Some questions from person new to airbrushing.

Here's the deal: mix and test shoot, then you will know for yourself. I say that for several reasons I don't need to get into. Don't take that wrong but from it you can get your aswers and also questions.

As to Andy and Donn, they didn't reinvent any wheels, some of us been shooting enamels this way and also the way you mention maybe doing for 4-5-6 decades. Course in that time some thinners have changed and also some/most kit plastics too. So test .

Testing is always best.  In general I have had success mixing MM enamels and laquer thinner 1:1.  And laquer thinner is my goto for cleaning the AB.  I have the same Paasche H.

The only thing I'd be concerned about when choosing one type of thinner or another for MM enamels is whether or not you're planning on returning the leftover paint to the jar.  If you use Testor's own enamel thinner to thin it, you can return it to the jar.  If you use lacquer thinner, returning the leftover paint to the jar may or may not severely shorten the shelf-life of the paint.  So, try both yourself and see which results you like better, and just remember not to return the laquer-thinner-mixed paint to the original jar.

For the Testor's clearcoat paints, those are lacquer paints, so use lacquer thinner.  You can use lacquer thinners in enamels and even some acrylics, but in general, you can't use the thinners for those other paints in lacquers.

I can't really comment on airbrushing techniques with the Paasche H because most of those YouTube videos about airbrushing make me cringe with how much paint they're putting down in a pass.  My method is just different and works well for me (have a 35-year-old Paasche H I bought when I was 15, and its really the only airbrush for me), but it may not necessarily work well for others.  I'll echo what OMG said, and just say you have to learn by experimentation.  YouTube videos are good for ideas, but take them with a grain of salt and try them while knowing that you may find a way that works better for you.  With most of this, there's really no right way to do things.  Plenty of wrong ways, but you'll figure out what those are...and isopropyl alcohol and a cheap electric toothbrush are a great way to safely strip the paint if you try something new and it ends in disaster.

People here recommend testing things out. Test spray on plastic picnic spoons or pieces of runner from the model kit? I would think Testors already did that chemical-compatibility testing in their science lab on "the 5th floor" to prove their products. Testors products are chiefly for the plastic model hobby. Yes, I do want to conserve paints and paint mixtures by storing them in jars after shooting sessions. Lacquer thinner mixed in Testors top-coat clears should not harm the plastic because there will be cured enamel base coats already covering the plastic parts. 

I found this Testors enamel thinner in 8-oz. cans, listed on amazon.com, and it's a much better deal than the small bottles of the stuff. 

It comes down to the term penny wise but dollar foolish. It's ok in my mind to just buy an extra bottle of paint now and then to practice with vs wrecking the paint job or plastic on a $35 model.

Additionally mix what you need using pipettes. You can get a bag full of 100 pipettes from Amazon for $4-$6. And I clean those several times before giving up on one and tossing it out.

Decanted Rustoleum Painters Touch 2x paint with a little lacquer thinner added gives up pretty much the same result as Testors or Model Master enamels when shot through the Paasche H at 32 psi or so. $4.99 for 12 oz cans, test your heart out lol ! I'm doing a 1/16 57 T Bird in that paint, that's my confidence level in it ( they have a close match to the light sea mist green).

I'm slow to say Kleen Strip hardware store lacquer thinner is the end all to a good finish. Yes LT works in enamel just fine but LT here in my state may not be the same in yours and certainly not in California where regulations differ. Here in Ma I still sense that KS LT is decent stuff but in California the same brand is almost 100% acetone. It's going to behave differently. Thus it's to your personal advantage to just "Test". Amen

I'm in RED-state Oklahoma. Not very environmental regs here. I already have a bag of cheap pipettes. I still need some mixing cups, some lacquer thinner and some Testors enamel thinner before I start TRAINING with my new Paasche on disposable plastic items before committing it to $35+ model kits. I also need to buy some cork gasket material to make seals for my new set of Paasche 1-oz. jar lids. 

JonBailey

People here recommend testing things out. Test spray on plastic picnic spoons or pieces of runner from the model kit? I would think Testors already did that chemical-compatibility testing in their science lab on "the 5th floor" to prove their products. Testors products are chiefly for the plastic model hobby. Yes, I do want to conserve paints and paint mixtures by storing them in jars after shooting sessions. Lacquer thinner mixed in Testors top-coat clears should not harm the plastic because there will be cured enamel base coats already covering the plastic parts. 

I found this Testors enamel thinner in 8-oz. cans, listed on amazon.com, and it's a much better deal than the small bottles of the stuff. 

 

I have found that Crown Lacquer Thinner from Lowes to be effective in thinning ModelMaster as well as other enamels (Humbrol, Colourcoats, etc) for airbrushing.   Its my cleanup spray for lacquers too, Clearcoat, Dullcoat, AlClad, etc)    I buy it in the gallon tin and decant what I need into useable bench-sized containers.  It saves big bux over buying the paint's own material at a greater cost per ounce basis.  Parks is hot enough to do the thinning job but not so hot as to craze polystyrene under most typical airbrush applications.   

Your $10.09 tin of Testors thinner runs you about a buck and a quarter per ounce.   Crown in the 32 oz tin runs you about 30 cents per ounce.   

Of course, always experiment with a new material or procedure before committing on your current masterpiece.

Resist the urge to pre-thin a lot of paint for your potential painting needs next week, or next month, or later.   Once you mix in a thinner a chemical change begins which will result in that 'special mix bottle' you set aside being reduced to an unusable blob.  Sounds counterintuitive but peruse back through multiple years of threads to see other's results of doing similar.

Another thinner that works awesome in enamels is to mix about 50/50 Odorless Mineral Spirits and hardware store Paint thinner together, then thin your paint about 5 parts paint to 4 parts the thinner blend. Flows real nice, the paint thinner alone will flow great too but it can cause a fisheye type of reaction that isn't there by adding the OMS. OMS by itself for me doesn't level the paint enough and dries the dullest of all I've mentioned in this thread. Course again I suppose this may be different in other states too. This is all Kleen Strip products I'm mentioning, least thats what I use. But LT alone will do fine.I have found KS LT not to be too agressive on plastic when mixed in enamel paint. It's not super hot thinner like some automotive thinners. In fact my latest batch doesn't clean the airbrush like the automotive stuff does. It cleans ok but you almost don't even have to wipe down the auto stuff, it's quite a bit stronger and smells the part too.

You can get 1 oz. jar cork gaskets from Paasche if you want to.

https://www.paascheairbrush.com/5-G

For mixing cups, I just use the little bathroom-size Dixie cups.  They stand up just fine to any paint/solvent mixture, except for ammonia-based paint like the Model Master Acryls...those require a plastic mixing cup.

Eaglecash867 above says mixes of Testors enamels and Testors enamel thinners should keep in sealed jars. 

JonBailey

Eaglecash867 above says mixes of Testors enamels and Testors enamel thinners should keep in sealed jars. 

 

I couldn't really say, I haven't used Testor thinner since around 1978 or so. But I have Testors MM enamel in jars with that combo thinner I mentioned above, so far been about two years. Still good ( I just checked it).

JonBailey

Eaglecash867 above says mixes of Testors enamels and Testors enamel thinners should keep in sealed jars. 

 

That's not necessarily a hard rule though, just saying that I know that to be safe.  Looks like OMGs thinner mix has proven to be safe too.