Non-Orthogonal MTD Axis

[Eskondedo]

I am trying to build an MTD for this Mazak QT350 MSY for milling only. I understand how to pull vectors for rotaries, but it doesnt seem like the linear axis' can work the same. Below I have the model rotated @30° around the center of the primary spindle center so the Y axis and Z move as expected but the turret carrier needs to traverse @45° and no matter what I place in the IJ vectors it will not accept it. Even if I was trying to get it to move with a single value, I="0.707" moves the same as I="1". Any help would be appreciated, if this is possible at all.

[Sean571]

Unfortunately, I do not think you can do this in PowerMill. PowerMill does not support simulation for turret lathes, and this slant bed machine is a good example of its limitations. While their might be slick workarounds, I do not know of any personally and I would avoid trying to simulate lathes in PowerMill entirely. 

But you are welcome to play around and try, and I'd be interested in knowing if you manage to put a hacky solution together. I suspect you'll be running into other issues along the way though.

[dsmits]

I know its not recommended but maybe possible if you change
<machine xmlns="x-schema:PowermillMachineTool" POST="pmpMultiaxis.*">
TO
<machine xmlns="x-schema:PowermillMachineTool" POST="SimPost.">

[Sean571]

So after I replied initially, I got curious and I played around a bit and found a hacky way to have your X axis move at a different vector.

If you wrap your X axis in a new machine part that is a rotary axis and set the home position to 45 degrees, this will have the X axis default to moving at a 45 degree angle around the Z (with the vector I picked). Then just set the priority to HIDDEN and now, the user has no way of changing the rotary angle of the fake axis.

    <machine_part>
      <axis>
        <control_info ADDRESS="R" HOME="45" PRIORITY="HIDDEN" />
        <simple_rotary X="0" Y="0" Z="0" I="0" J="0" K="1" />
      </axis>
      <machine_part>
        <axis>
          <control_info ADDRESS="X" MIN="-1016" MAX="0" />
          <simple_linear I="-1" J="0" K="0" />
        </axis>
      </machine_part>
    </machine_part>

 
It's hacky and Might cause some other issues that I can't foresee, but It seems to work! 

[Eskondedo]

This looked like a potential solution but I failed to mention the other moving parts. The Y axis sits on top of the sliding "X" and the two move simultaneously when machining I've rotated the entire model about the Z to make the Y and Z move orthogonally. There is no intention to use this machine for turning using PowerMill, only milling operations. While the 45° axis may not be a serious need for simulation, the motions related to the physical machine will not match. I've attached the MTD file to this response in the hopes it can be done, even with a cobbled solution.

[Sean571]

My original theory was correct, you just needed to work out some of the details to make it work for this configuration. I ended up getting it to work by changing a few things.

First, I Changed the world coordinate system so that the X and Z were perpendicular instead of the Y and Z. This way I could wrap the fake rotary axis around just the Y axis and not both the X & Y. Next I rotated the Y CAD around the world workplane 45 degrees so that it lined up with the world, Y axis.

Then in the mtd, I had the fake rotary axis home position set to -45 degrees so that it rotates into the correct position, and now moves at a 45 degree angle from the X.

Attached is the solution I came up with.

[Eskondedo]

While this moves as expected manually I don't think the ability to simulate with it will work. No matter what I do I get the same error:

I tried adding the appropriate strokes to each axis, I removed them, nothing seems to allow me to simulate. It would appear that the hidden rotary axis isn't allowing the rest of the axis' to move.