I accept that modern cranks are made of malleable or SG Iron - but I was
fascinated to see a RR Merlin crankshaft forging die and forging at a
museum in Sheffield, They were forged with the cranks in one plane - then
a twist was applied to each web to give the angular relationship - then
machined. Amazing.


Photo of RR Merlin forged and twisted crank - with forging die - all in one
plane

http://picasaweb.google.com/lh/photo...tXF8v8Y0cKFi7Q