Old paint? Bad paint? or Poor paint

[davevw]

Hey guys, 

 

So I have a question in regards to bad paint. I keep ending up with lots of sediment when I try to airbrush model master acrylic paint and I'm not sure why. I've had this paint for a while after a move, about a year in storage, is this the reason? is model master acrylic just a poor manufacturer? or is it possible its a bad batch? I've only had this problem w/ tamiya paints once or twice, but I was able to use a filter for those. My filter won't work for this one. what do you guys do in this situation. I can't even fight through it as it clogs so terribly. 

 

Thanks, Dave. 

Edited November 5, 2016 by davevw

[nspreitler]

I had  at least 20 bottles of Polly Scale go bad in a move, probably from heat.  It did almost exactly what you are describing.

 

Model Master isn't a poor manufacturer but with what you are describing that bottle is bad. 

[k5ikl]

Yeah, it's bad.  I have the same problem with my MM enamels when they have sit to long and

haven't been used in awhile.  All of my paints are inside at room temp.

 

Cheers,

Jerry

[86Sabreboy1]

Was your storage temperature controlled or no? If you experience cold winters and your paint experienced near freezing or freezing temperatures then yes it's gone bad. The cold will "shock" the paint, especially during fall and or spring when nights are cold and the day time is warmer. Water based Acrylic paint is very susceptible to temperature shock. I've experienced similar with acrylic paint that went on multiple flights with me. The hold on commercial airliners (with exception to compartments that accommodate animals) is usually only 10ish degrees north of freezing during flight.

[davevw]

So the paint was in an uncontrolled environment, but...... Now I bought more MM paint, brand new, assured by the LHS. Now I tried spraying it and the same thing happened. I am so frustrated, I can't get this to spray. I have never had this before. It clogs up the airbrush like glue. 

[randypandy831]

What thinner are you using? Not saying you're using the wrong thinner but I've heard of some folks using the wrong thinner causing it to gum up,blob, ext.

Edited November 17, 2016 by randypandy831

[86Sabreboy1]

On 11/17/2016 at 2:56 PM, davevw said:

So the paint was in an uncontrolled environment, but...... Now I bought more MM paint, brand new, assured by the LHS. Now I tried spraying it and the same thing happened. I am so frustrated, I can't get this to spray. I have never had this before. It clogs up the airbrush like glue. 

I'd question how you clean your airbrush. Are you doing a full disassembly removing the fluid nozzle? If you've only "flushed" the airbrush I'd suspect there's still old paint in the airbrush. As for thinning of Testors Acrylic there are only three choices to pick from, Distilled water, Testors Airbrush thinner (cool formula) or Testors Airbrush Thinner (same formula as Airbrush thinner but hotter). Anything else will likely cause crappy performance, especially Isopropyl alcohol.

[Mr Matt Foley]

Definitely a thinner issue. If you are using an acrylic formula, you will never go wrong with distilled water. Personally I do not like Testors brand paints of any type due to the poor pigments used (not very fine). When using Tamiya, I always use the Tamiya X-20 Lacquer thinner, When using Gunze, I use the Mr. Thinner products. Recently, I have had very good luck shooting AK Interactive using a couple drops of Tamiya X-20 and I have had great luck thinning Xtracrylic with distilled water, same for Vallejo.