Old paint stock.

I have never had problems with Tamiya paints clogging any airbrush that I have used. I presume that you are using Tamiya thinner with them? I do believe that Tamiya changed their paint formulation back in the late 80s. They used to hand brush much better back then, and I was told by the owner of a LHS back then that that was the case. Perhaps the new thinner is not as effective with the old paint formulation. If you are not using Tamiya thinner for your airbrushing, I suggest that you start there.

What's your thinning ratio? Tamiya acrylics like thinner.

I'd say that they're probably past their shelf life. 30 years--man, that's a long time to expect small pigments suspended in a thinner medium to stay workable. I'd save them for brushing only and invest in some new bottles.

I have problems spraying acrylics in extra fine tipped AB but Tamiya's paints seem to behave the best. As Karl said, they may be just too old. I suggest getting a fresh bottle and use Tamiya thinner and see what happens.

I've got some 30 year old Tamiya acrylics which are just fine. They seem to work ok with the current thinner formulation, but I also use denatured alcohol and Tamiya lacquer thinner depending on what I'm doing.

Thank you.  I got back into modelling in the early 80's and here I am with over 200 kits and boxes of GW figures to do.  These include several very big kits such as 1-35 Gustav Karl and four 1-350 battleships.  I thought I'd get through them when I retired but that was 8 years ago and I am still struggling to build any.  I bought the Tamiya paints in the early 80's as the shop was selling them off at a good discount.

I only started airbrushing recently and the Tamiya paints were / are fine for brushing.  I am thinking that the problem may be using partly used bottles for airbrushing.  No doubt some of the dried out paint from the neck fell into the paint, and it these particles that cause the problem. I thin with Tamiya thinners or maybe thinners with a little deionised water.  I aim for 50 : 50 paint to thinner.

I think I'll buy some new paints for the airbrush and keep some of the Tamiya ones for use with the old paint brush.

Thanks for the help.  I use 50 : 50.  The thinner is Tamiya's own and I may add a little deionised water.

Thank you.  I got back into modelling in the early 80's and here I am with over 200 kits and boxes of GW figures to do.   I thought I'd get through them when I retired but that was 8 years ago and I am still struggling to build any.  I bought the Tamiya paints in the early 80's as the shop was selling them off at a good discount.

 I am thinking that the problem may be using partly used bottles for airbrushing.  They may contain particles of dried out paint from the neck.

I think I'll buy some new paints for the airbrush and keep some of the Tamiya ones for use with the old paint brush.

Thank you for that.  I think I will invest in new paints and then just use the older ones for brush painting. I suspect part used bottles will be worse as they may contain dried paint fragments from the neck of the bottle.

Thank you.  I think I'll buy new paints, and if they work perfectly I'll just replace my paints.  I do use Tamiya thinner but I do have denatured alcohol and isopropyl alcohol.

Even tough the alcohol works in diluting the paint, I think it evaporates too quick and adds to tip drying. A flow improver and retarder help in slowing down the drying time and flow issue. That is why I rather use enamels. I can thin down my enamel and set the pressure down to 5-6 psi and shoot thin hairline patterns without any tip drying or skipping.

I rarely have tip-dry with Tamiya acrylics, perhaps because I run my paint very thin, anywhere between 2-4 parts thinner (or more)  to one part paint.  

50:50 is ok, but you'll get better results with more thinner.

Hi there thanks again. I will try more thinner.  I was thinking of buying Air Colour paints as they are already thinned but then I thought they might not be much use for brush painting so I think I'll buy Tamiya again.  I'll mark my old stock so that I don't get them mixed up.  I am probably not using my airbrush properly.  I use it to paint large sections of a model then use brushes for finer detail.  The airbrush is great for giving a uniform paint effect and for doing AFV camouflage.

Thanks.  I don't see me using alcohol a lot.  I tend to use thinner plus maybe some deionised water.  I don't like the smell of enamels when painting a large kit that won't fit in my spray booth.  I do wear a proper filtering face mask.  Trouble up here is it is very often to wet to work outside.