Rust can be an issue with modern vehicles, so imagine what it's like on a 30 year old one. Well, it can look like this.
The below two pics are the right and left rear window sills on the inside of the van. So I guess the windows had leaked in the past. I made all the windows watertight a few weeks ago. But as you can see, pretty serious rust to sort out.
This was the inside of the sliding door:
The first step is to scrape the loose rust and paint off (note the frost on the window).
Then you put Kurust on the rust to treat it.
After a couple of hours the Kurust turns rust into a solid paintable surface.
Now, the bit where there is a gaping hole needs filling. You hammer the edges of the hole so that they are depressed (before applying the Kurust). You then stick a piece of mesh over the hole using P38 filler.
Then when that is dry you can use more P38 to fill the hole (messy).
When it's dry, you can sand it smooth.
It can then all be painted. Colour doesn't match but the rust is gone which is the most important thing. We may respray correct colour in the future.