Send them all to me and let me figure them out !!!!! :biggrin::wink:
You could do a trial in a piece of scrap to determine whether it's triple, double, or single ... examine the threads and count the starts.
There is some useful info on the web about distinguishing the tap types ... I'll see if I can find it again.
Here it is:
http://www.newmantools.com/taps/taptech.htm
[FONT=HELVETICA, VERDANA, ARIAL][SIZE=-1]The kind of hole to be tapped has much to do with the style of tap that's best suited. Some holes go all the way through. Others, while not throughholes, still are relatively deep. Some are quite shallow, little deeper than diameter. Each of these three kinds of holes through, deep-bottoming blind, and shallow bottoming, has a tap or group of taps best suited to requirements.
Taper Taps have 7 to 10 thread chamfers to distribute cutting action over many teeth and the taper also acts as a guide in starting.
Plug Taps, with a chamfer over four threads, is most widely used in through holes and where there is sufficient room at the bottom in blind holes.
Bottoming Taps are made with just enough chamfer for starting in the hole, only 1 to 2 half threads. As the name implies, it is designed to thread blind holes to the bottom.
And also Wikipedia:
[/SIZE][/FONT]Bottoming
tap or plug
tap. The
tap illustrated in the top of the image has a continuous cutting edge with almost no
taper — between 1 and 1.5 threads of
taper is typical. This feature enables a bottoming
tap to cut threads to the bottom of a blind hole.
Tap and die - Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Tap_and_die