Steel as a homebuilt material ?

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cheapracer

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Speedboat100

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Speedboat100

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Yes.......https://www.quora.com/Is-steel-or-titanium-more-expensive


100 x more expensive than steel.....the titanium is.
 

cluttonfred

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For a different way to look at using steel in aircraft construction, consider the late-WWII designs by Richard Vogt such as the Blohm & Voss BV P.211.02 Luft '46 Entry (image from same source). The plane never flew, but many of the structural components were built for testing so you can see how it went together.

An emergency jet fighter is obviously a very different animal than a sport aircraft, but the concept of using rugged, low-cost steel sheet for a primary structural backbone (the dark gray component that goes from nose to tail) and lighter materials like wood, aluminum, and fabric for the rest could still have merit.

It's not hard to imagine a structure like a Hovey Whing Ding fuselage made of mild steel sheet to which seat and harness, engine, wings, tail boom, and landing gear all attach. With the right software to optimize the structure and a plasma CNC set up, all the appropriate lightening holes could be pre-cut and the weight could be manageable.
 
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Jimstix

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The real issue with thin SS sheets is buckling. The Budd Conestoga has very closely spaced skin stiffeners and zillions of closely pitched spot welds. They made it work but it looks terrible - lots of skin wrinkles. (Go see for yourself at the Pima Air Museum). Pound for pound wood (plywood) is much more resistant to to buckling because of it's thickness.
 

galapoola

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Whenever I've seen/read about a fabric wing being "metalized" it is aluminum over aluminum. Never seen aluminum over wood. After reading this thread it got me thinking about how a wing design is either very rigid or meant to flex. I've given some thought to how it would be possible to recover a rag wing in aluminum, one that is all wood underneath. The only reason being to survive sitting outdoors. I was always thinking it couldn't be done because wood and aluminum expand and contract with temperature differently and things would work loose. Now I'm wondering if the flexing/stiffness characteristics are more the reason.
 

Speedboat100

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Whenever I've seen/read about a fabric wing being "metalized" it is aluminum over aluminum. Never seen aluminum over wood. After reading this thread it got me thinking about how a wing design is either very rigid or meant to flex. I've given some thought to how it would be possible to recover a rag wing in aluminum, one that is all wood underneath. The only reason being to survive sitting outdoors. I was always thinking it couldn't be done because wood and aluminum expand and contract with temperature differently and things would work loose. Now I'm wondering if the flexing/stiffness characteristics are more the reason.
Wasn't the Hughes H-1 replica metal over wood ?

 
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BJC

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I've given some thought to how it would be possible to recover a rag wing in aluminum, one that is all wood underneath.
It is difficult to rib-stitch through aluminum. And bonding aluminum to wood is problematic, as you have noted. (Not to mention the difficulty of bonding anything to flexible aluminum sheet.)

... wood and aluminum expand and contract with temperature differently and things would work loose.

BJC
 

galapoola

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Instead of bonding, aluminum screws instead of rivets. Holes in wood match drilled, dab of glue or epoxy on the thread and attach.
 

Dan Thomas

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Whenever I've seen/read about a fabric wing being "metalized" it is aluminum over aluminum. Never seen aluminum over wood. After reading this thread it got me thinking about how a wing design is either very rigid or meant to flex. I've given some thought to how it would be possible to recover a rag wing in aluminum, one that is all wood underneath. The only reason being to survive sitting outdoors. I was always thinking it couldn't be done because wood and aluminum expand and contract with temperature differently and things would work loose. Now I'm wondering if the flexing/stiffness characteristics are more the reason.
Yes, the differential in the coefficients of linear thermal expansion causes immense problems, and not just with wood attached to aluminum. I did the installation of a converted Subaru in a Glastar, and that airplane had a plexiglass windshield bonded to the fiberglass fuselage. The windshield cracked in the cold weather, since plain plastics shrink a lot more than glass-reinforced plastics.

And the aluminum wing skin will much more quickly form condensation on its interior at night, as radiative cooling causes metals to cool much faster than fabric or wood. You can see the difference when you see condensation inside the roof of an uninsulated metal hangar; you don't see that in an uninsulated wooden hangar. Stuff rusts in a tin garden shed, not so much in a wooden shed. Condensation inside a metal skin won't do the wooden spars or ribs any good at all.
 

BBerson

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Ken Champion (1960‘s) made translucent fiberglass skins for his wood wings on the "Jupiter". . Easy to see the bond.
 

thjakits

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It's really a matter of size!
Once you get to a size where you can use your chosen material in a way it shows desired properties - you are there!
SpaceX - SS/SH - they can use 2mm and 3mm Stainless and its stable - it doesn't wobble and ripple when built up.

Thinking you can use a 0.02mm FOIL for anything but in none stressed applications in a small airplane - ...think again!
I would believe when you get to the size of a Roe Princess or a little bigger - you MIGHT get away with steel...

As a structural material (frames, connectors, etc..) it is well known, still - detailed calculation is required to not make things too heavy...

Even in a sandwich a 0.02mm foil is too thin - any little scratch goes right through to the honeycomb material...

thjakits
 

BBerson

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The real issue with thin SS sheets is buckling. The Budd Conestoga has very closely spaced skin stiffeners and zillions of closely pitched spot welds. They made it work but it looks terrible - lots of skin wrinkles. (Go see for yourself at the Pima Air Museum). Pound for pound wood (plywood) is much more resistant to to buckling because of it's thickness.
Might look terrible, but structurally sound. Essentially a buckled Wagner tension web structure.
I think .010" SS is about what they used. Same weight as .030" aluminum but easily spot welded.
 

Speedboat100

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How thick would the aviation-steel have to be in order to stay sorta handleable ? SpaceX thinnest is 2 mm.
 
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