4140 steel as a one piece crankshaft

[bazmak]

The sx2 with fixed column is rigid its the swivel column and bellmouth washer that causes all the problems

 

[Parksy]

I have the swivel version. I need to modify it and fill the column with some weight.

 

[Fluffy]

Andy,
The aluminium is there to stop the crankshaft flexing about the crankpin when turning the journals. All turning done after the crankpin was completed was with HSS tooling with high rake angles to reduce the cutting forces.
Regards,
Don.