Radius Cutter

[wareagle]

Well, I have a working radius cutter. Not a finished unit yet, but servicable. I am going to incorporate a few more features on the unit, and I am going to take some material off of the insert holder to enable making a tighter ball. But, for now, if need be, I can cut a radius.

 

[cfellows]

That's a nice looking unit. How big a ball will it cut?

Chuck

 

[wareagle]

Thanks for the kind words. It is at best a hack job, but it works. I used tapered bearings (trailer axle bearings) so I could elminate the play on the turret. It worked out very well, actually. For some finishing touches, I am going to put a scale on the slide to know what diameter (roughly) is being cut, and am also looking at mounting a tool bit on the opposite side of the insert to enable a range of shapes, rake angles, and the like for different applications.

For capacity, it should be able to cut about a 4" diameter ball. It will definately open up that far, but as far as how rigid the set-up will be once out there remains to be seen. I don't foresee ever needing to turn a ball anywhere near that large, but who knows! I never would have thought that I would have had to drill #80 holes, either!

W/E

 

[Powder keg]

When I was going to school, We had to make a 6" ball for a ball valve. It was for the city to get their water plant running. A replacement was 2 months out because it was special valve. That was a fun job:O)

Wes

 

[J. Tranter]

What type of bit are you useing? And do you have a video of how it works?
John

 

[wareagle]

What type of bit are you useing? And do you have a video of how it works?
John

It is a TNMG (95% sure, but will have to verify) insert. I had some on hand, so that's what I based the holder on. Sorry, no video at this point. Haven't really had the time to shoot and edit videos. I will start taking some vidoe after the holidays of some various things, this being one of them.

 

[cfellows]

It is a TNMG (95% sure, but will have to verify) insert. I had some on hand, so that's what I based the holder on. Sorry, no video at this point. Haven't really had the time to shoot and edit videos. I will start taking some vidoe after the holidays of some various things, this being one of them.

That's probably a TPG which is what I use all the time for my cutting tools. The picture shows a TPG221, the 221 designating size. I use TPG321 which is 3/8" instead of the quarter inch shown. The radius of the the point is designated by the last digit, 1 being 1/64", 2 being 1/32", etc.

 

[wareagle]

Well, I must make a correction on the insert. What I am using is a TNG322 insert, not a TNMG. The reason for this insert is I had 10 shipped to me by mistake, and was told just to keep them when I called to let them know they made a mistake on the order. Rather than let them collect dust, I figured this would be a great candidate to utilize them.

Chuck, you are right in that the TPG inserts are very common, and I use quite a few of them myself. What really amazes me is the price that some of these inserts go for. I am probably not going to like replacing the inserts on my boring bars when the time comes! :-\