Custom Made Carbide Turn Insert Questions

[mgb1974]

I have a turn job that I am doing. The part is roughly 30" in diameter and needs a groove on the ID of the part. My questions is I need to make a carbide piece to cut this since I can not find any insert that matches up. It is .100 deep, .060 wide and at a 23.25 degree angle.

My questions is can I take a solid piece of carbide and wire EDM cut the shape i need? What about the tool edge?

My plan was to build the angle into a special older I will grind. It will be done on a CNC Lathe.

Any insight would be appreciated thanks!

[Delw]

I am sure you have a t-bar extension holder with a big machine like that 30"

if you do get a micro100 cut off tool , cut a full radius on it. then put it in the t holder with as little as possible sticking out we used them many times on all different types or material

[mgb1974]

This is a newbie questions but what exactly is a T-Bar extension Holder??

[Delw]

Its a bar that comes out of your tool holder and allows you to put a tool 90º looks like this T hence the term T bar extensions

we used to use them alot when we did big rings, we used 1" standar square holders like VNMG to do profililing that we couldnt reach with regular tooling.

[PixMan]

This is very easy to solve! Use a standard insert, 1.53mm wide, and make a holder. Custom inserts are expensive, and so if you can simply adapt a holder you'll have an affordable and endless supply of inserts in a variety of grades. You have the right idea, you just need to start with the right insert.

I strongly suggest looking at the VTG-style (double-ended) inserts from Valenite. The VTG 1.6 N 15 PG insert is .063" wide, can easily go far deeper than .100", and has great chip control in all three grades (5810, 5820 and 5735). If you need and angle on the tip of the insert, there's two different versions, a left and a right 10 degree angle. A slight grind to the tip and you'd have what you need without removing all the chipbreaker form. Those are VTG 1.6 L10 15 and VTG 1.6 R10 15, but only available in 5820 grade (still good for almost every material.) If the .063" width is too much, you can grind .0015" from each side without disturbing the chipbreaker form.

For a holder, pick up the VGSCA L (or R) 20 holder, and make your own shank to fit the "EconoGroove" style key of those holders, with your angle on it.
Go to Valenite's website and you can download the "Turning 2007" catalog to see what tooling I am referring to. Fair warning, big file. The VGSCA holders are on page D18, the inserts are on page D37. You can see the straight EconoGroove shanks on page D19-D20.

Hope this helps.