engineering questions

["Watry, Andrew" <Andrew.Watry@domain.elided>]

Two engineering/manufacturing questions not directly related to Alfas:

1.  What is "friction welding" and how does it work?  I've heard Porsche or
BMW uses this method in making wheels.
2.  Some modern connecting rods are made as one piece, then fractured in
half to allow for the split to assemble around the crank journal.  How do
they keep the fracture precise?

Thanks
Andrew Watry

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