Is it okay to thin Tamiya or Model Master acrylic paints with white spirits (paint thinner?) Will I run into any problems if I am to airbrush on another layer of paint, as in will I run the rick of the white spirits stripping the previous coat of paint?

You can NOT thin acrylics with white spirit since acrylics are water based. Use rubbing alcohol, Isopropanol, destilled water or thinner supplied by Tamiya or Model Master. Acrylics and white spirit will not mix and you will only create a real mess on your model. White spirit will not have an effect on dried acrylic paint, so mixed with oil or enamels it is good for washes etc.

Erik

carefull with model master... i don't know if it thins with the same stuff as the tamiya... like erik said, it won't work with acrylics....

Frank

Thanks. That's pretty much what I thought. Luckily I have a water cooler with plenty of distilled water on hand at my house.

I tend to use isopropal alchol to thin down acrylic paints. It works a treat and it dries alot quicker than using water.

Windex also works great.

As said a big No No, I have heard of people thinning acrylic with Cellulose thinner, but me I stick to water, Tamiya thinner or Isopropanol.
I would imagine that if thinned with white spirits it would clump into a really sticky mess........yuk

John

Well, I got so tempted to see exactly how bad it would be to mix acrylic paints and white spirits that I mixed up a small batch of it. I tested a ratio of 3:2 paint to thinner, the paint being Tamiya XF-60 Dark Yellow. Amazingly, it actually mixed perfectly after about 10 seconds of shaking. I was so impressed that I sprayed a tiny bit of it out of my airbrush (which I use for spraying oil paints) and it went on perfectly to a scrap piece of plastic. Furthermore, it hardened approximately 10 seconds after it went onto the plastic, leaving behind a perfectly smooth coat of Dark Yellow. I took apart my airbrush to clean it, and there was no build up. I still have that paint sitting in a jar, and it has not yet seperated into a mess of pigments on one half and thinner on the other.

I don't want to really try this again, but I thought it was a bit interesting to see. There you have it, so you don't have to try it.

Nah! I think you should try this again.

Okay, I took you up on that because I'm convinced that if done properly, it won't become a God-awful mess, just a pointless thing to do.

I mixed some Model Master Schwarzgrau RLM 66 (4779) with paint thinner in a 3:2 paint to thinner ratio. I was so confident that nothing bad would happen that I sprayed it on a PzKpfw IV Ausf. F1 on top of my base coat. It worked fine, and the paint dried almost as soon as it made contact with the model. After that, I thinned some more Schwarzgrau, this time with distilled water, and sprated a second coat. It went on smooth, leaving a perfect second coat on top of a perfect first coat. I did my detailing, weathering, spreayed on some semi-gloss, some more weathering, a wash, and the model was done. It looks perfect.