I do thousands of these types of o-ring grooves and for many years. I always rough the groove first with a straight end mill, then finish the form with the dovetail. It repeats much better, nicer finishes (since many of these types of application require a really good finish for sealing) and doesn't eat up the tool (dovetail) as fast.
You can actually run the dovetail faster if you roughed it first.
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It's just a part..... cutter still goes round and round.... |