I want to attach a cam that is 1" wide, 2.5" dia and attach it to a 1" x 1' hard shaft. This will replace a cold-roll shaft that is failing due to poor design. (mine) It runs at 100 rpm in 2" of needle bearings and under high pressure from the cam. The original is taper pinned and shrink fit, it's not going to move on that shaft. The cam is full hard O-1. With the cold-roll shaft getting eaten by the needle bearings, I have about a month before melt-down to come up with a cure. I'm thinking of a hard shaft in the bearings or sleeve the cold-roll shaft with a 1-1/4" inner race and boring out the needle bearing housing to accommodate bigger bearings. There's not a lot of room to do this but it will accommodate a 1-5/8 OD bore leaving 1/16" of meat around the bearing in two spots in the rectangular bearing holder block.
If I go with the hard shaft, what's the best way to attach the cam? (forever) I'll make a new cam for it. Would Thompson shaft be best?