what does 1 2 x 28 tpi mean?
Joined: Dec 24, 2002 Messages: 27,103. To be more specific, 1/2 x 28 means 28 threads per half inch. To be correct, 1/2 x 28 means half inch diameter, 28 threads per inch. You would think a 13mm would be the major diameter over the threads, about .