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+-- Thread: How to grind a cutter for lead screw/power feed? (/showthread.php?tid=7326484)
How to grind a cutter for lead screw/power feed? - jgourlay - 12-26-2016
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?
RE: How to grind a cutter for lead screw/power feed? - daddo - 12-27-2016
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.
![[Image: bitwood_zpssee1jwx1.jpg]](http://img.photobucket.com/albums/v89/daddo/bitwood_zpssee1jwx1.jpg)
RE: How to grind a cutter for lead screw/power feed? - jgourlay - 12-27-2016
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?
RE: How to grind a cutter for lead screw/power feed? - daddo - 12-27-2016
(12-27-2016, 09:33 AM)jgourlay Wrote: 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.
RE: How to grind a cutter for lead screw/power feed? - oreos40 - 01-06-2017
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.
RE: How to grind a cutter for lead screw/power feed? - jgourlay - 01-09-2017
Thanks!