I learnt a Bridgeport specific lesson yesterday, it was free too
Spent an hour trying to figure out why my G55 offset I had set up for a groove in my almost permanently mounted vise had shifted about 50mm in the Y. Totally stumped, tested it, tried adding new offsets, these all worked, co-ax indicator on a mounted shaft showed 53mm shift in Y only
It wasn't until the penny dropped that i remembered sliding the ram out to get a better position in readiness to machine my sub-table - D'oh!
So, that got me thinking, offsets are pretty much useless on a flexible machine like the Bridgeport - any movements in the head will instantly wipe out all offsets saved and if not remembered, could be expensive in bent tooling.
The one that WILL bite me is the semi-auto manual tool change on the engraving head - this uses a fixed touch-plate to gain the height offset and its location is stored in the setup pages.
Need to put a large sign on the head-shift bolts i think.