5-Axis-EMC

Hi Jon

>Ah, of course, this now reminds me why this is necessary!


>Yes, of course, you just want it simple! But, there's the rub, there is
>no clear way, in the RS-274D specification, to just throw in some
>extra (rotary) axes, and have them perform in a consistant manner!

>So, to avoid messy kludges that could make a real disaster of a simple
>task, it really is necessary to properly manage the movements based
>on the real physical arrangement of the machine. It looks like at last
>this will be properly built into EMC, and the setup should become
>pretty formulaic, perhaps just a set of parameters in a file loaded at
>run time. I do want to put a single rotary axis on my mill for cutting
>gears, busts of people's heads, and maybe even turbine blades.
>It might be real nice to have all this set up so that I can normally have
>an A axis, but move the (NC) dividing head to become a B axis when
>desired, and also put a fixed tilt on it, as if the A axis was stacked on
>a B axis set to some fixed value for best turbine blade access.
>With a nice little table that could be read in, this would be a very easy
>thing to do.

Everythink was clear to me until we bought a Micron-5-Axis Center.

On all mashines-controllers I am familiar with (Siemens
8M,880,850,840D,840C,Bosch CC300/330,Dialog4,Dialog11) the movement of
circular-axis is in degrees. G01 B360 F360 means : make one full turn in one
minute.
The basic for computing the fedrat is a circle with 114.598mm Diameter ==>
360 degrees =360mm
In case: G01 X100 B150 F150 . B becomes the leading axis, because of the
longest way . the move will take 1 minute.
In case : G01 X100 Y50 Z50 B100 F150 . The cartesian way will be 122.5mm ,
the rotary 100mm, so the cartesian way is the leading way, the move will take
0.816 min.

At the micron the basic -circle has a diameter of 1" =25.4mm. ( but it can be
changed in the mashine-setup) and "G01 B360" lets the rotary axis turn 4
times.
Is that our Problem ?
I think it is impossible for the mashine-controller to compute the fedrat of
the cutter-tip on the turbine-blade . Too many variables. (We also sometimes
arrange the the rotary axis different , depending on the parts we produce (By
the way, round about 30000 turbine blades a year, 2500 for fighter
aircrafts).
But it is not nessesary. In the programming systems (Catia, APT360, APT140,
NREC) we define the Origin, the mashine-setup. For example: we define the
fedrat F30 for moveing the cutter tip through the material. The postprozessor
makes a X Y Z B C F357 from it.
But that all is the secondary problem for me . I will be glad when my mashine
starts working 5-Axis simultaniosly ( if the fedrat is o.k. or not.)
Thanks for the help.
Peter