How much paint

I know this is a open ended question but when airbrushing how much paint would you generally thin to say do a engine or shell of a 1/24 car.
I will be using Tamiya Acrylics thined to about 60% paint 40% thinner (also is this about right)
also do you mix this in a mixing jar or would you just thin the paint because of the small ammount in the airbrush its self (iwata Hp-C)
cheers

Thin in a mixing jar.

How much paint depends on what size the car is.

Thin in a mixing jar.

How much paint depends on what size the car is.
so say for the 1/24 F40 tamiya engine?

I don't build Ferrari's so I don't know how big that is exactly, but based on other models I have built with full engine details I can guess.

For that small a volume of paint, you can thin it in the color cup, you'll only need about 1/3 of the color cup of paint (thinned) to do several coats.

I've never played with an Iwata Hp-C, but my first question is: does it come with a color cup? If so, toss the bottle attachment!

I never thin paint by the bottle when spraying, and haven't sprayed with a bottle hanging from the airbrush in nearly 8 years. Every time I spray, no matter what type of paint I'm using or what is being painted, I put a bit of paint in the cup, and add thinner to it with an eyedropper. Also, I never thin to a ratio. Sure, 60/40 may be a good guess, but as I thin only for the single application of what I'm going to spray at one time, I adjust only for that time. That way, I don't get surprized by changes in ambient temp, humidity, air pressure, thinner evaporation, etc. Mix it up, test spray, adjust as needed, you're ready to go.

As a rule, thinner paint is better than thicker paint, especially with gloss. But you don't want it so thin that it will run. The only way you can tell how thin that is is by experince. You've got some learning and expirementing to do.

Can you get Model Master Acryl? Tamiya acrylic will work well too, but Acryl dries harder than Tamiya, so it's nice for painting bodies. Thinned with their brand of Acryl thinner, I find it to be a really nice medium, and Guards Red is a good match for Rosso Corsa. Prime the body with flat white acrylic or Tamiya's white primer from the spraycan.

Sooner or later, I'm going to have to get around to posting a How-to on how to make friends with your airbrush....

HP-C has a medium sized gravity fed cup. The only real answer to the question is use your own experience. If you haven't got any experience yet, then simple common sense and trial and error will determine what works for you. The is no right or wrong way.

Having said, that I usually thin and mix in the cup for smallish jobs. If bigger like a body or a lot of small parts to be painted the same colour, then I'll mix up a thinned batch in a jar so I can top up quickly and easilly.

For common colours like grey primer, black or white I keep a large jar of pre-thinned paint in my paint box. Saves loads of mucking about.

as you have siad the iwata is a gravity fed airbrush, i will do as you say and mix small ammounts in the airbrush cup and do larger ammounts in a mixxing jar for body pannels etc

Wilo,

I thin my paints mostly by eye. I tend to mix in a bottle, as my airbrush is a cheaper Badger 200 (it’s the artist, not the tools that make a model, that’s my excuse for having cheap kit and I’m sticking to it – LOL) and mix the paint using a broken bit of sprue. I thin to the consistency of milk, and when the paint drips freely of the sprue, I tend to count two drips, and then I know I’m getting somewhere good.

I tried to mix to a ratio once, and it wasn’t consistent enough. So now I use mostly eye. It is important to correctly reduce you paint, I’ve had strange results with paint that is too thick. Unless you are going for some type of effect, MPWR is correct. Thinner paint does tend to lay down better. But thinner paint does require additional coats, or so I’ve found.

One thing I think is worth mentioning. Tamiya Acrylic gloss finish paints are a constant pain for me. The finish is always kind of foggy and is very difficult to shine up. I moved over to de-canting tamiya laquers and thinning with a tiny bit of laquer thinner and I've had some results that have astounded me!! I highly recommend giving it a try!