POCKET NC'S HOME POSITION WITH RESPECT TO SETTING UP FUSION 360 CAM

For those struggling to get Fusion 360 working with Pocket NC I thought I'd put this basic info on here to help.

Fusion 360's setup WCS Coordinate system must match Pocket NC's default homing origin.
1) In the first photo you see the Pocket NC at it's home position. And you can see the default XYZ table directions.  I also put the PNC vise oriented along the X Axis on the right side of the rotary center-line. (Notice the Z Axis Blue Arrow shows the positive direction that the Z Axis moves on the machine. It's important to see this with respect to the B Table.

2) The second photo shows the Fusion 360 CAM SETUP Screen. Notice the Z Axis matches the actual Pocket NC's Z Axis when it is homed.

3) The Third photo shows an engraving tool path. But notice it's Z Axis is now pointing upward. It's now perpendicular to the B Rotary Table. (See the Blue Z Axis Arrow.)  It is the direction the tool needs to approach the part and cut it. 

Also notice within the dialog box for the Engraving Tool Path, The origin is specified as WCS. That is making a hard reference to the Z Axis that is used in the earlier Fusion 360 CAM SETUP. Now the post can tell that starting out Z needs to be output with respect to the WCS> The Pocket NC Post is setup so that starting out the rotary's are at A0 B0 just as they are when the machine is homed. Next when the tool path is processed the post sees that the engraving Tool Z Axis orientation and is now in a different orientation. And it outputs A90 B0 so the tool path will move the PNC Rotary Tables correctly to get the tool facing the part. All the clearance planes etc need to be hard set with respect to the math of the Pocket NC.

One other thing to note. Currently Pocket NC support 3 Axis Fixture Offsets, but by default doesn't really use them. Mainly to be consistent as it does not support 5 Axis Fixture Offsets. This is why we need the .885 Value that describes the A and B Rotary Center Line Intersection. And that is what we can use to drive Pocket NC is a relative position that is to this intersection as a WCS origin.

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