What is the thread for the steering wheel nut.

[Stew Robertson]

Pipe thread is tapered
The thread in the nut can be turned on a lathe then the cap tig welded on to match the under cut in the nut
clean up, the welds and presto you have a steering wheel nut almost original
or maybe it is
the cap is a piece of light gauge metal like a frost plug

[Lynn Eades]

3/4 NPT is only 14 tpi. It will be 3/4 U.N.F. (16 tpi)
When quoting U.N.F. or U.N.C. it is not required to quote the inclusive angle of the thread. They are all 60 degrees while the standard British threads are 55 degrees.

[rob love]

Originally Posted by Stew Robertson

Pipe thread is tapered

Not quite true. NPT (National Pipe Tapered) is tapered, NPS (National Pipe Straight) is straight.

[ajmac]

Standard BSP is a straight thread too, it seals on a copper or dowty washer rather than on the threads like NPT.

[Paul Dutton]

Originally Posted by ajmac

Standard BSP is a straight thread too, it seals on a copper or dowty washer rather than on the threads like NPT.

Or WD seal.

[Stew Robertson]

That is the point I was making pipe thread is Tapered the nut is not and the threads are a standard 29 1/2 degree thread at 16 tpi and can easily be turned on a lathe with the cap tig welded on so the thread can have the under under the cap
Clear as mud

[Stew Robertson]

hi Lynn I was taught from way back when you always set the compound rest at 29 1/2 to cut the standard Canadian thread but Canadians are always a little behind ,but not down under

[Lynn Eades]

Stew, that went straight over the top. I'll have to stand up next time. (the cricket people would say "it went straight through to the keeper")
I do have a small lathe, but powered thread cutting is not something that I can do on it. (I would figure it out if I had to) Obviously my skills in the machine shop, are not up with yours.
I do use it to get the die holder square.