A HOT CUTTER CAM
I always like to test fit the camshaft before assembling an engine I have machined. We have all seen camshafts that do not fit well in the cam bearings. Most of us have had to make a “cutter camshaft” by cutting sharp slots in the cam journals of an old un- wanted cam to rotate in the cam tunnel to relief cut the new cam bearings. Lately, I have seen a lot of camshafts that have journals finished a few tenths larger than the O.E.M. spec. This makes a difficult job of relief cutting the cam tunnel for the new cam because the used OEM cam is often smaller than the new camshaft. When I encounter this problem I put the cutter cam in my hot tank for 5-10 minutes to get it good and hot. I pull it out of the hot tank quickly and cut the cam tunnel while the cutter cam is hot and expanded from the heat.

Dave Matton
D and D Auto Machine,
Bloomington, MN
July, 2016