[nfrees114]

Hello All- So I've done these parts for years. I usually do 2 runs of 50 or so per year. I've tried multiple different ways and on this recent run of 50 I tried the same operation I've used 3 or so times now and it's just not working at all anymore. Now it didn't work "great" before but it worked and got the job done. Attached are some pictures of the operation I'm doing, the tool I'm using, the set up I have. It's a DOM tube 2-3/8 OD. I'm turning an inside groove of half moon 1/4" Dia at the bottom of this part.

-When I first started doing these I used a 1/4" ball end mill and set it up in my Haas and did it that way while I was doing the other operations in the lathe. It was a pain, but again, "it worked"

-Then I decided to grind my own tool and just plunge in like an inside groove on the Lathe. I ground one out of HSS (same tool you see in the picture). It worked, and would work really well for the first .040" or so but any deeper than that and it would scream like heck. And I have to go .125" deep (half the dia) so it was just a squealing mess... But again, it did work. I just had to take my time and power through it. I would spin at 450 RPM and plunge by hand pretty slow. I tried different speeds but nothing seemed to help.

-Just yesterday I thought I would grind a smaller Dia tool and try and plunge a couple times and then profile. Again, squealing a lot....

I've thought about buying a smaller button tool (like the pic attached) and then grinding the holder in a arc so it could be used for interior grooving. I just didn't want to spend the money $150+ and then have it not work any better...

Thought I would get on here and get some thoughts on this. Please let me know your thoughts and if you have any questions.
Thanks!
-Nate
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[nfrees114]

[InMesh]

I have always taken a couple of bites at this type of thing and lowered my center of the tool ,so I do a center cut and then the sides then I have done them by eye and by hand .

[timlkallam]

Dom tube doesn't machine well at all could you use a different material.