Need help on machining process for tubing bender dies

The blank is put into a rotating table/fixture under a 1-1/2" round nose end mill. Depending on the tubing you are bending, aluminum maybe alright. Also depending on the tube material and wall thickness, you might find that a 5" radius is too tight and the tubing will crinkle. Let us know how it turns out. Lane

I would mount the material on a faceplate and use a radius attachment to cut the groove. Well, I'd hog it out first using a parting tool. If you don't have a radius attachment then you can use Lautard's method to approximate the groove using very fine steps, and then use a file.

Grant

DVN wrote:

This can be done with a long standard milling cutter and the stock mounted on a vertical rotary table. The cut is made with the side of the cutter as the stock is turned.

I have done lots of them. One 20" in diameter for a 6" pipe. The best way is to use a lathe with a radius turner. I built one about 15 years ago that's simalar to the Holdridge radii cutter in the MSC catalog. This is the best way to do it. I have seen people do it with the side of an endmill and a rotary table. I have also seen it done with a boring bar and a rotary table on the mill. I prefer to do it on the lathe. I usually use either acrolloy or ETD 150. About 32 RC. I have made them for a pipe bending shop. I haven't made any for several years, so I don't remember exactly how many bends they could get from a die. But it was in the 100,000's of bends.

Richard W.