"das" wrote in message nk.net...
Ahh yes the warm-up period. When I worked at an aerospace contractor all the
union guys wanted to work in grinding or the toolroom. They would get to
work at 6 am, turn on the spindles and go have coffee for 45 minutes so
their machines could "warm up". I think they pushed it just a bit.

Ummm, no. When I was grinding, the machine wouldn't settle down
sometimes for as long as a couple of hours. Not much of a factor on
production, but in a tool room situation where tolerances were
tighter, (much) the variation would have been intolerable. Most
times, minutes saved turned into hours wasted.