cast iron-steel trunnion SawStop PCS

[Bruce Mack]

The Feb. 2010 Woodworker's Journal has a cabinet saw review in which is written about the SawStop Professional "Looking inside, the trunnion assembly is a combination of cast-iron and steel parts. It's lighter in heft than other saw trunnions, but the saw ran as smoothly as heavier-trunnion saws."

Tradional wisdom demands a beefy trunnion. Perhaps this is the advent of higher tech construction, similar to the replacement of cast iron frames in bandsaws. I'd be reluctant to buy one as an early adopter. No vendetta here- I have a Ridgid 3660 and don't do heavy work meriting a cabinet saw.

[Josiah Bartlett]

The only real reason cast iron is traditionally used is that it is cheap to fabricate a strong part with, and the mass gives a side effect of vibration dampening. Steel and other materials can be much stronger with less weight, but tended in the past to be more expensive to fabricate. With the advent of CNC machines and cheap labor in Asia cast iron isn't always the optimum solution any more.

[Paul Ryan]

The only advantages that I can think cast iron would bring would be more mass/weight for vibration dampening, and lower cost. Steel will last longer and is stronger than cast because it isn't brittle. I think an entire trunion system out of a good quality steel would be the cat's rearend. But it would be expensive. Look at crankshafts in internal combustion engines. A steel/forged crank shaft is much stronger than a cast crank, but is much more expensive.