thank you good man.. i was scratching my head for weeks.

i just started to learn 5axis and my question is how do i edit the post from my z center of the trunion to the top of the part? or do u guys use plane (z .125 + fixture to the top of the part) or edit the post?. ex. if i face top of the part, my post output is z0 but the programmer at my shop post it at 5.1234. i asked him how he did it; he refused to help me by saying " its a secret." background: i went to college and the instrustor did not covered about posting. i bought books from emastercam and it didnt even cover anything about posting. thank you. i would appreciated if u help.