PowerMill Forum
Welcome to Autodesk’s PowerMill Forums. Share your knowledge, ask questions, and explore popular PowerMill topics.
Showing results for 
Show  only  | Search instead for 
Did you mean: 

Force trunnion rotation direction solution

Message 1 of 3
1068 Views, 2 Replies

Force trunnion rotation direction solution

Hello, I am in the process of writing a 5-axis post processor for a HAAS VF4 with a TR160 trunnion based off of the example one prepackaged with Powermill. The cradle A axis is along the X axis with positive rotation moving the part toward the operator (top -> front). The C axis is along the Z axis with clockwise positive rotation (right -> front). I have programmed simple toolpaths for a 3+2 axis block for both FUSION 360 and Powermill. The FUSION 360 HAAS NGC post (with A axis reversed option checked) mills the front face of the cube with the cube closer to the operator(A90 C-180), which is preferred. The Powermill post mills the front face away from the operator (A-90 C0), which is more difficult to monitor. Not to mention it also mills in the Y direction instead of X! How should I fix it so that Powermill mills it in the same way that FUSION 360 does? Also, Powermill rotates the cube for the initial op C90, then mills along the Y axis instead of just machining along X with no rotation.  I would like to force X axis travel for that (Orientation vectors?). Please let me know how I should fix this problem. The NC code and machine kinematics are attached below.

Labels (4)
Message 2 of 3
in reply to: nh.sanders00

This page will allow you some control over it.


Without diving too deeply into what you've got going on in your post/etc the Machine Axis Control will let you lock the rotation in a specific way rather than willy-nilly as the post sees fit.  This may be simpler than editing the post.


In this case a fixed direction will be relative to whatever work plane you are on, what ever it simulates is what the machine will do.

Message 3 of 3
in reply to: mribble

Thank you for the recommendation, @mribble. However, in this case the post processor axis were messed up badly. I had assumed the XY axis would be aligned with I and J vectors, but they are anti parallel. On top of that, 1st Rotary (A) is actually the C axis [0, 0, -1] and the 2nd Rotary (B) is the A axis [1, 0, 0]. I will attach a screenshot of the kinematics setup that appears to generate good code. I have not physically verified it, only read the G-Code. Correcting the axis was a confusing pain, but I worked it out scientifically based on the HAAS example one. I hope these settings will help anyone else setting up a similar HAAS 3 axis with a trunnion. If anyone notices any mistake, please reply to this. Please note that these settings are a sort of "rotational mirror" that bring the part near the user instead of away as the simulation would suggest. It should accomplish the exact same part if my calculations are correct.

Can't find what you're looking for? Ask the community or share your knowledge.

Post to forums  

Technology Administrators

Autodesk Design & Make Report