Joined: Jan 2010
Posts: 9,779
Likes: 1,747
From: Northern California
Bikes: Cheltenham-Pedersen racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.
The only alternate axle threadings I've seen are Campag's 26tpi and the even much-finer threaded axles used on high-end Maillard-built hubs branded as Maillard, Edco and Roval.
Finer threads result in a stronger axle because the shallower threads preserve cross-sectional minimum diameter while also reducing stress concentration factor.