CHAMFER FILE
After surfacing heads, I like to chamfer the bolt holes and chambers. For the bolt holes, the common chamfering tool in a hand drill is great. For chambers, I’ve found that while a razor blade works excellent for aluminum, a file works best for iron. I use a chainsaw sharpening file with the end radiused and polished. This way, if you inadvertently contact a seat with the blunt end, it won’t leave a mark. The same file works excellent for chamfering the bottoms of cylinder bores as well, without the risk of scratching a bore should you slip a little.

Ron Flood
Cedar Machine
North Branch, MN
October, 2022