Okay maybe a dumb question, but I won't know unless I ask :D

I'll start off by saying that I'm a complete novice at bodywork, but learning as I go... So I'm removing the rust from behind the door hinges on the pillars, I wire wheeled it back to bare metal, but I don't know what these darker spots here are???

They're not brown like rust, they appear to be dark from most angles, so I don't think it's just the lighting? Is this spot ready enough for primer?

 

lol naww its just spots where the wire didnt get to.
if your worried abuout it. just sand blast it

 

its basically pitted areas where the rust ate at the metal. but u have removed all the rust... u can epoxy primer it

 

/\ what these guys said.

some light spot blasting can do wonders for removing rust that the wire wheel couldn't reach.

just make sure that you cover your threaded holes before you prime it. i've forgotten many times while in a rush and it makes for a hell of a time getting the bolts back in if you don't have a tap and die set handy.

 

awesome. cheers for the help guys. After I've primed it, would you recommend putting some kind of sealant between the pillar & hinge to stop any water from getting back in there?

 

if u use a primer surfacer they r porus (spelling?) anywhooooo, an epoxy sealer will prevent it from rusting...

o ya pores will allow water to penetrate and start rusting again.

 

if you use a high quality epoxy primer/surfacer or give it a good coat of quality metal-etch primer underneath regular 2 part primer surfacer, then seal it and base/clear you shouldn't have any problems for a long time. the striker plate can go right back on and you'll be fine, as long as you don't hack it all up in the process of putting it back on.

what i think you're talking about though is some kind of sealant or gasket to go between the two to keep water out, right? gaskets can sometimes help things rust faster because a lot of times they help retain water that would otherwise roll right through and evaporate. when you have an item that is holding water over a surface for a long time, it breaks down the finish faster than if it was just left exposed to the elements. so in my opinion, no i would not advise putting any kind of gasket or sealant between the two.

as an example of this, take a look at some of the newer Ford trucks (if they have them in NZ?). The 2007+ Ford F series trucks, especially the F250 are rusting out faster than they ever have before because Ford decided to load the things with all kinds of foam and fillers on the underside of the body panels. Right over the rear wheel wells the bedsides are rusting out incredibly fast. That's due in part to the fact that they have large foam blocks behind there that hold water against the inside of the panels and don't let it evaporate away. 2007+ Ford vehicles are looking like they're 50 years old in just a few years.

one easy thing that you can do to help prevent rust under the striker is to blow it out with compressed air each time you detail the car. you're obviously cleaning the jambs anyway, so just give it a quick blast of air to make sure there's no trapped moisture. if the jamb gets painted correctly, and you take the extra step of blowing it out once in a while, you should have no problems at all.

 

I wouldn't try painting that because that's "Mr Rust." He's there so that car have cancer. IF you don't want "Mr Rust" to return from the dead, then best thing you can do was to cut it out and weld it back there with another sheet metal. I promise he will never come back there.. Period..GOod bye "mr Rusty."

YOU can try painting it but it going to be temporary..

 

well all childish nicknames aside, it's very easy to get it to not return, you just have to pay close attention to what you are doing. if you see nothing but shiny new metal, then you've taken care of all of the rust. a wire wheel isn't always the most complete way to remove the rust, but you can always hit it with a Roloc disc or flap wheel to get what remains. using a high quality metal glaze or filler (that is specifically designed to be applied over bare metal) and then etch or epoxy primer will be sufficient for rust prevention.

if you want to talk about some severe rust returning, then go ahead and weld in a patch panel. lol. when you weld it destroys the coating that is already nicely covering the underside of the panel. you always use panel bonding adhesive to make rust repairs if at all possible. the only time welding is acceptable is when you can easily access the back of the panel so that you can prep and coat the welds. if you weld a patch panel in where you can't reach the back of the panel to coat it, then you're just leaving bare metal exposed to moisture, in which case you might as well leave the old rust alone because it's going to come back and be worse than when you started.

 

In this case then might as well get another vehicle that doesn't have any cancer. Rust very hard to maintain for most peoples because once it there it's there. Most peoples would say why bother fixing rust when you can get new vehicle and don't have to maintain too often.

 

that doesn't even make the slightest bit of sense.

anyone who has been trained in collision repair techniques can tell you that rust is a pain in the ***. no doubt about it. however, it can easily be conquered by removing all traces of it. we're not talking about some kind of 3 foot wide hole in the side of his car. this is a small amount of pitting under the door striker. the rust has obviously not penetrated the surface, and is obviously not spreading past the point that he has already prepped.

once the metal has been prepped and the proper repair procedures have been followed (no backyard special ****), the panel will be perfect for a long time... more time than you will probably own the car.

 

oh man thanks for the help guys :D