My car ('73 TC) has 70's era Appliance wheels. I broke one of the nuts, as the clearance between the extended shaft of the nut and the wheel is near zero, and I wasn't aware of the potential problem. It was binding, and I just broke off the shaft. Jeez!
After some research and contacts with a number of people selling 'wheel accessories' (nuts and the like), including some that specialize in vintage wheels, it seems that a similar nut is not obtainable.
I've learned that wheel nuts and studs are surprisingly non-standard, with many sizes being used.
I'm thinking that I'll make the holes in the wheel a 60 degree taper to accept more common nuts. Not many nuts are made in the 3/8-24 size any longer that are the standard for the Europa hubs. I did get some nuts made for use on ATVs that are that thread specification though.
There are nuts of this "mag wheel" type (not tapered, with an extended shaft) in that 3/8-24 size intended for Minilites and similar for Minis, Spitfires and MGs. But they all have larger diameter shafts rather than the .520 that my wheels have. I'm more inclined to make my existing holes tapered rather than make them larger.
I might want to go to a more common 12mm x 1.5 thread stud in the future, and tapering the holes shouldn't cause any problem with that I believe.
As I assess things, I think that my studs are actually too short for these wheels. Just not enough thread engagement, so that's another thing that leads me to think that a new, more modern, thread size would make sense if I should get new studs anyway. The wheel/hub mating surface is .600 thick, much thicker than that of the original steel wheels, and whoever put these on the car apparently didn't give any thought about that. But going to a tapered nut and getting rid of the washer that is part of the old nut will give more thread engagement on the existing studs.
So is there any good reason why I shouldn't modify the wheels to take a tapered nut? Your thoughts would be appreciated! I'm ready to do it, but can't 'pull the trigger' until I'm without any serious doubt.
I may get new wheels down the road, but it's not a priority. There's lots to check out and improve upon, without taking on that expense.
Some pictures follow. One shows the broken lug nut next to an unbroken one, and another shows the proposed replacement alongside the 60 degree countersink bit i would use to make the taper.
Thanks,
Vince