The crankshaft was made from separate pieces, silver soldered together, and then the throw was sawed out.
Sawing out the crankshaft web. The Buehler slow speed saw makes operations like this a breeze, and very accurate, since the positioning is done with a built-in Starett Micrometer. This saw was gotten for nothing - I never would have paid the going price for one. The Crankshaft, after sawing and some polishing is on the right.