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Stainless Steel Fords

I hadn’t heard of these, DeLorean had nothing on 'em:

The writer is confused. Keeps implying these cars are heavier than ordinary carbon steel. They aren’t. The weight of stainless steel is virtually the same as regular sheet steel.

I saw one of the 36s at the Crawford Museum in Cleveland. Pretty cool looking car.

The thickness of the metal might make the stainless heavier. It isn’t as stiff as the real steel and might need more bulk to maintain strength. It has advantages like being easy to bend and it’s hard to get it to crack. It won’t corrode as fast as the other stuff is known to.

Exactly. Stainless steel isn’t as strong as carbon steel, so they may have had to use a heavier gauge for the same strength.

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C’mon now. You do realize that there are different hardness possibilities for both materials right? I have some stainless sheet metal I can give you that you cannot cut without a torch. If you try bending it (good luck) it will fracture easily. I also have some stainless sheet stock that is very soft in comparison and will bend and cut easily. The same is true for any steel or other alloy of metal…

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There are many ways to gauge “strength”. Ask any mechanical engineer- how strong is this material? After they stop chuckling, they will ask in what way you intend to use it and then tell you if it is “strong” enough for that purpose…

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I imagine that a low carbon 300 series steel was used for the Ford auto bodies. Stainless steel hardens more quickly when cold worked than plain low carbon steel used in auto bodies.

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Young’s Modulus, or the measure of stiffness, is virtually the same as low and medium carbon steel.

The strength, however, as @TwinTurbo points out, depends on the grade of stainless steel used. You want a 300 series stainless for corrosion protection so I’d guess 304 sheet might be appropriate. 304’s work-hardening rate is higher, as @jtsanders points out, than low carbon sheet steel so the finished product would have roughly the same yield strength if not higher. But it wouldn’t weigh any more.

I’d guess they just ran sheet stainless of the same thickness in the regular Ford dies and picked the best of the lot to build the cars. It was a learning experience for all involved.

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I suspect the weight comment was because there’s a stereotype that all old cars weigh eleventy-billion pounds, especially since they were all metal rather than some metal next to polyurethane/fiberglass/carbon fiber panels.

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eleventy-billion

Do I hear Spongebob coming through in your reply :grin:

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Maybe? I’ve never actually seen the show! For me it’s more an adaption of a Hobbit quote - Bilbo’s “eleventy-first birthday.” :wink:

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I think they had an eleventy seventh anniversary on SBSP. I am subjected to it on a regular basis. They mimic a lot of stuff from elsewhere so maybe this is one of those instances.

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Churchy used 'lebenty often in Pogo.

From Hemmings: “both the Thunderbirds and the Continentals somehow ended up weighing about the same as their production counterparts. (According to Frank Scheidt of the Early Ford V-8 Foundation, the stainless 1936 Ford weighs anywhere from a couple hundred pounds to 500 pounds more than a comparable production 1936 Ford.)” Full article below…

https://www.hemmings.com/stories/2020/05/21/full-set-of-allegheny-ludlum-stainless-steel-bodied-fords-put-up-for-sale-by-the-company-that-built-them?refer=news&utm_source=edaily&utm_medium=email&utm_campaign=2020-05-24

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I read an article about these a long time ago. Ford had a hell of a time making that Stainless do what they wanted it to do. It all revolved around the work hardening that would take place…as others have pointed out.

I still have that magazine somewhere, derned if I know which one that article resides in however.

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Back in the 1930’s there weren’t stamping presses strong enough to stamp out an entire roof panel from mild steel sheet. That’s why they had fabric inserts. Not surprised pounding out those curves was very difficult for them. As @Honda-Blackbird pointed out, stainless work hardens faster than mild steel so the deeper the draw, the harder it gets. I’d guess the die material was not as strong either.

One of the reasons the Tesla pickup looks like it was styled with only a ruler and made just with a press brake, I guess.

Think back to the DeLorean… relatively flat panels and press brake bends!

Flat panels “drum” or “oil can” like mad. Ya need a little curve to stiffen things up. Maybe Tesla designers forgot that.