I went to get a nut to mount my original Boyce moto meter to the radiator cap. It looks like the thread is 7/16-27 or an 11mmx1.0. Does anyone know where to get this nut? or what thread actually is?
This prior post has info on the Motometer nut thread.
A lucky T'er got one to fit at a lamp repair shop, those thin nuts used on lamp bases and threaded lamp poles.
This gave me confirmation that size is 7/17-27 and I have ordered a tap.
1/8 pipe thread is 0.405 OD and 27 threads per inch. I think lamp fittings are a straight pipe thread and that's why lamp parts will fit.
Many lamp parts, nuts etc, are a tight fit on the Motometer Junior thread. I have sometimes had reasonable success using a tapered pipe tap to slightly "over-cut" the nut. I never have tried to locate or purchase a proper tap for them.
I have a lamp repair department in my store. I have hundreds of the 1/8 pipe nuts in various thicknesses. I have a Moto Meter collection. I will try some of the nuts and see how they fit. I have a few old stock Moto Meter nuts and I will check as to how they compare.
7/16-27 taps are available from MSC Supply, but not cheap: I don't know if this is Greg's source.
MSC #: 04843223
Thread Size 7/16-27
Class of Fit 3B
Thread Limit H3
Number of Flutes 4
Material High Speed Steel
Show More Details
Big Book: 287
Order Qty of 1 = (1) Piece
Min Qty: 1
Price: $29.86 ea.
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In Stock: 64
I actually found them on EBAY. They varied in price. I bought the cheapest one figuring it would only be needed once or twice, I will make a spare nut so after that it will just sit. Was about $14.00 including shipping.
Greg. i hope you were able to have the same success I was, thanks to the thread mentioned above.
FWIW, Senior size Motometer threads are 5/8-20 on originals.