Date: Wed, 15 Sep 1999
Glenn
I purchased a 1969 1800S about a year ago. It ran, but didn't stop, so the first thing was to fix the brakes. It was then a perfectly good car mechanically, but unfortunately the body was somewhat the worse for wear - mainly the rocker panels and floor panels.
Like you, I bought myself a MIG welder and am about to start restoring the bodywork. I built a frame for the 1800 and rolled it onto its side so I could have easy access to the underneath (see attached photo).
I bought some 16-gauge sheet steel to start repairing the floor with but I'm having second thoughts about whether this flat steel will be as strong as the original corrugated sections. Can I ask what you used to replace your floor panels? Did you buy custom-made ones or just start with flat steel sheet? In my case, it's really just the outer 4 or 5 inches of floor panel that will need replacing, so I'm hoping to avoid having to buy whole new panels, but on the other hand I only want to do this once!
Thanks in advance.
Rod MacLachlan
Rod - Thanks for the picture. As for the welding, the placement of my story on the Volvo page may be a little misleading, since all the welding I've done has been on my '61 Austin-Healey Sprite. Well, I don't have a Sprite page, so . . . .
Anyway, to answer your question, I used 22-gauge flat steel to replace floor panels in the Sprite that originally had only a single indentation in them. They were small panels in the footwells, and I was confident that the flat steel would work o.k., because there was hardly any weight resting on it -- just my feet.
I also replaced a 5x24-inch section under each seat where a support beam rests on the floor, and replaced the beams, too. Again, even though the original was corrugated, I used flat 22-gauge steel to fix it. This time I reasoned that the support beam would provide the necessary stiffness. The best way to repair the floors would have been to buy new panels, but I was not up for that much work or expense.
One thing I was worried about was how I would get access to the underside of the car, which you seem to have solved neatly. The other worry was keeping the body from flexing while welding in such large sections. If you do replace the whole panels, make sure you have plenty of support. I've read where some people have welded tubular cross-braces into each seat well before removing the floor panels.
To apply my experience to your situation, I'd say if you want to do the best job, and you're prepared to handle the work and the expense, get new panels. Otherwise, use common sense and a careful assessment of the stresses caused by seat placement to decide how much flat steel is enough. Also, I would encourage you to consider whether the added weight (and reduced power-to-weight ratio) of 16-gauge steel is worth any extra durability it might provide over something thinner.
I drove the Sprite for five months before I had to park it for mechanical repairs (and to wait out the heat of summer), and the welded parts held up fine. I'm planning to drive it again this winter, starting as soon as I fix the rear brakes -- hopefully this weekend. The air-conditioned P1800 will spend the winter in storage if all goes well. -Glenn.