Newbie rust repair question...
 

My sedan has only one rust spot on the right rear fender and it's a good one - check out the pic. Question is, what's the best way to fix it - is this a DIY job or is this a job for a bodyshop - don't need perfection here just something that will do the job right...

Suggestions for DYI work please (links welcome). Also, if a bodyshop were to do this work, what would be a reasonable estimate?!

MF

Well, its a DIY job if your familiar with welding and such. DIY is all in the skill set of the person doing the work. The pic of your spot is hard ro decipher since its xoomed in so close. I cant tell exactly where on the qp its located. However, its looks like a pretty easy fix. Can you access the back side of that area?

Looks like pass side rear fenderwell behind the wheel at the trunk well. That's a rust point since about three sheets of metal converge there with welds and all that that entails, and if you have a leaky rear window seal, the seal can leak into the trunk well pooling up at that spot. Water can get trapped in that spot. Take the trunk liner out and scope around on the inside there and you'll see how it can happen. Leaky taillight seals can cause rust too. That's pretty rotten under there, I initially thought POR it but you really need to weld in new steel.

Looks like a real project...
 

Yes - that's exactly where it is... I've pulled the liner out and it was not as bad as I expected though it's definitely ready to be rusted through the corner spot where the real damage is underneath... Sprayed it with Cosmoline to 'preserve' it until I deal with it... Yes, I think I see the rear window seal issue too... wonder what it takes to fix that?!

Man... that sounds like a real project... not sure I'm up to it since I don't have any equipment to do it... buying a $300 welder and all the trimmings doesn't sound too appealing at this stage... have to re-think that...

Why is welding necessary - someone else mentioned that it's a structural issue - it seems like such an out of the way place and structural strength seems like the least of the concerns in that area of the car... :confused:

Welding is the only permanent way to fix it. However, welding done wrong is far worse than doing nothing at all. If you dont want to weld in a patch, then I would first clean the area. Pull off the heavy scale and rough up the paint around the rust a bit. Then use POR 15 to seal it. Leave it like that for a bit. Long enough for it to get wet a few times. Then check for new rust. If it stays clean you can start to cover it. For the quick method, use fiberglass resin and mat. Once you patch it with the fiberglass you can sand it smooth and paint it. A patch like that will be good for a while.