POR-15 is not a rust converter, its a coating/encapsulator. If your going to let it set for months on end prior to paint consider using a phosphoric acid rust converter, "Ospho", navel jelly, etc...

these convert iron oxide(rust) into iron phosphate that coatable.

Then clean throughly, wire bruch, get all rust out then coat with POR-15. This stuff is as hard as a rock when set up, if this is inside a rocker panel or inside the vehicle thats probably a good location for this. If your talking about exterior panels with top coats of base & clear to go above this then generally its not recommended, its too slick & too hard. you can also consider an epoxy coating as long as its not in the sun (no UV) instead of POR-15.

If you dont do something like this method first, rust will reappear.

http://www.ospho.com/

Here is an excellent auto body site to search thru as well.

http://www.autobody101.com/forums/

Interesting reading....I might look into these rust convertors - as the price of sandblasting a whole car runs up over $1000 here! I'm looking for a $200 solution to removing rust from a whole car then painting it...

if you dont want it to ever come back it will need to be sand blasted

Your probably right rb20 - I don't mind if it comes back in 5-10 yrs....can I get away with 5 years without reoccuring rust without sandblasting?

This is the boy's Torana I thinking of using some sort of brush on rust convertor/enscapultor the paint brightside over the top of it - a $200 solution was the plan.

Or am i dreaming to go that cheap