minor rust repair "order of works"

[Norfolkandchance]

One of our cars has rusty door bottoms, apparently cased by water running past the door seals and collecting in the bottom of the door. The rust is worst on the inside but has come through to the outside so is visible in several spots. The actual bottom, where the steel folds, is fine, the bubbling is 8-10mm above. Its been visible on the outside for at least 4 years, without really getting worse. Possibly because the car now spends most of its life inside a garage.

So I've got all the stuff but wanted to check on the order and if I've missed anything. Aim is to make the car look reasonably smart from the outside for a few years, not fool anyone in a close inspection. its a long time since i did anything similar so just wanted to check. Car is black, if that is important.

Proposed order:

Wash car
Remove any loose flakes from inside door with wire brush.
Paint on rust converter inside door. Allow to work. (I have one that has done well in tests)
Paint on two part underseal type gunk (This one also did well in tests) to inside doors, with aim of stopping water collecting in bottom of doors, or at least prevent it getting through to the metal.
Use drill mounted sander to rub down bubbling on outside of door. Feather edges.
Mask off areas to be painted. Should I just do the rusty areas or a straight line along the bottom inch of the door?
Use high build primer spray on rubbed-down area, possibly filler if required
Sand down, clean (what's best product to remove any lose dust?)
Base coats in colour as per instructions on spray can.
Clear lacquer as per instructions
Possibly rub down lacquer, if required, but I expect it will be good enough.

The alternative would be to do the outside first, in case the rust is worse than it looks and I break through to the inside?

Thanks

Use

[Belle427]

Id use something oily like dinitrol in the doors, can be topped up regularly.
Its better to try and clean back to bare metal as best as possible before using any converter type product. (most dont work) Thats if you can get to it.
There are a lot of good products on Rustbusters website.

[sugerbear]

I have used Bilt Hamber Deoxy C and Hydrate 80 after recommendations on here. Seems to be doing the trick.

[Norfolkandchance]

Thanks for replies. The anti-rust stuff I've already purchased is from Rustbuster.

[steveo3002]

if its bubbles then there will be holes once cleaned up..how do you plan to fill those

is it the sort of car you could find cleaner doors from a scrap yard?