Dealing with Vintage Radio Chassis Rust

The Trav-ler Model 5020 I had recently acquired had a fair amount of rust on the edge of the chassis.

Here is a picture of the rust from a side view.

The rust was caused by a leaky 4.5Volt Zinc-Carbon "A" battery left in the case by the previous owner.

The chemicals in this vintage Ray-O-Vac "A" battery had leaked through the cardboard case then attacked the steel chassis where it made contact.

The first step to chassis rust repair is to give yourself some room to work. I removed the vacuum tubes in the near proximity. I later decided to unsolder the red and blue wire that connects a AF (Audio Frequency) amplifier tube socket the audio transformer then pull the wires out of the grommet. Then the grommet was removed as there was rust around the feedthrough hole.

I started with a Dremel with a grinding wheel installed to remove as much of rust as possible. I then sanded the rusted area starting with coarse sandpaper finally finishing with a fine sandpaper. 

Here is a closer look of the sanded edge from bottom view. 

Below is a picture of the area masked off ready for paint. I used denatured alcohol to degrease  area before paint.

I use silver Dupli-Color automotive rim paint as it is the closet color I can find that matches the natural color of most chassis. Apply in light coats and feather it out so as to make a natural transition from the newly painted area to the chassis color.

Automotive Rim Paint on Amazon! 

Repair job complete! Time to install a new grommet in the hole then thread the audio transformer through the grommet and solder to the AF (Audio Frequency) amplifier vacuum tube socket. The final step is to install the vacuum tubes into their respective sockets.