on a TAP & DIE set, how do I read the numbers printed on the taps and dies?

Answer 1

Check this site; will answer your questions

http://www.sizes.com/tools/thread_screw.htm

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Answer 2

What do you mean how do you read them.I guess you have to put your glasses on.If you would like to know what your reading means i can help you with that.If you pick a tap up and look on the side it will read 1/2-13.What that means is its 1/2" bolt size and 13 threads per inch.which is standard for a 1/2"bolt.Some tap and die sets also tell you size of hole to drill before you tap the hole.I"ve always used the 1/16" method.In other words if i was going to tap a 1/2-13 thread id drill a 7/16" hole.If you use a 1/2-13 tap that means a standard 1/2" bolt will fit in the hole.

Answer 3

The fractional number is the size, ie: 1/4, 1/2 etc. or in millimeters, 10, 12, 13. The other number is what is called the "pitch", thats is how many threads per inch or centimeter.
the higher the number the LESS pitch, them more threads per inch. So 24 pitch is 24 threads per inch where as 18 pitch is 18 threads per inch which is corser and more "pitched" or angled as it were.