I just got a job to make some head plates for a Cummins in-line 6 diesel engine. There are 3 holes that I have to machine that match up with dow pins that stick out of the top of the engine block. He INSISTS that these holes are bored out using a boring bar.
On the same note, I have a 2011 HAAS VF-3 that will interpolate an endmill with a finish tool/pass to meet tolerances easily of plus or minus .0005". The tolerance he is expecting is .6325 plus or minus half a thou. Material is H13. Thickness is under an inch. I am good at making sure tool deflection is minimal.
So am I crazy for thinking this guy is crazy about using a boring bar when a rougher/finishing interpolating endmill will work just fine? Lead in and lead out will be used of course. Also, will he be able to tell a difference in surface finish from a boring bar? Never used a boring bar except for in school using an old Bridgeport. Thanks!