Bridgeport Ways Question

[turbotadd]

Richard mentioned a while back something about Bridgeports having thinner, lighter castings during a certain era (presumably for cost savings). This got me thinking about the Bridgeport I have at work and I noticed one day that the flat ways on the top of the knee look like they have milling cutter marks along with the half-moons. Did Bridgeport ever rely on just milling and flaking the ways for cost savings?

 

[4GSR]

Could be grinding marks from using a cup wheel. I worked on a Bridgeport back in the late 1970's that had chrome ways on the knee. It was still new enough to see machining marks on the ways, but I almost guess it was grinding marks. Maybe someone else out there can shed some light on the subject.

 

[Richard King]

Those Bridgeport's were lighter when Textron bought them. That's when the top of the base is flat and not concave...or to hold the coolant and they took away the door on the side where people would store things or that's where the coolant pump was suppose to go. As far as the cup marks, 4 gsr could be right, but I have never seen on from the factory that way. Ed Hadley a retired rebuilder here in MN used to rebuild his machines that way. He specialized in Bridgeport's and I would bet he turned out 2 or 3 machines per week for 30 years plus other machinery. He had several old planners dedicated to one part of; Knee, column, saddle, table plus he had a surface grinder to do the table tops. We used cup wheels on those planers mounted in Bridgeport heads.

UPDATE: Sat. Jan 5th. I was talking to Ron DeWalt another machine rebuilder here in MN yesterday and asked him if he had even seen a Bridgeport with spiral grind marks on the Knee before? He couldn't recall that before either. We both agreed it must have been rebuilt.