On the very edge of my driver door, I have chip that has now turned to rust.

How can i remove or prevent it from spreading

 

i dont wanna give bad advice but if i were in that position i'd sand and use some touch up paint. i did this for my mom's rav4 paint chips and they stopped getting bigger. wanabe probably has a better solution that would give better results, i'm just a noob and can't compare to his greatness >.<

 

you can also try naval jelly... its an acid and will eat stuff, so you gotta be careful- but it is used as a rust remover (usually on non-painted surfaces- but if you will be repainting, it would be on my list of steps to take)
more info is at:

https://www.s2ki.com/forums/index.php?showtopic=426977

as to the sanding... great info here:

https://www.s2ki.com/forums/index.php?act=S...=0#entry4696450

see- i dont know everything- but hey, i know where the links are!!!

 

On my offroad truck I used a grinder and grinded it off and then painted some stuff called POR on it. It is some awesome stuff and will keep it from spreading. You could go and find it and try sanding it down and use it before you paint it.

-Ian