Roof pillars, body lead replacement?

[great white]

I'm tired of dealing with the body lead in the pillars. Both front and rear have rust in them and I have to cut it out. It's the second time for the front pillars.

Body lead just doesn't get it done around here as it rusts from underneath the lead and works it's way out. Causes it to lift, the metal to pinhole and it all just cracks and separates sooner or later.

I would suspect it's the heat needed to do the body leading that gives the rust a foot hold and then it's all downhill from there. Flash rusting is impossible to stop here (evident literally seconds after blasting) and hot metal is even worse.

My plan is to cut the cancer out and weld it back together, then rust coat the steel and weld "plates" over the depression where the spot welds join the panels. Finish with a light skim of polyester body fill.

I've seen a few friends try it with just body fill (reinforced), but it cracks far too soon for my liking and then you're right back to square one. Worse actually, as then water can work it's way down and under the filler. Filler is sure easy to shape, but just not durable enough for the location/use IMHO.

I'm just curious as to how others have dealt with the body lead replacement on roof re-skinning.

Please, no "opinions". I'd like to hear from those that have actually done this job, how it has held up over the years and things you might do differently if you were to do it again.

[wraithracing]

If you look at my build thread you will see what I did with my roof to quarter panel repair as you are discussing. Bottom line is too keep your filler to less than 1/4" thick and preferably 1/8" or less and you will be fine. Good Luck!

[dagenham]

For what you are doin I would invest in the 3M epoxy set up that I have referred to before. Once the steel is bare the epoxy acts as a glue and a sealant all at the same time. The gun is the only thing that can be expensive for this way but it is worth it in the long run. I have used this for multiple projects and have not been dissapointed yet.
For this project your getting into with this car it would make your life easier. Work smarter not harder

[erratic50]

I've dealt with this problem on multiple cars before. We would cut out ALL of the offending metal - be particular to cut it all out - then apply weld through primer

for some cars we had to remove the windshield and tack a brace inside the pillars then cut out sizeable sections of body skin and underlying frame and put new metal back in. Be careful to do a good job as this is structural!

For metal patch panels, nice thick metal from crashed luxury car hoods is tough to beat.

On some cars we welded in both ends of the patch repair in entirely a little at a time then ground it out flat and tapped it inward with a body hammer as required to either get it smooth or 95% of the way there then filled. (See below)

Some cars were a lot straighter than others. When filler had to be used, we used an epoxy based filler called rot out. It gets its name because that's the only way it's coming out or cracking. It's water proof fiberglass reinforced epoxy based Bondo.

its been years since I've seen many of these cars as I am not in that line of work anymore. I recently saw one we did in 1991 and it still looked great.

Another key - fix your body flex. Subframe connectors are a must on fox body cars with anythibg more than the base 4 banger. Even the old base 5.0 that was non-HO has enough torque in the long run to yield cracks without them!

Also inspect factory weld points for floor, firewall, rockers, etc. if the panels have broken loose the body will flex violently and this is causing your cracks.

Back in 1996 my Mustang went into the body shop with a frame caused driving issue. Punishment with Slicks and 4500 RPM drops yielded a 1 7/8" twist in the unibody and there was a diagonal crack in the floor. All of this had to be corrected and subframe connectors added and stop running slicks to resolve my cracking.

[dagenham]

Compare able to rot out is a product I use called All metal. It is basically body filler with aluminum in it. Once it cures it is hard enough to drill and tap, is waterproof and is hard as heck to sand once cured.

[erratic50]

I wanted to give some context on the strength of the stuff we are suggesting.

In 1992 the body shop my dad worked at doing fiberglass repair took in a 1968 Corvette 425HP/427 4-speed numbers matching car for repairs. There was just one problem - an engine fire had melted the front clip and most of the left side of the car including the rear quarter and part of its iconic back.

Back then many parts like frame rails and front clips and T-top roof sections and doors and the tail end of the car were readily available. What wasn't available was a complete replacement rear quarter panel.

The car dealer that bought the car had us take the needed section out of another car in the shop that was there with chronic fiberglass cracking issues in the rear quarters. We made a mold off both sides of this bad panel and poured new quarters using rotout as our body material and glad mesh for reinforcement and put fiber mesh in the edges to seam it back into the glass of the cars.

We we did a similar thing to a Fiero body panel but used cardboard as a mold for that POS.

We proceeded to fix both vettes by pouring gallons of rotout into our mold with mesh.

One car we never saw again in the shop. We saw it years later at a car show, still looked great.

the other car got spun in a circle and hit a pole during heavy rain going backwards right beside the repair joint. The entire section we made actually ripped out of the car and landed in the ditch intact but submerged. Not a crack in it anywhere. We got the wrecker call so we grabbed the section when we loaded up the car. That very same section went back into the car after everything else that was totally trashed was replaced or fixed and we never saw that one again either.

Several cars after classic fiberglass repair techniques failed also got the cut out cracks and redo with rot out trick too. Once we started using it instead of traditional body supplies we never saw those again either.

I once fashioned a replacement front fender for a 125 Enduro using only rotout. I dumped the bike several times and once it ripped the heads off of the 8-32 bolts that held the fender on with minimal damage to the fender. No cracks, so I just put it back on.

I wish I still had the racer I helped a cubscout make out of rotout. Body was just poured and shaped from rot-out. Wheels were later molded from the originals in the kit and fashioned from it too after the originals broke in a mishap. Fastest cubscout car I've ever seen.

My point is the stuff is insanely strong. Not your average bondo to say the least. It stays true enough to the shape that it dries in that I've not seen paint crack and come off of it before. Really impressive stuff, especially for the early 90's.

[91svtcoupe]

Putting a roof skin on my 87 car now. with that being said my body guy heated and melted out all the lead joints and we cut sections from a Donor car we had to replace it, welded on both sides of the patches, car is not finished yet so I can't comment on how the will hold up. But here is what it looks like at this point.

[erratic50]

Looks good so far

[JTurbo]

My 82 GT repairs:






Full details are in the link in my sig....

[erratic50]

The rust under there concerns me. Extends and other similar products slow cancer down but it doesn't take long to rust through body panel metal. I believe I would have went deeper with that repair.