Does anyone know the thread used on the inner tube valve, the thread that holds it to the rim?...At first sight it looks like it may be 5/16" x 32 tpi Model Engineers thread...(this was also used in instruments etc., not just in model engineering...)...
:sunglasses: Ha, Ha, far from it...I want to make a few of the old style fasteners that hold the valve in place...Round brass, straight cut knurled edge etc...I'm not keen on the nuts fitted to modern tubes...Ian
I can get a carbon steel tap for £15 which may be adequate for tapping into brass...However, first it's going to be a trawl through the internet to try and find a better deal on a HSS item...
I have many, many taps and dies but I never quite seem to have them all...I've needed another unusual one in the last month...27 tpi ANF (for a Triumph oil pressure switch blanking plug)...Ian
I seem to remember a 32tpi among a load of taps and dies that I acquired off a mate. I'll look through them later when I get back from Kempton Park. Ron
As Ron explained already, I've made a pair of these nuts for my WD/C, and I used a 5/16 32TPI ME tap. A few tenths of a millimeter too large I admit, but nobody will ever notice... :innocent:
PS. Just checked through my 32 tpi taps. All I have is .45" 1/4" .22474" and another small 5 figure size that I can't read. Some strange sizes, obviously for special jobs by a precision engineering firm?? Ron
Wouldn't it be quite easy just to make a tap for that Ian?
5/16 silver steel, turn down and thread it male, grind 3 flutes into it and then cherry red heat to quench in oil.
I have done it many times to get an odd thread sorted and it works really well. A 55 degree point on a small hss tool is all that required for the screw cut.
Now it's not that I am frugal, I just like solving puzzles like that as an old friend says, if the sub is stuck on the bottom, failure is not an option.
Darren
