I am not a huge fan of using a taper sine block to measure the pitch diamter on a tapered thread. Why? Because you are basing your measurements on an assumption.
Measuring with the taper sine block give you the small end P.D. Lovely.
The important part of the taper is at the notch. Of course, you can do the math and calculate your P.D. at the notch- but that math is ASSUMING that the taper of the thread is 0.0625 EXACTLY. It could be 0.0005 in either direction, or completely made wrong. Of course, you can take a measurement at the small end and the notch and incorporate the difference into your calculations, but I still don't like that.
I prefer a functional check using a master gage.
To the OP- if you like, I have a nice little Excel spreadsheet I can send you that does the math for you. PM me.
Measuring with the taper sine block give you the small end P.D. Lovely.
The important part of the taper is at the notch. Of course, you can do the math and calculate your P.D. at the notch- but that math is ASSUMING that the taper of the thread is 0.0625 EXACTLY. It could be 0.0005 in either direction, or completely made wrong. Of course, you can take a measurement at the small end and the notch and incorporate the difference into your calculations, but I still don't like that.
I prefer a functional check using a master gage.
To the OP- if you like, I have a nice little Excel spreadsheet I can send you that does the math for you. PM me.