My Rust Remediation Project

[DSouth]

Ahh......a new project.... I decided to investigate what look like a smallish rust hole from the outside (underneath the car). I've worked on some older cars before so, I've been around the block with rust, and know well the whole "what you see is only a small portion of the total actual" adage.

Here's what I saw, after tearing out the back seats.





It seems to me that it will be easier to replace the whole rear seat panel, rather than trying to cut out the bad rust spots, and making patch panels.

I have some questions though.

Is this panel structural? If so, should I put in some bracing in before I start cutting spot welds?

I plan on grinding/wire brushing off the seam sealer, then cut the spot welds, so I can remove the rear seat bucket panel from the inner fender area, and then cut straight across just below the package tray area.

On the bottom side, should I remove all the way down to the floor pan?

I'll post pictures of my progress, from removal, to replacement to undercoating, and the re-addition of interior sound deadening.

-Dave

[Porsche_monkey]

Personally, I would cut out the flat section of the bottom of the seat and stitch in a repair plate. Trying to replace the entire panel is much more difficult, and no one will ever know which repair you did.

It is not 'structural', you do not need to brace.

[robmog]

shaun (shaun84targa) has the piece you need if you want to do a nice job.
see here:73 Rear deck and seats
IMHO a longhood shouldn't be cobbled together.
bob

[magnuskgc]

I am doing the same project... pics would be great and I can forward mine along too

[Zeke]

Definitely weld in only what is thin. Cut out to where the metal thicknesses between the replacement part and the car are equal, no exceptions. You could very easily lap weld this piece and seal with poly body caulk on both sides. That would be a plenty acceptable repair.

Yes, the whole thing would be considered structural if you were to remove it from quarter to quarter. The thing is, any welding should be done over a period of time to allow your panels to cool naturally between sessions. We usually skip around rather than weld for a long period in one place.

Tack it in at four places, then divide the distances between welds in half, tack some more and so on.

[DSouth]

Well, I didn't get to any cutting this weekend. I spent most of my time cleaning up the garage and making room for the parts from disassembly. In the process I also found some more rust on the package tray So, I guess there was a leak in the rear window seal.

Here's some more pictures:

Original foam and sound pad.


Passenger side package tray


Driver side package tray


Rust hole in package tray at the back driver side corner, where the defrost wires come in from the engine compartment.......sigh......


So, originally I was planning on removing the rear seat bucket panel from inner quarter to inner quarter, and replacing it full stop with donor metal. Now, with the discovery of the package tray rust(I guess I should have expected this), I would also be faced with removing that panel and replacing it also.

I hear a couple of people (Milt and Porsche_Monkey) saying the best way to go would be to stitch in replacement pieces to the thin areas of metal.

Here's a first pass of some areas that would need patching. (Circled in Black)






So, I'm looking for some opinion. When I look at all the pieces that need to be replaced, it makes me think that replacing the whole panel would take less time. Opinion from those who have replaced either of these panels entirely? Would you do it that way again? I'm all for patching in the bad spots. I have some concerns about patching some of the compound curved areas. What gauge metal are these factory panels?

[Dan Morton]

I'm in the same boat with my '68. Rust in the parcel shelf and some in the fenders where it attaches. Fortunately the seat bottoms are fine. I am still grinding to expose all of the rust. Right now I'm looking to fix with sheet metal patches but may look to get a complete shelf if I can find one at a reasonable price. I'm anxious to see other replies

[Shaun @ Tru6]

remove the rear window, get a proper respirator, angle grinder and a few 40 grit flap discs and a large brush cup and have at it so you can see where you have good clean metal, thin metal and perforation.

it won't look like this, but all of the good metal left should. Anything thin or perforated should be cut out and patched, but at some point patching becomes a bigger job than replacing the whole thing.

Thanks for the reference Bob, appreciate it.

[Zeke]

I didn't mean to infer that I would piece meal lots of patches in. I'd draw a line around each area that has to be replaced and cut out the shape. I'd probably square up the shape to make the repair look good.

On the trays, what seems to go is the very edges. When you get the donor piece, likely it wont have the original flanges on it. I've made those flanges to attach the tray to the sides. You could make an exaggerated flange (sort of a long "L") that reached out well into the field of the tray and probably be done with it.

These pieces don't run straight for any considerable length, so your abilities will be tested.

[Fishman7]

Shaun,
Nice work!

[DSouth]

I'm going to spend some time with the grinder and find out exactly how bad some of the rust spots are. Then I'll take some more pics to show what would need to be replaced. I'm curious to hear from those who have been here before, when does it become more time effective to replace the whole panel versus patching?

[Zeke]

I'll put it this way, a whole package tray took me 24 hours the first and only time I did it. I can do a front pan in 8 to 12 hours, depending. It took me over an hour to get the tray out of a wreck and I cut everything in sight. It took another 2 hours to separate the tray I needed from the portion I cut out of the car.

[Conda Green 71t]

I just took a look at this thread - Oh I thought, some one has found my car and taken pictures of my parcel tray!!!

the tray I have been looking at for weeks now wondering just where to start.

Also in the same rusty shade of conda green. (that's not rust - its old glue- right?)

when Im done looking at the parcel tray - scratching my head wondering if the mig still works, I look at the front pan..... ( or where it used to be) then when Im done doing that I speculate about about the state of the inner sills..... (probably rusty too)

I then head inside for a trusted remedy...........

Drink until I stop thinking about it and hit the internet to debate the finer details of leather versus vinal - Im quite drunk by now so of course it's going to be the leather - and to hell with it I'll take a pair of new 69 - 72 door pockets......

You get the picture!

Good luck and keep us posted.

Tom

[Fishman7]

Funny Tom! Remember my advice!

[Conda Green 71t]

Eric,
Very tempting right now!

Sending you a PM

[DG624]

Seems like it would be much easier to have the car sand plasted (maybe not sand) rather than doing the grinding. Shaun how do you rate the POR15 product and have you used rust remover as a first step? There are many products and I have to do some rust repair.

[Shaun @ Tru6]

Originally Posted by DG624

Seems like it would be much easier to have the car sand plasted (maybe not sand) rather than doing the grinding.

It's much better to get personal with the metal in this situation. the feedback from the grinder will tell you what you have.

[DSouth]

[/QUOTE]

Dan, I'm curious. Are those round holes that run vertically, along the back, just below the rear window frame, from the factory? Or did you make those? Looks cool to me.

Thanks for all the input everyone. There was a question about blasting the interior, the only problem is the outside paint is in very good shape, so I'd prefer to just take the time and grind.

[rvanderpyl]

They are factory, early cars had no electric rear defrost, instead they relied on warm air being blown through two tubes into the rear sheet metal and coming out those holes to keep the window clear. It worked just as well as you might imagine.

My rear panel was so rusted I had to cut it out and replace it. Good luck finding a suitable replacement piece if you want it to remain stock looking. There are no replacement new parts available, and as you can imagine, finding an un-rusted part from a parts car is pretty much impossible, especially since the early cars panel is different than later cars. . If you aren't worried about orginal appearance you can use parts from a later car, or fabricate something that fills the holes in.

[Shaun @ Tru6]

Originally Posted by rvanderpyl

Good luck finding a suitable replacement piece if you want it to remain stock looking. There are no replacement new parts available, and as you can imagine, finding an un-rusted part from a parts car is pretty much impossible, especially since the early cars panel is different than later cars. . If you aren't worried about orginal appearance you can use parts from a later car, or fabricate something that fills the holes in.

I have two of these, cut large, that are 99.5% rust free.