I am having a bit of trouble properly thinning Mr. Color paints. This is my first time using them.

I started by initially using a direct 5:1 mixture of Mr Color thinner to paint. This mixture sprays well through the brush, but it is extremely thin and has trouble staying in areas of high detail.

I then added more paint to the mixture to about a 3:1-2:1 mixture of thinner to paint, however this stopped the paint from flowing through the nozzle even with it cranked wide open.

I went back to the 5:1 mixture. I have applied several coats, which has helped overall, but it still refuses to collect around fine details.

Any thoughts/advice?

A better way to thin paint is to check the consistency. It generally sprays best when it is about the consistency of milk (not skim). Ratios can vary due to temperature, humidity, paint brand, and color (different sizes and densities of pigments for different colors).
A couple of other things to consider:
Paint can run off if the part is too warm or too cold, as the paint won't adhere properly. The same thing can happen if the paint is too cold, too.
Too much paint tends to make it pool and run off of raised details and collect in depressed details. This is an indication that you are applying it too heavily, and you should try thinner coats.
Many gloss colors don't cover as well as flats and will tend to pool and run off if applied too heavily. A flat coat of the same color is usually more dense and has better "tooth" and will act as a good primer coat for gloss coats.
Hope this helps a little.
Norm Samuelson

Thanks Norm.

I paint in 1/1 scale with different paints and a large airgun. This is my first foray into smaller airbrush territory. I'm not having any problems with applying it too thick. However the paint is collecting on large flat surfaces, whether they are vertical or horizontal, but not around raised detail. The consistency of the paint is a little thinner than milk. I have trouble with it clogging otherwise.

Also of note, I have primed the areas being painted with Mr Surfacer 1200, and the parts have been washed in dishwashing detergent and water prior to assembly.

What brand thinner are you using to thin them with?

Gunze across the line for thinner, paint, and primer.

Jeremy, sorry if my comments were kind of basic, never quite sure of the experience when there is a question regarding paint. My next question would also be what thinner are you using? I'm pretty serious about using manufacturers thinner with their paint, as I've seen and had enough problems with trying to mix-n-match between brands.

Oops, just got your reply on paint & thinner. My next comment would be to contact the manufacturer and see if there are any recalls or bad batches of paint that they are aware of. It does happen, even to the big brands. Sorry that I can't help much more than this, as it sounds like you are doing the right things.

I have sprayed Gunze a few times (normally I use a different brand), but a 5-1 thinning ratio seems to be too much for me, and even 3-1 is rather thin in my experience.

I guess your problem comes from high pressure. What pressure do you use? With a gravity feed AB 1 - 1,5 bar is absolutely enough for Gunze paint (maybe even less for detail work), with vacuum feed max. 2 bar (that is about 30Psi). If the pressure is too high, the paint blows itself off from the surface. Also, when exiting the nozzle it cools down suddenly and dries there - this may cause the clogging.

Try a session at about 20 Psi and see if it works that way. Hope it helps.

Norm: Thanks, and I hope so. If I can't figure this out then I may indeed end up contacting the manufacturer.

Gabor: For whatever reason the airbrush becomes clogged if it even looks like I am approaching a 2:1 ratio of thinner to paint. I am using a vacuum/siphon feed Paasche H airbrush, and I have had the pressure set at about 12psi. Therein may lie my problem, I will try cranking up the pressure to about 20psi and see if that helps out.

Hi Jeremy,

Definitely try raising your pressure. 12 PSI is too low for the Paasche H to "draw" paint unless it's super-thinned as yours is at the moment..

20 PSI is a good place to start - with a "H", I don't think you would really be able to push it below about 16.

Phil: Thanks for the info! I'm used to working with gravity feed. I'll try again tomorrow if the weather is permitting.

Well it seems you have a pressure problem... if not too much it is too low, I was at least partially right

Let us know how it turned out.

Hey Jeremy , oh ya usin a suction feed they suck you have to run the pressure higher to draw the paint up as others have said.
the big thing i hate is because of that you cant really fine tune the airbrush like you can with gravity fed guns, i had a delta suction gun which is a nice gun but i bit the bulet and got 2 iwata gravity feed guns, one i use for general work and the really good one is brilliant for fine detail work.
with them i can run the compressor down as low as 5psi and nearly shut the paint off with the adjustment it has, but as a general rule i run about 10-15 psi and just shut the guns air valve down as i want.
with the gun your using i'd start around 15-20 psi and slowly work back if you can till it starts to splatter then jsut raise it a little till it smooths out.

some suction feed gubs ive seen do have adjustments on them so you can run the base pressure higher and just turn the gun itself down but there generally like the real expensive ones LOL as with anything i guess ya get what pays for.

with the gunze paints what are they acryilic or enamel? i use the acryilic ones of theres and tin it with meths works great, you get super fine mist coats because it dries fast, depending on the weather if its hot just use plane ol water like if its above 25deg C but if its cooler meths is good and wont hurt anything in the gun either specially if you have to have paint in it for any length of time as i often do.
hope i aint being to technical i dont even think about it anymore as I spray paint for a living and its just second nature.
im not sure what is best for enamel version but i'd probably use turps or something similar, not sure what you guys have in the US.
hope this of some help mate.
cheers,
Graham

Hi Graham,

Jeremy is good to go with what he's using as a thinner.

Gunze's Mr Color range are described as "solvent based acrylics". For all intents and purposes, they are treated as a lacquer and work best with Gunze's proprietary "lacquer" (Mr Color) thinner (I haven't tried Tamiya's lacquer thinner yet, but I suspect that it will work). It's neither an "aqueous" acrylic like Gunze's "Aqueous Hobby Color line nor is it an enamel. Neither water, metho, turps (as we know it) or mineral spirits are suitable.

Graham: Those sound like nice brushes, but are more than likely unnecessary for what I am doing. The Paasche H is a good general use brush, and I have seen a lot of very nice models, paintings, and other custom paintwork done with them.

Phil: I haven't looked much into the technical aspects of the paint, but what you are saying makes sense. I use a similar type of paint for automotive applications, so I should probably be exercising a bit more confidence with the Gunze paints.

I haven't had a chance to try painting again today, will try tomorrow morning and let you guys know how it goes.

Hiya Phil oh i didnt know they made that solvent based stuff , yeh your right lacquer thinner is the go , ive only seen and use the water based stuff as i work with that smelly crap all day its nice to not have a stink when i m doing models lol.
hope ya get it sortted Jeremy.
cheers,
Graham

Yes Tamiya thinner works with Gunze Mr Color (I use it regularly because Tamiya thinner is easier to get and also cheaper than Gunze). The two materials are not the same but Tamiya still works.

Hey guys, just wanted update you all on situation:

I cranked the air pressure up to 32psi

Mixed the paint to somewhere between a 1:1-1:2 ratio of Mr Leveling Thinner to Mr Color

And.... it worked out beautifully!! A perfect misting coverage that lay down smooth and evenly and dried very quickly leaving a wonderful satin finish. Much thanks again guys