Angled HSS toolholder and tool sharpening angles

Frank

20 degrees being pretty much the maximum top rake you will ever need you just flatten off as required to get the right one for the job.  It may help to think of the bottom surface of the tool-holder as your zero rake reference.

One oft overlooked advantage of tool-bit holders is that they make a good "poor boys" Quick Change system substitute as reference to a tool height gauge when changing bits also sets the projection to pretty close limits.  If you fancy trying this best way is to use a slim single slot block type mount, fabricated construction is OK if you don't fancy heavy milling, and arrange some way of gauging the tool tip height off the top of the mount.  The job in progress tends to get in the way of the usual sort of gauge. Use the bent to the right holder, if you have one, for all normal work as it lets you get closer in to the chuck than the straight one without worrying about clonking the saddle.  Bent to the left for facing work.  Set the business end at 90 degrees to the bed for normal turning and parallel to it for facing.

All the angles go on the tool so they can easily be replicated using simple templates or a SouthBend style holder if you feel fancy. I feel that a major reason for finish problems encountered by inexperienced workers is the inability to exactly reproduce the tool shape.  Slight shape changes when grinding usually mean that the tool needs to be handled a bit differently for best results.

Clive