Most peoples vehicles will be WAY too shiny for this trick, but it might be useful to someone.

Unusually for a Taiwan car, my (1986) Daihatsu Skywing has almost Scottish levels of corrosion, probably because a previous owner was a surfer

I sprayed the underside with a diesel/oil mix to slow it down some. For the topsides, I've cleaned up the rust patches with crumpled aluminium foil as an abrasive pad, used wet with sunflower oil. Rust, old paint/primer, and aluminium flakes form a protective paste which can look rather like a metallic primer. If you clean it up first, the aluminium content of the paste is higher and it looks more like primer.

Ordinary sunflower oil takes a long time to set, and I don’t know if it would ever be a suitable base for a “proper” paint job, since I’m not interested in cosmetics.

Boiled linseed oil would set quicker, or one could use superglue, as described above. A pre-clean with foil and phosphoric acid (Coca Cola?) might also be worthwhile.

I think one might be able to get the veg oil to "set" quicker by adding an oxidising agent (eg hydrogen peroxide or potassium permangenate) but I havn't tried that either, not having needed to.

Exciting pictures. See pseudo-paint dry!

Large rust-patch on the tailgate

[img]farm5.static.flickr.com/4064/4649059025_801b4ff788...g[/img]

Deep pitting next to the window seal

[img]farm5.static.flickr.com/4068/4649677666_221b42bbd9...g[/img]

Should have done a before and after, but if you don't know what a rusty car looks like, you probably don't need to.

I should mention that on some of the rust patches (I think maybe the pitting one shown above, but I'm not sure now) I used a short section of aluminium tubing (bit of old TV aerial) packed with foil, in a power-drill chuck, as an initial clean-up tool, followed by the oil-foil.

You might also try an aluminium roofing nail in a drill or Dremel. I'm thinking the chuck would grip the nail at the pointy end and the head form a little grinding disk. I can't try that here because I don't know where to get them, but IIRC B+Q (and probably builders merchants) had them loose in the UK.

Beer cans are usually made of aluminium. Combined with the right size rawl-bolt, they're good for power-abrading larger areas of rust.

You can, for example, roll some of the can tightly to form a rod using the steel tube of the rawl-bolt as a holder. Since that has splits, you might be able to make a flap-wheel, though I havn't tried that yet.

You can use the bolt (with bigger washers) through the centre of the cut off base of the can, which forms a cup shaped abrader. ( This fatigues quickly and comes loose, so its especially important to protect your hands, arm and face with this configuration, though eye protection is crucial with any configuration.)

You can flatten the whole can, punch a hole through the middle, and mount it on the bolt (with a few others, depending how much thread you've got) as a grinding disk.

Zinc or aluminium paint usually specifies sand blasted (or very thoroughly wheel abraded) steel to ensure electrical contact and cathodic protection, which isn't very practical for most of us. The rationale with this cheapo punk version is that, by using the the aluminium itself as an abrasive, it is forced into intimate microcopic contact with the steel where its scraped off on it. Its to some extent self-regulating, since rusty metal is pitted, and hence rougher, and so tends to acquire more aluminium. It wont get deep into pits like sandblasting, but its not bad.