Hi, Frank,
I have never taken much time to get accustomed to spiral blades, had some issues with them slipping in the blade clamps when I first tried them and
constantly breaking blades and I don't want to keep ordering smaller drill bits when I have gotten along just fine without them. (that probably sounds
grouchy or something in print but, it is not meant to sound that way. Sometimes printed words without body language or facial expressions can be
misconstrued).
I usually don't have to alter the patterns but, this one had some really fine veining lines so close together that I do not really know if they could have been
cut with a spiral blade without chipping the baltic birch.
God Bless! Spirithorse