Originally Posted by
rlockwood
Splines must be exploded into arcs/lines. Most cad/cam software will have some sort of "Arc-Fit" function to handle this, with a maximum deviation tolerance. Others will explode to lines, which causes some level of faceting (think disco-ball). If your software only explodes to lines, you will have a trade off to make, and your NC controller will come into this equation. Too few facets and your part looks ugly. Too fine of facets and your controller can "data starve" (meaning it wont be able to process the lines fast enough to achieve the desired feedrate). With modern controllers (even pc based ones) there is a balance in between that is acceptable in both regards.
In either scenario, the issue wont be directly related to your taig, as these issues will be the same with any PC based controller-- regardless of what machine its connected to. Many machine controllers are marketed as "high speed", and this is in reference to the data starving condition.
Another thing to consider, however, is that most 3D tool paths are broken up largely into small straight line (g1) moves, as g-code only inherently supports arcs (g2/g3) on one of the three cartesian planes (XY, XZ, YZ, g17-19 respectively). Arcs can be spread evenly over a distance in the "other" direction of the plane, but are defined purely by a radius and start and end coordinates.