Why enamel paint turns to gel after a month or so?

[skymnky721]

This may have been covered somewhere else,,couldnt find it. Anyways,,why does testors enamel bottle{small size}  turn to a gel-like glob after a couple of months?  I store them indoors,,away from direct sunlight,,so there not getting too hot,,and the weirdest thing is  not all colors do this!  Some I have  Ive had for  a year or so,,and there still fine{aside from having to add a bit of thinner to help flow better}  I dont get it.   Any ideas?

[Can-Con]

If you clean your brushes with lacquer thinner and it gets into the paint off your brush that will happen.

 Doesn't take much either, just the brush not being completely dry after cleaning and dipping in the bottle can do it.

It's happened to me. 

[StevenGuthmiller]

I've had it happen to me too.

I've concluded that Testors bottle enamel does not play well with plain old paint thinner. (mineral spirits)

I use it all of the time for cleaning brushes, etc, but if you use it for thinning the paint, it seems to really speed up the "gelling" process.

As Scott said, it only seems to happen with certain colors.

 

Steve

[Snake45]

I've never had it happen thinning with lacquer thinner. In fact, I've used Testor/MM paints that I thinned YEARS ago with lac thinner.

OTOH, I HAVE had this happen thinning with naphtha (lighter fluid). And within days, or no more than 2 weeks.

I've also had unopened old Pactra paints do this. Apparently they thinned at least some of them with naphtha.

[skymnky721]

Thanks for the info,,Im considering switching to all Acrylic  paints at some point,,might have better luck