I got a new Iwata HP-CH airbrush- until I get my Iwata compressor, I am using an old Paache compressor which makes a ton of noise.

I am trying to pre-shade a cockpit - I find that I don't have good paint coverage (I think I am thinning the Taymiya flat black acrylic too much) There seems to be quite a bit of air coming through - so much that I have to move the brush very quickly or be far away from the model - otherwise it pools - this is where I think the paint is thinned too much. The regulator says 40psi without the button on the airbrush depressed.

I tried to change the MAC valve but couln't get it right.

Any thoughts on what I am doing wrong?

I want better paint coverage and to be able to move the brush more slowly, closer to the model.

Hi Pauls, and welcome to Armorama.
I have the same AB as you. It sounds like you are thinning to much and your pressure is to high. With a gravity feed AB you'll find you will need less pressure then a bottom feed, 20 psi or less. Try backing off on the thinner and open your mac valve fully (until you need thin lines). If your paint is starting to "spurt" or there is to many "bumps"on the paint then your not thin enough. Your paint should dry with in seconds of landing on the model.
These ranges are fairly forgiving and I dont "measure " when I thin my paint and most of the time its good to go.


Good luck

Bruce

Bruce-

Thanks for the advice - I guess I just need to play around with it a lot more. It seems like a lot of trial and error. I think I will be able to control things a lot better when I get my Iwata Power Jet Pro compressor.

Thanks again.

Paul.

I recently had a similar issue when I thinned tamiya paint with MM Acryl cleaner. It didn't mix very well, and as the level of paint got low in my Iwata CR, the mixture became much thinner and started to pool on the surface of the model. This was at a pressure of approximately 25 psi. I'll go back to thinning Tamiya paints with alcohol or Tamiya thinner.


Martyn

What Slug said....
Also - I have read a number of posts that are complaining about Tamiya paint quality. Newer batches of Tamiya are not as easy to work with as they once were. So if you're able to - try another paint.

This may not sound right to anyone else, but I spray Tamiya unthinned through my Iwata and it does great with great one coat coverage and no runs at all.

I also spray Tamiya unthinned through my Iwata. I have only sprayed one model so far, but got good results. I am going to try Vallejo Model Air see what it is like.

Regards

A J

I actually prefer spraying tamiya over the MM Acryls at least. Though in defence of MM I have sprayed alot more with Tamiya. Hmm lets see... 2 models sprayed exclusively with Tamiya, 1/3 of a model with MM Acryl. I find the Tamiya is (usually) less sensitive to thinning. What I mean is a little too thin or a little too thick doesn't make a lot of difference. With the MM because it is already so thin... I ran into troubles pretty quickly with it too thin, and when I sprayed too thick it dried on the AB needle much sooner than Tamiya causing spattering.

I am sure once you get the mixture right MM is just fine. I wish Tamiya offered more colours, if they did it would be all I sprayed. I limit myself to these 2 brands as they are readily available everywhere locally.

But hey... I have airbrushed less than 3 models in total so I still have lots to learn.

Martyn

thanks for all the input - I started another topic about the compressor. This seems to be a mystery to me too.