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GRRRRimy Black

1.9K views 6 replies 5 participants last post by  Jack - Freshwater Models  
#1 ·
I wanted to learn to airbrush so I sprung for a Grex and invested some time experimenting. I am very pleased with the Grex and even more pleased with the results it creates - with one exception. For some reason, it will shoot Grimy Black for about 4-5 seconds before it clogs and stops spraying consistently. I am using acrylic Polly Scale. While this may not be the ideal airbrush paint, I have learned how to thin it and can get it to shoot GREAT - except for Grimy Black. It is readily available at the local hobby store in every color I need. I tried Badger MODELflex and get the same results. What I am primarily looking to do is to apply a Grimy Black overspray.

What's the secret?
 
#4 ·
What thinning ratio are you using for Polly Scale? I like to use 80% paint to 20% thinner (distilled water)


I personally do not like to use Polly Scale for airbrushing unless I absolutely have to for an available color. I much prefer to use Floquil when airbrushing. To me there is just too much surface area when painting G gauge items with a quick drying paint like Polly Scale which can easily clog an airbrush.


Another thing you might want to look into is a paint screen filter, like this one:


Airbrush Screen Filter
 
#7 ·
Thanks, I just looked up Grex air brushes. They look like a quality product!

BUT, they are all internal mix.

I use both an internal mix and an external mix pasche depending on the job at hand. The brand doesn't matter much as the principle is the same. I find the external mix brush is better for laying down a solid coat of paint and the internal mix better for very fine weathering. In either case grimy black might warrant using a medium or large nozzle if it has a large size of pigmant.

I generally try to use the external mix brush as much as possible since it is easier to clean and a clean brush works better. I find this especailly true with various acrylic based paints which I thin with alcohol since they tend to gum up the works pretty quickly.

Jack