I just did a search on "Bolt Size Chart" and there are plenty that will answer your question.
Don Dando
Thanks. Got a lot of info on the original post. Metric is a lot easier .
Gee, here I thought that everybody knew that a 10-24 bolt has a 3/16 inch shank with 24 threads per inch. Jim
But not everybody lives in America and lives by their rules.
Well having grown up around BSW/BSW/UNC/UNF/BA *and* Metric I for one knew the 24 was the tpi but I didn't have a clue and still don't as to what the 10 means.
From what you say It's clearly not 10/64" or 10/32" or 10/16" 10/8" or
10/4"10 gauge(swg) is about 3.2mm or just over 1/8" so its not that either
10 gauge (awg) is 0.1019" so its not that, nor is it 10 gauge (shotgun) as that is 0.777 inchesAnd some say metric is complicated?
10 is just another arbitrary number someone picked out for the diameter. It probably starts at 0 or maybe even 00. I know model trains use a lot of #2-56.. #4-40 is pretty common as the size in a D shell connector retaining screw and orher small machine screws. #6-32, 8-32 and 10-32 are the most commonly used small machine screws. 10-24 is more of a "stove bolt" kind of thing with a course thread used in places where fine tolerances are not required and where it may be dirty when you install it. If you had a jar of 4-40s. 6-32, 8-32, 10-32 and 10-24 it would be about all you would need until you get up into "bolt" sizes like the 1/4"x20 and up.
Americans experienced the same problems from lack of thread standardization that Britain did. The challenge was taken up by William Sellers, scion of an eminent family of American "mechanicians," whose grandfather had made the plates with which the Continental Congress printed its currrency. In 1864, a committee of the Franklin Institute recommended the adoption of Seller's system of screw threads. The thread form became known as the "Franklin thread," or, more commonly "Seller's thread," and later as the "United States Standard Thread." It became the basis of the French standard thread, and then of the Syst=E8me International thread. In May 1924 it was designated the "American Standard Thread." In 1907 the American Society of Mechanical Engineers (ASME) defined two series that used Seller's thread, numbering the sizes by gage numbers from 0 to 30. In the series the major diameter started at 0.060 and increased by 0.013 inch with each size from 0 to 10, and by 0.026 inch between gages above #10. Shamelessly cribbed from
So number 10 is 0.060" + 10 x 0.013" or 0.190", about 3/16" ie.
0=2E1875".Interestingly enough, modern screw charts show #12 as 0.216 and #14 as
0=2E242 which means that at some point after 1907 the 0.026" increment was dropped and 0.013" used above #10 too: #10--0.190, #11--0.203, #12--0.216, #13--0.229, #14--0.242HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.