How to grind a cutter for lead screw/power feed?

[jgourlay]

All:

My lathe has a saddle/lead screw.  I've never used it for woodturning, but in metal it's the bomb for making cylinders and tapers.  If I wanted to grind a cutter out of the standard 1/2" x 1/2" tool stock to take roundish stock round and to taper, what would that cutter geometry look like?

[daddo]

Your not clear- are you going to be turning metal or wood?

Are you making a bit from usual HSS?

I've ground one like this for wood- works good. My favorite for metal cutting is 8 degrees- for wood you could use 10-15 degrees or more since you don't need the strength at the edge.

 You may have to experiment with grinding angles and a right or left bit if you work into shoulders or near the chuck.

 I don't grind 1/2" much- takes too long- prefer 3/8".

 Not to scale of course.

[jgourlay]

Dado, thanks.  Yes, it's wood I'm interested in.  Do you high-polish all the edges like one does for chisel and plane blades?

[daddo]

Dado, thanks.  Yes, it's wood I'm interested in.  Do you high-polish all the edges like one does for chisel and plane blades?

  I do the usual ritual of honing - it's habit. The sharper and keener the edge, the longer it lasts because it runs cooler and does less work.

[oreos40]

I turn on converted metal lathes. its tricky but if you can relieve the top in the middle kind of like hollowing out the bow of a canoe you will get the best cut. if not then cut just one direction. both cutting edge relief AND chip relief angle will work the best.

[jgourlay]

Thanks!