Best way to treat small rust spot (and keep things looking good)
 

My car has a small spot of rust developing right at the windshield gasket. Previous owner said it started after having all the rubber replaced and thinks a scratch through the paint is the root cause. I also noticed the rubber wasn't sealed well up higher on the post so I think water from washing was getting under the rubber and collecting in a semi sealed environment.

Any ideas on a short term solution that will keep the car looking good and put a stop to any further damage. I've used Rustmort in the past on other projects. But don't want to dump some of that down inside the post without thinking through all the possible reactions. Any help/advise would be appreciated. I can live with a little blemish as the car still looks nice. Thx, Todd

http://farm9.staticflickr.com/8325/8...fd0e20a1_b.jpg
photo 12 by todd2302000, on Flickr
http://farm9.staticflickr.com/8330/8...a128d105_b.jpg
photo 1 by todd2302000, on Flickr

How temporary?

Looking at the photo, you can see the seal distorted above the bubbles in the paint--rust. The only way to address this is to remove the seal and inspect the extent of the rust. Any topical "solutions" applied without removing the seal will do little to slow the process unless the area is thoroughly cleaned, and the rust will continue to creep under the painted surface and eat through the frame under the seal.

Have you lifted the seal to peek under to see from where the rust is emanating? If it's bubbled and flaky, as indicated by the distorted seal, it needs to be scraped and cleaned to slow further damage. In short, if you are going to address the rust fairly soon, I'd leave it alone and wait and do it correctly which may mean cutting away some window frame and installing clean metal.

This is just what I would do if it were my car. Others may offer temporary solutions but keep in mind, the sooner you fix it correctly the better you will rest at night.

Rust is like an iceberg, you only see the top 1/8 and there is a lot more beneath...
New metal is the only permanent fix.
A good bodyshop can pull the windshield, replace the bad metal and blend the paint on the cowl.
Get some quotes and then have it done right. (unless you can do it yourself)

I'd like to keep the paint as is for as long as possible. The car is a driver. Thanks for the info I plan to get some quotes. Makes me nervous to wash it! Been shooting a little WD40 down the seal to help displace any water.

Unfortunately, that is a hole about the size of a quarter (sorry to be the bearer of bad news). The only way to truly fix it is to remove the windshield, grind out all the rust and weld in a new piece. Once you are positive you got it all, apply a good epoxy primer and repaint. Not addressing it now will simply make it a bigger job.

You might consider something like Kroil instead of WD40.

Gotta get the windshield out to assess accurately.