bodywork problem; how to...?

[eriknetherlands]

I am in need of advice.
I purchased my 3.0 cs of 1973 roughly 2 years ago ad have driven it ~8000 km's since. It has given me no real problems, so i'm about to tackle some rust this winter to make it even better.

Floors and rockers are quite ok, but there just this one place that i don't know how to tackle.

The area that has me puzzeled is under the rear seat, where the left and right attachement points of the rear subframe are.
The floor is rusted through, but the reinforcement plate's seem to be solid, see attached photo.

2 questions;
-are there NOS/replacement parts for this, or do I have to chop up another body for this?
- I was wondering if i could replace the part from the underside, without removing the reinforcement brackets? Should I make a little jig, keeping the reinforcement brackets and attachment points firmly in place, while taking out the rear subframe, and welding all from underneath the car?

Bodywork is still quite new to me, so any tips, tricks & hints are welcome.
I'm not taking on the whole body, but what I fix, I wanna fix well.

Advise on 'howto' is welcome.
Regards, Erik.

 

[Henrik]

Hi!

There is no replacement plate for this area, so you have to make one yourselves. It is a very simple piece to make. Use 1mm sheet metal.
My advice is to remove the rubber mounting pin and, remove the reinforcement brackets (drill out the spot welds)
The access to the rusted area will be much better, and you can weld it from the top.
It is very important that you support the rear subframe, or better, remove it and make a jig as you suggest.

Underneath the reinforcement plate it will most likely look the same as in my car (photo)
It is important that you have the right distance between the to pins.(photo)

Henrik

 

[61porsche]

Erik,

A photo from the other side would help describe how best to go about a proper repair.

The area is a seam. Just as with a collision, you must determine where the damage origin began. Karman was known to be short on seam sealers vs the other body makers of the same era in Germany. ( D'Iterin,etc.)

It will always be easier to weld a repair from the top than underneath or overhead.

Think of the repair as a puzzle. And replace form the most inner and work out.

The damage does not really look bad. Small pieces of 16ga. can be made up as angles to do a curve. Do not use anything thinner here.

Open up and clean the seam. It's likely it started up a little higher, wore off the undercoating, sealer, found the seam and travelled, until a hole started , then because of the wheel action, water was slung on the back wall as seen in the rust stain to the left.

But again, show us another picture.Then we can begin the ,"how to" in detail.:-D

 

[Stan]

And checkmthis site for tips to add support while you are fixing this area.

http://www.coupeking.com/category_id-80.html