Clocking

[i2i]

there was probably a match on, that's why the traffic was bad. Give me a ring anytime and i'll explain it for you.

[AdieR]

Clocking: refers to the use of a Dial Test Indicator (also sometimes abbreviated to DTI, or referred to as a "clock" or "clock gauge", hence the term "clocking").

For example, to "clock a vice" on a milling machine: set the vice up approximately with the T-slots on the machine table and *gently* tighten the nuts (not fully, you'll need it to move slightly). Lightly trap a parallel in the vice.
Using a DTI / clock (or whatever you like to call it), set a zero on it with the DTI "finger" at one end of the parallel, then wind the table across so your gauge ends up at the other end (still with me?) and record the error. If required, GENTLY tap that end of the vice away from the DTI finger, by about half of the error (ie, if you have an error of 0.2mm, tap the vice until you get about 0.1mm reading).

Repeat this process until you get minimum or zero error (if you get a zero error reading, make sure the finger is still in contact with the parallel).

Your vice is then "clocked", ie it is aligned with the machine table, and you can now set up your workpiece in the vice.

Yell if you're struggling with my explanation - it's a difficult subject to explain in words: it's far easier if you can get someone to show you to be honest.

Hope that helps.