Frame prep

[1979jimmy350]

What is the best way to prep a rusty frame for paint. What would be the best way to remove the rust and prevent it from eating through the new paint?

 

[heavy4x4]

Absolute best: Acid dip /forums/images/graemlins/yikes.gif
Pretty good: Sandblast /forums/images/graemlins/woot.gif
Acceptable: Wire brush and elbow grease /forums/images/graemlins/waytogo.gif

There are a lot of products out there for rusty metal. I believe POR15 is meant to be used on a rusted surface. If the paint you use (be it tractor implement paint, or whatever) says to have a rust free surface, scrape off all the loose rust, wire-brush it, and then use a rust-converting product (naval jelly rust dissolver works well) before you paint.