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If you check out my restoration thread you ll see all the same large areas I needed to refabricate / replace. It will give you an idea what your really up against. Then you can make a more educated decision...

 

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Detritus Maximus
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Matt-
Finding rust is always demoralizing, but not the end of the world. A little can mean the same thing as a lot. If you are worried about the quality of your welding on the outside, consider removing the outer rocker completely. You do all the cleaning /patching on the inner sections. have a sheetmetal shop bend up some replacement outer metal (it's nearly flat with some gentle bends at the bottom) and you cut and fit, tack it and have someone with more experience do the welding on the outer. At least you have enough structure to know what should be there, mine are just...gone.
 

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Discussion Starter #203
Sorry to say this, but you have much more steel work then you think..... What your seeing is only a part of the problem. I know this because I had to go threw it. You ll need to replace multiple layers of steel behind the panels that are rusted
That's my worry, but I don't think it's that bad. I'm hopefully not deluding myself with optimism, but I don't think it's that bad.

It depends on how the rust got there. I've seen what it's like on a bad car, my yellow one that I was not shy about filleting to get to what I needed. That was a Nebraska car that was continuously exposed to moisture both driving and sitting.

Here's a few reasons I think it might not be a disaster:

1 - I've jabbed the screwdriver around and pounded on lots of parts of the car that I was curious about how suspect they were. The only 2 non-fender parts before now that were confirmed bad.... one small hole by the rear sway bar mount, and, two little strips on the inside rockers right before the front-most drain where there was foam holding the moisture against.

2 - I couldn't jab the screwdriver through anywhere other the small section I did. It might only be that Post-It sized strip. The passenger side doesn't show any browning signs of rust coming through.

3 - The panels behind it seems pretty solid. The crumbling and rust does not proceed to the edges of the next seam. Hopefully that means it's confined to one layer, one panel. It looks like the mud caused corrosion to leach outwards only, not inwards yet. Probably because it was not a frequent event of being driven in wet with new water constantly being spun and shaken into the fenders (Arizona car). Plus the desert heat means it didn't sit cold and wet. It got wet, but it wasn't regularly exposed to new wetness. That's my theory anyway.

4 - The rust holes in the rockers are not at the lowest point in the rocker. The amount of powdered dust I shook and airgunned out of the car was huge. Perhaps it formed a protective cushion against moisture. This says to me that an amount of water got in and sat there, but not regularly, and not enough to "mix" with the dust and stir it up (not driven much when wet), not even enough to coagulate it or the bottom would be rusted first. If it didn't even stir up enough to move the water to the bottom, it probably didn't happen often.


I've always known the wheel wells would need some work and never poked at them because I wanted to leave them at least passably cosmetically intact. Originally my plan was to ignore most of it and just drive it for a year or whatever, fix that stuff later. Now I can see, no, I might have caught it early enough to not have to do serious rework, and I don't want to let it get any worse. It has to be repaired before I drive it a season.

There's more work than I hoped, and, if it ends up being more than just the outer skin...

That probably condemns the car for me. That's what I bought a desert car to avoid. Even this amount is borderline for me. This isn't a "have to do it no matter what" project, and the bodywork is not something that's fun for me, and... with my skills... is not going to be a source of pride, it'll be a source of embarrassment if I fix it myself, it's going to be ugly. I know my limits.

Again, I'm sorry for being "that guy"... I was really hoping fir the best, but this video really shows some major rust problems
Nope, it is what it is, no point in pretending otherwise and I always appreciate honesty.

I have a feeling it's not as severe as yours was because of the context of the process by which it got wet. Further exploration will let me know.

If you check out my restoration thread you ll see all the same large areas I needed to refabricate / replace
nod. That was my plan anyways. I'll use that to find out what's there and be educated about how to best fix it.

If you are worried about the quality of your welding on the outside, consider removing the outer rocker completely. You do all the cleaning /patching on the inner sections. have a sheetmetal shop bend up some replacement outer metal (it's nearly flat with some gentle bends at the bottom) and you cut and fit, tack it and have someone with more experience do the welding on the outer.
I'm not too cosmetically concerned about the rockers. That's a good strategy of just de-skinning them and having a look. The top is covered by rubber, so I could weld that. The bottom is under the car, so, no one will see that. That leaves only a pair of 4" strips around the sides. I might try that myself.

The magnitude of the patchjobs on the fenders is what intimidates me.

...

Moreso my concern is that I have to do it now, not later.

That's the thing that makes me wary of it becoming something I won't get around to finishing. The demoralizing part isn't the work itself, it's that I was motivated by feeling I was rounding the home stretch, certainly on bodywork. If I can drive it, then it's something that's useful to me that I'll keep working on. And if it's licensed it's not condemned to private property. As the list of things I have to do before it is drivable balloons, the longer I'm relying on the favor and inconvenience of others, and the bigger the odds of me saying no thanks, off to the co-op with you for dismemberment.
 

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Wish you the best..... I really hope things work out.
 

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Discussion Starter #205
Wish you the best..... I really hope things work out.
Thanks.

I'll try to take some better video of me poking and prodding tonight or tomorrow, maybe you or others can advise me what is likely okay and what seems fine but needs further exploration and demolition.
 

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Matt, I don't think the rust you are seeing is all that bad. Not all that good, either....

I have looked over your car fairly thoroughly. What you have uncovered is a bit more than I expected, but not surprisingly so. Old cars are rusty. 50 year old cars are ALWAYS rusty, even when from "dry" climates. My former Garage Find GT was stored indoors from 1978 until 2007, had only 28,000 miles, and was far more rusty than your GT. Not a big deal.
 

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Went threw my thread to give you some visuals
 

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.....more
 

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I also had to redo both bottom of the doors, large section of the lower nose area beneath the battery tray. As well the two large panels behind the headlight assemblies. Hope all this helps
 

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Discussion Starter #210
Well, did some more digging into the rust. Two weeks ago. Trying to stay motivated.

For those that enjoy sped-up rust pokin' 'n proddin':




Few notes:

- Driver's Rocker isn't in great shape, but appears to be worst just in a diagonal line. My guess is that it was parked outside, with the tail lights removed, on a driveway or hill at that angle, until dust settled. Annual Arizona rain rusted a single line through the metal there. The interior rocker has holes at the back but otherwise isn't too bad. I see a line of paint bubbles that seemed solid when I poked them but I'm thinking have to be where the rust bled through to a pinprick. Maybe best to just replace an extra 6" down that line.

- I don't know what those white goopy knobs are inside the driver's side rearmost fender, but, I'd suspected this car was rear ended at some point, lightly. Looks like those might be the fill scabs from dent pulling? Isn't obvious to me from the outside.

- Passenger side isn't nearly as bad, half the damage. Doesn't really matter, a slightly smaller or larger circumference doesn't add too much time, and the damage is mostly in a single plane so no complex curves, low enough that the wheel flares haven't sprouted form the side yet.

- Passenger rocker has no holes at all that I found. Rust spot is from the outside where paint wore off. Camera scope picks up a couple rusty patches inside, but otherwise looks great.

- Front wheelwells and fenders seem intact, couldn't poke a hole anywhere. So damage is confined to the ass end and the driver's rocker.

I'm not even sure where to buy sheet metal from affordably. Had an idea to just take a sawzall to the junkyard and cut the roof off a minivan or something equally sheet-esque. Then I wondered if the metal on a new car is more likely to be paper thin compared the GT. Maybe should try the side of a truck box instead. Maybe older is better? Will have to do that soon, summer is over, fall is here, snow arrives soon.
 

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You buy a sheet of steel. This one started as a 4x6 feet 0.032" thick peice and you start cutting what you need.

Baught this from a auto body and paint supply shop. Wasn't very expensive if I recall. This is what provided 90% of the steel used to refab my GT
 

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Detritus Maximus
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Even Lowes/Home Depot (or equivalent) sell sheetmetal in various thicknesses.
 

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Discussion Starter #213
Even Lowes/Home Depot (or equivalent) sell sheetmetal in various thicknesses.
Not here. Maybe 2 square feet and it's already pre-bent from the last 10 years of people pulling it in and out behind the slips of angle iron.

Heck, the place I usually buy my structural steel from doesn't even sell sheet metal.

I recall last time I wanted a some light sheet to cover a house door I gave up and just cannibalized an old whiteboard.



I suppose I do only need a few square feet.

Bodyshops sound like a good idea

That, or... I have 2 sets of doors. One set the bottom is rusty. I know I'm never going to use the doors again... I know I'm never going to repair the doors. I suspect I won't even attempt to keep the doors, especially if the co-op doesn't want them. I feel like I'm committing a sin, but, maybe I'll just chop up the yellow doors. As a bonus, the sheet metal will already be bent to the correct curvature.

Any reason not to?
 

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Discussion Starter #214
Finally made a go at casting with Zamak, after my first attempt struggled to maintain high enough temperature with aluminum.


Stunning partial success:

- This is a great way of turning $300 of conduit couplers into $3 of zinc.

- Best cheap source of Zamak I found was in old 2-hole punches. Just had to rip them apart and remove the steel punches and springs. They were a pound and a half each. Towel racks, cheap chromed drawer knobs, banister supports, and a CVT pulley from an old treadmill were all also Zamak.

- Zamak weighs 2.5 x as much as Aluminum. My previous attempt that got the giant airpocket frozen into it was 404g. If that was filled solid it would probably be 40% heavier. All told, I'd need at least 2500g (actually, bad math I notice now, I calculated as if missing 60%, not 40%, oh well). Turns out I had around 4kg of the stuff, so, should have been plenty even after the excessive dross of melting it in a frying pan.

- A heavy duty stainless steel frying pan is not strong enough to lift 10 lbs of zinc. Had to use pliers on the far side to help

- Missed the sprue, sloshed over into the main pour.

- Zamak is 2.5x the weight of aluminum. Buoyancy on that plaster form is now 2.5x as strong. Up it pops like a cork. Nothing to do but finish the pour and spend 2 hours melting it down again. In retrospect, this is like filling a bathtub and expecting the tennis ball to stay at the bottom.

- Form seemed relatively undamaged by the pour, so for shits and giggles, I stuffed it back in the topside, just guessing at where the center was and the correct angle.

- I hit pretty close to center. I hit pretty close to square to the surface of the pour too... except that the mold wasn't square.

- I probably destroyed the motor bearings, but I lightly hammered the coupler onto the motor, and then pried it back off a half-dozen times. The hardened motor shaft is taking just the slightest shavings off of the surface on a half-dozen splines. It's already 2/3 of the way on, I won't press it further until I have a slide hammer or some way of getting it off, it's too deep into the recess to pry it out if I go deeper.

- Surface of the splines seems as good as they ever were in plaster. Zamak is famed for being a zero-machining process, you can capture the surface of a coin accurately if you want, so all imperfections were silicone/plaster based. It's good enough.

- All the excess chunks I cut off showed solid metal all the way through, no porosity.

- The coupler being off-kilter isn't a big deal. It doesn't have to be a 1/2" thick, and certainly won't be at the transmission end.

Overall, Zamak was beautiful to cast with. Stayed glassy smooth for several minutes (off camera) after the pour. I'll have to keep an eye out at the junkyards for old bathroom fixtures and such.

Plan now is to get the motor spinning, and use it with a grinder as a lathe to make the coupler centered on the motor shaft. Then drill it out for the transmission shaft (a drillbit on a rotating workpiece is self-centering... supposedly).

Also, there's an air cavity at the bottom of the splined area, probably from gas escaping from the plaster. It's not critical, and once I have the hole drilled for the transmission tail shaft, I can gouge the sides and repour some zamak just to give it a helping hand and fill the gap, even if it doesn't add much for strength.

.
 
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