flat plane crank

[joyridin']

Originally Posted by wkooiman

Forging consists of dies that force the steel together, much like you mash snow together to make a stronger snowball. A 90-degree crankshaft would consist of a complicated set of dies, just to get the crank out of the dies after forging. It is simpler to have 2 dies that forge in 1 plane, and then after the crank is removed, the crank is twisted into the correct orientation while the steel is still malleable.

There are non-twist forged cranks, but they are surely more expensive, and the cranks from the 60's were surely all twist forged.

You can google this, and find sites that explain it better.

Ok...I have never seen a twist forging. I visit a couple places that manufacture cranks and none of them use this method. Thanks!

[LoBelly]

Originally Posted by joyridin'

Ok...I have never seen a twist forging. I visit a couple places that manufacture cranks and none of them use this method. Thanks!

had never considered that the cranks might have been twisted into shape...



LB