Just a touch up, darned rust!
 

Today I continued the task of tackling the rust bubbles behind the rear beauty bar!!

https://cimg7.ibsrv.net/gimg/www.che...e1bc050d3.jpeg
The driver’s side chip on the end
https://cimg8.ibsrv.net/gimg/www.che...d13b30c44.jpeg
Driver’s side by the fastener hole
https://cimg1.ibsrv.net/gimg/www.che...15618702e.jpeg
Similar over here on the passenger side fastener hole

possibility that the nuts were tightened to much , possibly that road grit and winter salt and sand got in between the bar and the painted body surface.
There photos show with a coat of rust encapsulator on the sheet metal, I used a razor blade to cut away the paint to expose the rust. A little sanding to give grip to the primer coat .

This morning, I applied the self etching primer, I used an old Tupperware dish to spray some paint into , then used a dollar store touch up artists brush , to save from taping , masking and over spray! It’s an 11 year old car, so I’m sure it’s just a DD no more car shows.

https://cimg5.ibsrv.net/gimg/www.che...75c168ff2.jpeg
Driver’s side end
https://cimg9.ibsrv.net/gimg/www.che...84be22b18.jpeg
Passenger side above the fastener hole
https://cimg0.ibsrv.net/gimg/www.che...c7ab46864.jpeg
Driver’s side above the fastener hole

Later today, it’s colour coat time!! Then clear and reassemble the beauty bar and interior panel

That will be bubbled again in 6 months. You can't have any rust. Even using acid to neutralize the rust will not work unless it gets all the rust.

https://cimg0.ibsrv.net/gimg/www.che...40ff05d13.jpeg
Rust encapsulator coated on, let cure for 24 hours
https://cimg2.ibsrv.net/gimg/www.che...a095aab10.jpeg
Etching primer let cure 6 hours Still no rust has returned. I’m keeping a close eye on it. I agree if the rust has broken thru from the other side of the panel.

Surface rust can be taken care of easily but when it bubbles the paint the underlying rust is deep into the metal if not all the way to the other side. It all needs to be exposed and taken care of or it will bubble again.
I hope you got it all.

When was that fender repair performed?

The fender repair was done on the BlackSwan , April 27 to 30, 2022.
I made sure I exposed all the surface rust under the paint. Otherwise I wouldn’t have wasted the time or materials, you have to apply the rust encapsulator over some rust, not loose flakes, but not soda blasted either.
I’ve sand blasted, soda blasted , POR15 painted many rust repair jobs over the years . This new chemistry encapsulator may work , it might not, only one way to find out.
I thought I would share the information with everyone here on the forum.
I’ve known for years , if the rust bubbles thru the sheet metal, cut it out and TIG weld in new sheet metal .

Colour coat done , and after supper it was dry enough to reassemble the beauty bar

https://cimg6.ibsrv.net/gimg/www.che...4919c2fa3.jpeg
It’s not perfect, but neither is the rest of the car
https://cimg9.ibsrv.net/gimg/www.che...daeafec35.jpeg
The driver’s side end
https://cimg0.ibsrv.net/gimg/www.che...cfbe7eaf6.jpeg
The passenger side .

Sounds like you did it right. If we had rust that went through any part of a panel or piece we would cut it out and fab new or glass it. Of coarse it helps when you have the tools and such to do that kind of work.

I sold off all my shop tools 25 years ago, used to built race cars from spring till summer, fix rust holes during the fall and winter. Learned all about rust over the last 60 years working on my dad’s car’s, he used to flip pickup trucks , and Cadillacs and Lincolns. Now I’m not allowed by city to have torches, plasma cutter, welders, my insurance company wouldn’t like it either. So, rust encapsulator is the extent of my work now.