to get home. I did have shoes, but they were made out of animal hides.