Thursday 20 August 2020

Sill Box Section Repairs

One job seems to lead to another......

Unfortunately the work to replace the non structural outer sills revealed more jacking damage!  This time to the box sections. The damage was just rear of the proper front jacking point of the car. And on both sides! At some points in the dim and distant past, someone had jacked up the car from under the edge of the main sill - on the fold.
Rust on the sill!
The fold is the join between the floor pan and the outer face of the main box section.
The damaged area is shown by the red circle
The edge had folded slightly - breaking through the underseal. I might otherwise have left this, but, over time, the creased edge had rusted through......
The underseal promotes AND hides the rust
I removed some of the underseal to assess the damage. It was just the folded seam that had rusted - a length of about 20 cms long and 2cm deep on both sides, however repair work meant cutting into good metal slightly higher up.
Cutting out the rot
And on the right side of the car, the folded vertical edge of the floor pan  - that I needed to weld against - was also badly corroded. Meaning that I would need to let a patch in there too.
The area behind the spot welds was also corroded
I cut very slightly into the floor pan, then formed a profile in a vice and cut a piece to suit. 
Forming a patch
The fold in the patch meant I could butt-weld a flat edge to the floor pan, rather than trying to weld a patch on at 90 degrees.
New 'lip' welded on
The new lip gave a good clean edge to weld-to and the patch was soon fitted.
One done, one to go....
The repair on the other side was similar, though no patch to the floor pan lip was needed.
Note the plumbers matting to protect the pipes from cutting and welding.
The rest of the sill looked to be in good shape - though the Waxoyl I had sprayed in , in about 1995, had dried out and curled up. It's Dinitrol for me next time!
The floor pan in the sill looked good
Another patch was cut and fitted. 
Sizing the patch for the left hand side
With both sides repaired, surely now I could press on with replacing the outer sills? Well - maybe  not quite yet......