Those small model sized bottles of primer paint are soooo expensive aren't they. AND you normally need to also get their special brand of thinners, almost doubling the costs for a very small amount of paint in the end.
Well here is what fellow modeller Arthur Hayes does and what a great idea it is. He goes to Bunnings and picks up a can of Dulux Metalshield 300g Light Grey Etch Primer which retails for a grand sum of $11.95 and it is already thinned and ready to use. You can just use it from the can, but you get splotches and blobs and a heavy coat, as the can is really setup for 1:1 scale painting. But all is not lost.
Arthur says to just get a small disposable plastic drink cup and spray a bit of paint into it. From there you just pour this into your modellers airbrush and away you go! Nice and fine spray of a pretty good primer and its a nice light grey in colour - perfect. AND it is so much cheaper and one can is going to last you a long long long time.