Stocks like Rexnord (RXN) and Colfax have become key cogs in the machinery sector. Those and other strong names were already working on ways to boost productivity before 2008. The great recession forced them to ramp up those initiatives as well as squeeze costs. “Once the 2008-09 crisis was past, a lot of companies began to fill their production capacity, fill their factories,” said David Rose, an analyst for Wedbush Securities.