On Tuesday, January 22, 2019 at 7:30:09 PM UTC-5, Martin Eastburn wrote:
A torus is 4 dimension so you need more axis than 3.

It's not "4 dimension," but you need an additional half-axis (a rotary indexed"flip" to machine the back side of the donut) to machine it with a conventional machine tool. It could be machined, theoretically, with a 3-axis CNC EDM and a disk-shaped electrode, depending on the relative diameter of the hole in the torus. Actually, with a weirdly shaped electrode, you could do it regardless of hole size.

Many shapes - saddles are multiple dimensions.

No.

Saddles are not just for
horses but holds pipe and rods.

Saddles (hyperbolic paraboloids) are widely used for roofs in architecture. The shape can be milled with a conventional 3-axis mill with continuous-contouring capability and somebody who can program in something more than ordinary shop math.

A really interesting thing about saddles is that they can be *lapped* by hand. In fact, they sometimes are, when someone tries to do the three-flat lapping trick to make flat surfaces, and they screw up the rotation sequence. Surprise! You made a hyperbolic paraboloid without even trying! g


All sorts of shapes require more than
an old fashioned 3.

Try to mill a Propeller with a 3 axis - have the 3 blades cut in their
complex shape.

Again 3 axis and a 180-degree rotary flip of the fixture. That may not be an efficient way to do it, but it can be done.


Martin

On 1/13/2019 7:25 AM, JimmyMcGill wrote:
Hey does anyone know what the correct name for this 4 axis set up is
called and possibly who makes it?

http://www.eevblog.com/forum/reviews/what-is-the-name-of-this-5-axis-positioning-tool/?action=dlattach;attach=617821;image


--
Ed Huntress