Getting rid of rust properly :

Many people think removing or treating rust is as simple as slapping on a bit of paint, others have the right Ideas but use the wrong products or just use them incorrectly, here I can help with a simple guide to rust removal.

First off the best way to get rid of rust is to cut it out completely, sadly many people will pay good money to a garage to do this job and often it is done to a poor standard because you won’t notice the difference until it’s too late. The important thing to remember when welding in a new panel is that you protect that new panel as early as possible on both sides, sometimes this isn’t easy but you can now get chemicals that you can paint on the inside of a panel before it is welded in place (look for Zinc Weld proof paint) and there is always spray wax/ waxoyl that can be sprayed into cavities to repel moisture. It all saves you money in the long run.

When replacing a panel is not possible or not financially viable then there are a few options open providing that no holes have developed. First use a grinder to skim off the top layer of metal, be sure you don’t go too far as the metal is only thin and you don’t want to affect it’s strength or to break through you may be able to get rid of all visible rust with this method, but if the panel still looks a little pitted (seen as very small dents) then a drill or grinder mounted wire brush will remove as much of the remaining surface rust as possible (be sure to protect yourself especially with the latter as the wire and rust particles can fly at you at quite some speed and have been known to go through several layers of clothing). A rust killer such as Vactan is a good solution for applying sparingly to any areas that may still have visible or invisible rust. Vactan is a professional use product and much better than those sold in you local DIY store, Red Oxide is often mentioned in the car world as a good rust killer, but it is not and simply trades on the good name it had in older times when it contained Lead, it were these old and no longer acceptable chemicals that gave it it’s rust killing properties.

Once the rust killer has dried you need to cover the bare metal as soon as possible, first it needs to be cleaned with panel wipe (White spirit and other oil based cleaners are not suitable for this) and the panel wipe should then be wiped off thoroughly and then filler can be applied to get the area smooth and level again, then the panel should be painted.
It is not advisable to use the vehicle when only the filler or primers are applied as these are pourus so will absorb moisture and lead to further rusting underneath your new paint, a suitable lacquer should be used before taking the vehicle out into the elements, although wet sanding is fine as long as the panel is dried and cleaned, instead of being left damp for any period of time.