Basically, you paint an undercoat on, usually black, then a base coat of "rust" colour. Then you spray the model with hairspray and sprinkle on salt, both the larger flaked "Maldon" type and normal table salt granules. The salt is placed wherever you want the rust to show through and the tiny salt crystals mean you can get a really random arrangement. Then you then paint on your topcoat. Wait for it to dry and then scrub away the salt with an old toothbrush.
There's a bunch of good guides of how to do it on the Internet (certainly better than mine) but this one is a good start: How to do it right
I picked up an Airfix Mk 1 Male Tank from Hobbycraft recently, with a mind to turn it into some sort of Punkanaught Battlewagon of some kind. It's the inspiration for no end of GW vehicles, the Land Raider and the Chimera and the Leman Russ can all draw their origins back to this design, and with a few additions from the bits box I had a suitably scifi vehicle.
I then made three mistakes. Firstly, I over sprayed the hairspray again twice, sealing the salt into a nice, hard lacquered layer. Secondly, instead of gently airbrushing on the main colour I stippled on GW foundation paints. In hindsight, I should have remembered that the GW foundation paints will and do cover ANYTHING in a layer of paint that is pretty much impenetrable by any device known to man. Thirdly, I chose a red and orange camo scheme. I'm thinking that the GW meme must just have overtaken me. Why I didn't go for a nice, neutral green, or grey or tan scheme is a mystery to me.
Once the paint had dried (or set, might be a more accurate description) I started in with a toothbrush to scrape off the salt. I started off lightly and gradually increased the pressure and nothing happened.
I then started in with my Dremel.
Clearly all reason had left me at this point as I began with a soft polishing attachment and moved on from there through the various nylon brushes until I ended up with a steel wire brush attachment. The smell of melting plastic brought me back to my senses and I put the power tools away.
The hairspray, salt and GW Foundation paint mix had set into a sort of lurid red and orange Chobham armour coating that I was beginning to think might actually be useful to the MOD in some way.
In a last ditch attempt at salvaging something before I dumped it all in a big pot of Dettol Pine disinfectant that I use as a paint stripper for plastic and resin kits, I washed it under the tap and had another go with the toothbrush. The water seemed to work, and with some vigorous brushing the softened paint gave and the salt below was exposed. I let it dry, touched up the bits I had ground away by mistake and added the metallic bits and here are the final results:
|Note the wrecked detail on the windows and hatches|
|Added Old Crow gatling on the front and GZG guns in the sponsons|
The end result is OK, certainly fine for gaming purposes, but it's not what I wanted. In retrospect, the Red and Orange camo was a terrible idea with a brown rust base. I should have gone for more of a contrast, like the tan colours in the example above. I also had to paint over all the white plastic exposed by my manic Dremel attack. Still, you have to admit that it certainly looks battered and weathered.
I left the "tail" steering unit off and when I looked at it it reminded me of a gun carriage. I had another dig around in the bits box and assembled this from the "tail", some styrene tube, spare AA gun barrels from an Old Crow tank, a couple of Old Crow 6mm missile turrets and some ammo clips from a 1/50th VOTOM kit:
It also got the salt and hairspray treatment, but seems to have fared a little better. I always loved the original mechanic for Thudd Guns in WH:40K where you placed 4 blast templates down, one after the other, but each one deviated from the edge of the last one. You could end up with a long chain, or with them snaking back on themselves, or a totally random mess, and this was created in honour of that.
I also thought I'd have a go with some MIG pigments that I picked up at a model show last year. I used them very sparingly to tint some ground clutter that i was making a while ago, and chucked them back in a box and forgot them. I usually use Tamiya pigments in the little compacts (what AGG calls my geek makeup) to very satisfying effect. The Mig pigments went EVERYWHERE though. I got a blob on one of my fingers and didn't notice and now have orange rust stained figerprints all over my camera, the lightbox, my clothes the ketboard and all the minis handled until I noticed it - there's agreat big blob on one of the barrels of the Punkanaught, I just noticed . Clearly more practice is required.