Dropped axle

Shaping such an axle by sawing or cutting would place an area of cross-grain across the upright part and would rapidly break.

As cars increased in speed after World War I, the use of a dropped front beam axle became almost universal, so as to lower the mass of their heavy front-mounted engines, improving stability when cornering.

Axles were made of drop-forged H girder sections, so forging their upswept ends was a simple addition.

To avoid creating stress risers, the drop was formed as smooth curves, not as sharp corners.

Bugatti famously used a round bar for their axles, with the spring passing through holes within it and avoiding the U bolts that il patron found so ungainly.