Gravity bends a crank?

[V8COOPMAN]

Originally Posted by tubman

I have always been amazed at discussions like this. Here's a crankshaft that can take the firing impulses running in an engine for 90-100K miles, and some prople wwill think it will bend sitting on a floor? Give me a break!

Soooo, are ya saying cranks don't twist with each firing impulse? There's a difference between "bend", "twist" and "yield point". You ever think about what a harmonic balancer does in conjunction with a crank? DD

[FrankWest]

Originally Posted by tubman

I have always been amazed at discussions like this. Here's a crankshaft that can take the firing impulses running in an engine for 90-100K miles, and some prople wwill think it will bend sitting on a floor? Give me a break!

Gravity is considerably weaker than the forces that hold matter together. The nuclear force being the greatest. You would think the bonds of the molecules in the metal would be many orders of magnitude greater than the pull of gravity on a small tab.
Perhaps it the tab was over a foot then with time it could sag under its weight, and long distance to its connection to the shaft!

[rowens55]

Originally Posted by FrankWest

Gravity is considerably weaker than the forces that hold matter together. The nuclear force being the greatest. You would think the bonds of the molecules in the metal would be many orders of magnitude greater than the pull of gravity on a small tab.
Perhaps it the tab was over a foot then with time it could sag under its weight, and long distance to its connection to the shaft!

Man, you fellers is SMART !!!! By th way, what's a "molyquals"?

[bbrocksr]

Originally Posted by tubman

I have always been amazed at discussions like this. Here's a crankshaft that can take the firing impulses running in an engine for 90-100K miles, and some prople wwill think it will bend sitting on a floor? Give me a break!

Cast iron cranks will definitely sag if stored horizontally and not supported correctly! The longer and heavier they are the more apt they are to sag. If you don't believe it you just haven't experienced it yet.
A Model A crank which is shorter, lighter and made of steel is not so apt to sag if stored horizontally.
Bill

[rheltzel]

Originally Posted by bbrocksr

Cast iron cranks will definitely sag if stored horizontally and not supported correctly! The longer and heavier they are the more apt they are to sag. If you don't believe it you just haven't experienced it yet.
A Model A crank which is shorter, lighter and made of steel is not so apt to sag if stored horizontally.
Bill

And you base this assertion on what empirical evidence?

[bbrocksr]

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Originally Posted by rheltzel

And you base this assertion on what empirical evidence?

Sixty three years actual experience building engines, from flatheads to diesel engines and aircraft engines.

How about your actual engine building experience?
Bill

[rheltzel]

Molly Cules...she worked at the cafeteria next to the crankshaft foundry at the Rouge plant. Was said to have inspired the workers to make sure their crankshafts were always straight, even if they were laid flat.

[rowens55]

Originally Posted by rheltzel

Molly Cules...she worked at the cafeteria next to the crankshaft foundry at the Rouge plant. Was said to have inspired the workers to make sure their crankshafts were always straight, even if they were laid flat.

HAHAHAHAHAHAHAHAHAHA-puke-HAHAHAHAHAHAHA

[5851a]

I feel better storing a crank laying on the floor, if I store anything standing up I'll knock it over before I get around to using it.

[FrankWest]

Originally Posted by 5851a

I feel better storing a crank laying on the floor, if I store anything standing up I'll knock it over before I get around to using it.

True, if you store it balanced on edge it may fall over and break something.

[Marv]

Originally Posted by rheltzel

Molly Cules...she worked at the cafeteria next to the crankshaft foundry at the Rouge plant. Was said to have inspired the workers to make sure their crankshafts were always straight, even if they were laid flat.

Now this i can believe.

[Lincoln]

My previous employer, who manufactured medium-to-large industrial stationary type engines (up to 30,000 horsepower), had a policy to always store their crankshafts vertically as lying them down would "permanently" distort the throws even with the main bearing surfaces supported properly. So they were stored vertically with the flange end supporting it. No doubt the design and length of the crankthrows, between the mains, contributed to the flexibility of the shaft. These were one-piece forged steel crankshafts and could stand up under the rigors of almost continuous operation for many years, but they had to meet certain requirements on what was termed "crankshaft web deflections". Service conditions as well as how they were stored all affected "deflections".
Considering the shortness, and "apparent stiffness", of the Ford's crankshafts, I would not think method of storing would be important - as long as they were stored without supporting something heavy!

[itslow]

Originally Posted by Lincoln

My previous employer, who manufactured medium-to-large industrial stationary type engines (up to 30,000 horsepower), had a policy to always store their crankshafts vertically as lying them down would "permanently" distort the throws even with the main bearing surfaces supported properly. So they were stored vertically with the flange end supporting it...

How were the counterweights and journals supported when stored in the vertical orientation?

Without additional support the counterweights and journals will still have a bending moment imparted upon them when stored vertically. This would have a cumulative effect as you move down the crankshaft towards the ground (assuming they were stored sitting on a surface instead of hanging).

[ford38v8]

If she's the same Molly I once knew, she personally bent many a shaft in her time.

[FrankWest]

Originally Posted by ford38v8

If she's the same Molly I once knew, she personally bent many a shaft in her time.

In the scifi film Forbidden Planet several space ship engineers were commenting on a new piece of scientific equiptment and one said,
I bet every Quantum Mechanic in the force would love to get his hand on this!
Funny

[glennsanders]

Know that's some funny stuff that there is.

[FrankWest]

Still many strange and unknown things exist. Maybe there is an unknown property of the metal in the crank that could create some strange phenomena so you better store your your crank in the vertical position just to be safe. After all, science for over a hundred years could not account for the fact that bumble bees can fly because their wings are too stubby to lift their big body aerodynamically...
But with recently with ultra high speed photography they found that the bumble bee does not flap his wings up and down as previously thought but rather front to back. So aerodynamically the bumble bee should not be able to fly but accounting for fluid flow dynamics of air with front to back flapping, more lift is actually generated. Maybe some day aircfaft designers will employ this principle to generate aircraft with greater lifting capacities.

[rheltzel]

At the risk of getting serious, years ago my buddies and I bought a NOS 99A crankshaft from the Ford dealer in Pinedale, WY. It was in a wooden shipping box which obviously was intended to be shipped and stored in a horizontal position, suggesting Ford wasn't very concerned about the effect of gravity on its famously stout crankshafts.

[40cpe]

In the past a picture was posted here on the 'Barn showing a rack that would hang the crank by it's flange. Do you s'pose they will stretch?

[my4dv8]

So it's true if you lave a crank laying on its side long enough it will eventually turn into flat steel plate as it succumbs to the evil forces of gravity. I stand mine up cos it's more convenient.