Whats the best way to get to bare metal?

[vol96]

I'll be doing some rust repair on my 73. To make sure I get it all I want to get to bare metal around front bumper mounts, front inner wheel wells. I'm going to remove fenders and doors.

Also need to remove right outer rocker and need some advice on how to do this. I'm not sure of where to cut so as not to damage inner rocker or other parts. I suppose I could make a horizontal cut down the middle of the rocker then bent it outward so I can see how its constructed and asses the extent of the rust. Is this a bad way of doing it? I've cut out 2 small rust hole on the outer rocker and inner rocker looks good as far as I can see.

Also, I've cut out about 3" square section of right door latch plate (bottom section of course). Thru this hole I can see that the rocker panel support is almost half rusted away.

The car has lots of aftermarket 'rust proofing' that was applied back in the 70's. This stuff is like grease tho thicker and stickier. Off course its on top of factory undercoating. Its going to be a mess getting it off but I bet the car will be 50lbs lighter if I get all of it. To get to bare metal, both the rust proofing and undercoating of course have to go. Gonna be an 'all winter' project unless there is a quick and easy diy solution. I dont want to throw money at it (ie take it to a shop), but dont mind buying tools and supplies. What I mind is paying someone to do something and then finding out later that I could have done it myself. I've got fairly complete set of tools and equipment... air compressor and tools (no air hammer/chisel or nibbler), angle grinder, die grinder, dremel and will be getting a mig welder.

I really want to learn how this is done so I can do more projects like this.

Forgive my rambling and thanks for the advice/links/pointers in advance.

Joe

[Larry Harris]

Joe,
The last time I attempted something like this was when I had my Pantera engine out for a complete rebuild (351 Cleveland). The factory sprays or brushed a rock hard coating of some kind ALL OVER the engine compartment. Its abour 3/8 inch thick and as I learned a scraper will just bounce right off.
I finally bought some aircraft stripper (burns like hell if you get it on yourself). Work a small arear 2'x2'. Let the chemical work for 15 minutes and then scrape it off. You will have to repeat a few times. It will remove any paint it touches and really makes a mess, but it works.

Make sure you get the commercial grade they used for stripping aluminum aircraft. Stop by a local airport and talk to the people that are actually involved in the repainting process.

Good luck,

Larry

[Zeke]

The outside rocker is attached by a row of spot welds along the bottom and under the threshold. Make a veritcal cut at the rear quarter right at the rear bottom of the door. There are a couple of spot welds at the front too. Should expose the inner rocker at that point. Proceed with inner rocker and jack receiver as needed.

[sliminbay]

The aircraft stripper works great but use with caution. Stay away from panel edges as it will "unglue" the joints were two body panels are joined. A friend learned it the hard way on his 911 which ended up in parts heaven.

[davis911s]

Slim what do you mean about the ungluing of the joints? I one day plan on repainting my car and was going to strip it down so please explain

Shawn

[sliminbay]

About 4 years ago, a friend was doing frame off restoration of his 67 and got into trouble when started to strip paint off to change color of the car. From what I been told about the incident and from pictures, parts of body panels where it is roll over to give strength, like back end of front fender, are glued then folded. From what I saw in the pictures, the aircraft stripper melted something out of the area and the area lost integrity. His chassis was ruined due to same problem where top of the car meets the side panels, near b pillar and rear window. Apparently he did similar stripping of paint on his other cars using non-industrial strength and had no issues. Apparently aircraft stripper is much stronger. And I can testify to how much better it is then others. When I started to work on my current 74, I was told of this incident. I do not have more details about what porsche did for manufacturing practice back then. My friend and I are using the aircraft stripper on my car but away from edges. We are using sand paper and wire brushes.
Wondering if any others on board have more information about this "glueing" of body panels?

[svandamme]

do you mean where the panels that attach to the nose?!?

yes they are glued/bolted , but for a good anti rust and paint job... you want to unglue them anyway..

at least that's what i'm doing, i'm talking stripping the car to the chassis, then clean everything to the bare metal , cut out rust, weld in patch metal or replace , then re-prime, repaint , reassemble > bolt and glue

EDIT > the structural integrity of the car doesn't depend on that glue, those panels are bolted, don't carry any load other than their own weight, the glue is used so you can make the panels fit withing specs, and have no metal ratteling...

second edit > the back of the front fender is not folded over..

it's 8 or so bolts, and lot's of kit glue
there's no metal folding , it's bolt plate plate nut

after the glue it's boltglueplateglueplategluenut or however creative you can get the panel to line up exactly with the other parts and have it stay there without rattling

[jpnovak]

Stripping with chemicals can be really messy. besides you have to wash the surface post stripping.

I used a 60-80 grit wheel to buzz right through paint. The flap type work really well and don't heat/warp the surface like a solid wheel. Go down just till you almost see metal then switch to a 120 grit. 6" DA's work well on the flat surfaces.

Undercoating will not be touched by the strippers. I tried them all and they just get gooey and smear. Best results were using a braide/knotted wire cup brush. Makes a huge mess that is easily swept up with a broom.

Be prepared to spend lots of time with the grinder if you go this route.

Jamie

[svandamme]

Jamie, your car is tha bomb !!!

i'm currently doing some long distance planning dreaming bout getting in to classic rallies, specifically the Ypres historic... the 911's usually get excellent scores there.. as in 1 2 and 3 spot

yours looks just as i remember the 911's in the old days in the 24 hours of Ypres...