Just thought I share this....
Today I found a bug with Creo 2.0 M050 in regards to turning, this has caused us to scrap 5 wheels today of a new wheel type
NORMAL METHOD
Normal practice for roughing our tread profile is to stop the cut at the apex of the flange and then continue out on a tangent, we achieve this by setting a TREAD_APEX datum plane. Normally the tread is a single radius or two radius with a small flat in between, As such the common practice for creating the profile is to let it continue underneath, and let the datum end the cut, as shown below. This tread profile has two radius, but no flat in between. The datum is set to allow the cut to feed out at a tangent, as is the common practice.
INCORRECT TOOL PATH CALCULATION
of the R12 as its end point, not the datum plane as set as the end point for the cut, and the tool motion is in correct
CORRECT TOOL PATH CALCUTION
With the profile stopped at the end of the R16 radius and the cut set to stop at the APEX via the datum plane, the tool path calculates correctly as shown, it appears to calculate the R16 radius as one, taking the end point, of the TREAD_APEX-DATUM as its end point, and the tool motion is correct LEAVING A 1MM CUT as it should
The radius calculations should be at the end point of the cut, not the profile, it should calculate from the Datum plane selected to end the cut, but it isn't, it is calulating from the end of the profile, with the R12 added, it calculates the wrong arc movement. and we scrapped product.