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I'v been looking at annular cutters (think hole saws on steroids) as an alternative to large drill bits, ~9/16 and up, in both the mill and the lathe. It seems a pretty good way to get to a large diameter, before going to the boring bar or reamer.
Has anyone tried it? Any comments?
Mike
SB 10K (1976) Rockwell vertical mill (1967) Rockwell 17" drill press (1946) Me (1949)
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The annular cutters are best for short depth holes and ONLY for through holes as they make a slug, just as a hole saw would Very limiting. I've never felt constrained by using twist drills and stepping up on size as I get much over 1/2" diameter.
They are a good tool for repetitive work, as the cost is high per unit. I would use extreme caution on a lathe because the slug could get whipped out of a chuck at high speed. Even big spade drills that can push a thin disk as they break through can be dangerous.
Holding onto them is tricky too, as the most common brands have proprietary adaptation, requiring a special holder for your spindle.
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Thanks. It was just a thought!
Mike
SB 10K (1976) Rockwell vertical mill (1967) Rockwell 17" drill press (1946) Me (1949)
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I've used them in a home made holder. Work very well and in thin(ish) plate the holes come out round.
The one in the photo is 25mm dia (I think) the speed would be 90 to 150 rpm.
I also have a larger ones up to 50mm.
DaveH
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Being carbide tipped, you could easily (and safely) run those a LOT faster than those speeds.