Airbrushing with.... sludge?!?!?!!!

[AJ Kleipass]

A weird thing happened to me today. I went to airbrush a model with some Tru-Color paint - #822 flat railroad tie brown - and instead of getting paint I ended up with an airbrush that was clogged from the get-go with sludge.

I'm not a novice with the airbrush, nor with the Tru-Color line of paints, although this was my first time using one of their flat paints. But no matter what I did: 30% TC thinner / 70% TC paint, 100% TC paint, 10% TC paint / 90% acetone, etc. the airbrush clogged instantly - as in not a speck of paint ever left the airbrush - as in before I turned on the air compressor, and from the looks of it - once I started looking for it - that the paint and the thinners kept separating like sand in water. And yes, I even tried lowering and raising the air pressure from my normal 30psi. No luck.

The paint is over a year old (bought it in January of 2015), but I hadn't used it until today. Then again, in recent days I've been using paint from 2014 without incident. So I don't know if it's age, a bad batch, the properties of the flat paint line, or karma. Any ideas as which it might be?

[ricnok]

How clean was the brush and I only ask because I have tried not breaking it down after a paint job so run lots of cleaner through but sometimes some residue gets in there and mucks stuff up. A quick tear down with a good cleaning usually fixes my issues. But with it separating, maybe the paint is suspect?

[AJ Kleipass]

A clog from dried paint was my first thought too, so I dumped the first batch of brown paint and did a full cleaning, but no joy. Did several more cleanings while trying to get the paint to work. Eventually, I even had it neatly spraying thinner and then added a bit of paint - BAM! instant clog.

[EMDX6043]

Did you try a different needle?

[Eccentric_Crank]

I've run into this as well.

Old (and sometimes new)paint often needs more thorough mixing, I have some over 40 years old, so I use a rock-tumbler(polisher) for several hours before spraying.
I put small containers in the tumbler jar with sponges to hold them in the middle while mixing.

Strain the paint! I also have a screen in the airbrush (wrap a spring from a pen with a scrap of panty-hose, slip over tube and tie at the top with wire).

Additionally I always store rattle-cans on their side or inverted so the pigment doesn't cake on the siphon tube.

Dan M.