Taps and dies

[Grant Bowker]

I'm glad we've returned to the original pont of the thread.
Threads, taps and dies.
I assume you've sought out tables of the diameters and threads per inch for the various threading standards. BSF, SAE fine and coarse, whitworth etc are all decribed on the net. Most of the standards are different enough that careful measurement will let you tell which set of threads your example fits into. I would be surprised if there were a metric thread on a carrier so that should narrow the field a bit. Normally for the larger threads like yours I actually count the number of threads in an inch rather than measuring one pitch and taking the inverse, it reduces the number of ways I can get it wrong. Measuring outside to outside on the male thread is usually close, but a bit smaller than the thread size. On Chev CMP trucks I don't recall meeting any bolts that had to be measured to 1/32 inch, I think 1/16 is the smallest step between sizes. Anything is possible but unless there is a special need I think they would have stayed with similar increments as "standard" practice on carriers. Be cautious on how much of what I said above you take as gospel I don't actually have a carrier for experience.