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Eric R Snow
 
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Default Parting tool drift

On Thu, 29 Jul 2004 00:19:16 -0500, Don Foreman
wrote:
Glad I could help Don. About those Cleveland bits. Worth more than
twice what you paid. They really work so much better than the imported
ones. Especially ones from India. I bought, by mistake, some of the
Indian ones. Ended up throwing them out. Good for absolutely nothing.
And will make you think you have a problem with your setup or
technique. In the future, you will probably find it works best to just
grind the face of the parting tool. Grind back far enough to restore
the original tool profile. Then, if you need to part off a large
diameter, you won't need to grind more on the top or sides.
Eric

Thanks, Eric and Anthony! I ground the top of the bit a little and
ground a bit of relief on the top of the T as well. It runs much
better now. I think I got bit by bad import quality on this one.
The Mo-Max Cleveland bits cost twice as much, but they sure work well!



On Tue, 27 Jul 2004 14:11:07 -0500, Don Foreman
wrote:

I have a T-shaped parting tool in an Aloris BXA7 holder that won't cut
straight. It drifts to one side or the other as the cut progresses.
The bit is .063" at the bottom, .094 at the top, .686 high. As far
as I can tell the cutting edge is ground square (parallel to the
lathe axis), the bit is vertical in the holder to within a thou or
two, and the bit was square with the workpiece at center height.

I have a thinner tapered parting bit that does cut straight. It's
.0625 at the top, .043 at the bottom, .687 high.

The lathe is a 15x50 gearhead, no problem with stiffness or rigidity.

I'm not exactly a newbie with a lathe, but this one has me puzzled.

Any suggestions about what's going on here, please?

Thanks!

Don Foreman