New Carbide Tool Holder and Carbide Inserts

for the new lathe i ordered a new tool holder and carbide inserts. my other lathe wasn't too
good with the tool pressure needed for carbide. so this is my first tool holder that holds CNMG
inserts, kind of exciting!


These inserts have excellent chip management and produce small chips as a result of the small
structures on the insert that reform the chip after cutting and cause to fracture in small or at worst
short curly chips instead of the long strings that wrap around the work, get recut, and trash the

The holder has a 1/2" shank which requires about 1/8" of spacing to center it on the workpiece. i
could use 5/8" shanks but i am taking baby steps on the new lathe. the shank is from
and cost $32 and the two extra CNMG322 inserts were $8.50 total. i usually order from mcmaster
carr, shars, or victornet. i chose shars because of the lowest shipping charges.

the inserts have no rake, that is the angle of the cutting edge relative to vertical. the holder has a
negative 5 degree rake on the front and right hand side. the holder provides the rake, not the
insert as in case of most hand ground hss toolbits. you can see the rake on the end and side
view here:



what i really like about this tool is that it can face cut as well as a regular right hand cut, the insert is slightly
diamond shaped and the holder has sufficient relief to give perfect facing cuts. very cool. the lathe has x and z
power feeds whichs makes it almost a pleasure to do serious 60 thousandths cut on both axis.

the holder came with an insert even though it said no insert included. the included insert has little chip
management other than the indent behind the cutting edge. this insert provided a long chip that needed
a little needle nose pliers help to extract the chip. this picture shows the included gold colored insert along
with one of the CNMG322 inserts. you can easily see the difference.


how's that for excitement???

these two tools have 5/8" (lower) and 3/4" (upper) shanks. the 5/8" needs a 62 thou shim and i ended up making an adapter for the 3/4". problem with the adapter was the added leverage from the tip to the quickchange post. i couldnt get myself to defile a $100 kennemetal holder even though it was a gift, but seeing you did it.....
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