Thanks, it seems you're correct. I've been programming toolpaths on the top plane with this machine using another post for so long I didn't even notice that it was always orienting the C-axis to 90 degrees when I did so. Putting the toolpath on the back plane is equivalent to 0 degrees of rotation. This is successfully processed without the error, but I still need the others to work. Which leads to the next question: What are the steps to cause it to use the C axis for the TOP, FRONT and BOTTOM planes - and everything in between? I found the chapter on Rotary Processing (MP-Ref-Guide_Legacy-chapters.pdf) wasn't very clear. It presented some code from one of the template posts (MPFAN, maybe?) but didn't go into enough detail on what each of the lines was doing and why. I understand the matrix transform of coordinate systems, but what exactly needs done in the post to make it happen, and what's the reason behind each step?

For a Y-axis lathe having both axial and radial live tools, how do you differentiate between them in the post? Axial tools are programmed from the RIGHT plane and seem to be okay, but radial tools are programmed from the TOP plane (and others using the C-axis for rotation) and aren't output with the correct axis motion. How are these translated correctly to avoid getting the following error message:? RUN TIME -OPID(4)- Only single-axis rotation is allowed! Angles may be incorrect. Assume a blank slate with none of the variables or postblocks from the existing default posts.

When I was browsing through some resources, I came across an example post in one of the CHook projects. I was surprised to see that it seemed to be passing parameters to post blocks when I haven't seen any documentation on this. Does anyone know how exactly this is intended to work with respect to declaring variables, naming, etc? Any chance a value can also be returned from a postblock? Here's the contents of the file "MPDraw_Ex.mcpost": [POST_VERSION] #DO NOT MOVE OR ALTER THIS LINE# V20.00 P4 E1 W20.00 T1517249798 M20.00 I0 O0 #region User Settings #<UserSettings> MPDrawDebugOutput : no$ # Output arguments passed to the MPDraw.dll geometryLevel : 101 # Level to create/remove geometry #</UserSettings> #endregion End User Settings #region Post Settings rotary_type$ : 5 #endregion End Post Settings #region Format Statments fs2 1 0.8 0.7 fs2 2 1 0 1 0 #endregion End Format Statments #region Draw Geometry #region Geometry Variable Initializations #region Enumerators # Geometry type DELETE@ : 0 LINE@ : 1 ARC@ : 2 # View number TOP@ : 1 FRONT@ : 2 BACK@ : 3 BOTTOM@ : 4 RIGHT@ : 5 LEFT@ : 6 ISOMETRIC@ : 7 #endregion End Enumerators #region Numeric Variable Initializations # Return value for dll function dllReturn : 0 # Line start and end point variables lineStartX : 0 lineStartY : 0 lineStartZ : 0 lineEndX : 0 lineEndY : 0 lineEndZ : 0 # Arc variables arcView : 0 arcCenterX : 0 arcCenterY : 0 arcCenterZ : 0 arcRadius : 0 arcStartAngle : 0 arcEndAngle : 0 # Line start and end point variables formatted for output to MPDraw.dll fmt "" 1 sx fmt "" 1 sy fmt "" 1 sz fmt "" 1 ex fmt "" 1 ey fmt "" 1 ez # Arc variables formatted for output to MPDraw.dll fmt "" 2 arcview fmt "" 1 acx fmt "" 1 acy fmt "" 1 acz fmt "" 1 ar fmt "" 1 as fmt "" 1 ae # level and geometry type variables formatted for output to MPDraw.dll fmt "" 2 level fmt "" 2 geometryType #endregion End Numeric Variable Initializations #region String Variable Initializations ssq : "'" # Single quote character sdq : '"' # Double quote character sspace : " " # Space character sMPDrawDLL = "MPDraw.dll" # Constant string containg 'MPDraw.dll' sdeleteData = "0" # Constant string to hold the delete data slineData : "" # String to hold the line data sarcData : "" # String to hold the arc data sMPDeleteArgs : "" # String to pass the delete arguments to MPDraw.dll sMPLineArgs : "" # String to pass the line arguments to MPDraw.dll sMPArcArgs : "" # String to pass the arc arguments to MPDraw.dll #endregion End String Variable Initializations #endregion End Geometry Variable Initializations #region Geometry Post Blocks # Remove all geometry from a specified level pDeleteGeometry(level) # Set the geometryType geometryType = DELETE@ # Construct the delete argument string(sdeleteData, level, geometryType) sMPDeleteArgs = ssq + sdq + sdeleteData + sdq + sspace + sdq + drs_str(2, level) + sdq + sspace + sdq + drs_str(2, geometryType) + sdq + ssq # Call the MPDraw.dll passing it the constructed argument string dllReturn = dll(sMPDrawDLL, sMPDeleteArgs) # If MPDrawDebugOutput = yes$, write the delete arguments to the NC file if MPDrawDebugOutput, " Delete Arguments : ", *sMPDeleteArgs, e$ # Draw a line on a specified level pDrawLine(sx, sy, sz, ex, ey, ez, level) # Set the geometryType geometryType = LINE@ # Convert the line data to a string slineData = drs_str(2, sx) + sspace + drs_str(2, sy) + sspace + drs_str(2, sz) + sspace + drs_str(2, ex) + sspace + drs_str(2, ey) + sspace + drs_str(2, ez) # Construct the line argument string(slineData, level, geometryType) sMPLineArgs = ssq + sdq + slineData + sdq + sspace + sdq + drs_str(2, level) + sdq + sspace + sdq + drs_str(2, geometryType) + sdq + ssq # Call the MPDraw.dll passing it the constructed argument string dllReturn = dll(sMPDrawDLL, sMPLineArgs) # If MPDrawDebugOutput = yes$, write the line arguments to the NC file if MPDrawDebugOutput, " Line Arguments : ", *sMPLineArgs, e$ # Draw an arc on a specified level pDrawArc(arcview, acx, acy, acz, ar, as, ae, level) # Set the geometryType geometryType = ARC@ # Convert the arc data to a string sarcData = drs_str(2, arcview) + sspace + drs_str(2, acx) + sspace + drs_str(2, acy) + sspace + drs_str(2, acz) + sspace + drs_str(2, ar) + sspace + drs_str(2, as) + sspace + drs_str(2, ae) # Construct the arc argument string(sarcData, level, geometryType) sMPArcArgs = ssq + sdq + sarcData + sdq + sspace + sdq + drs_str(2, level) + sdq + sspace + sdq + drs_str(2, geometryType) + sdq + ssq # Call the MPDraw.dll passing it the constructed argument string dllReturn = dll(sMPDrawDLL, sMPArcArgs) # If MPDrawDebugOutput = yes$, write the arc arguments to the NC file if MPDrawDebugOutput, " Arc Arguments : ", *sMPArcArgs, e$ #endregion End Geometry Post Blocks #endregion End Draw Geometry #region System Post Blocks pheader$ # pheader$ - in this example this post block runs first # Remove all geometry on a specified level pDeleteGeometry(geometryLevel) psof$ # psof$ - in this example this post block runs second lineStartX = vequ(x$) lineEndX = vequ(m7$) # Create a line on a specified level starting from the current x$,y$,z$ and extenting to the tool the toolplane Z pDrawLine(lineStartX, lineStartY, lineStartZ, lineEndX, lineEndY, lineEndZ, geometryLevel) peof$ # peof$ - in this example this post block runs last arcView = TOP@ arcCenterX = 0 arcCenterY = 0 arcCenterZ = 1 arcRadius = .5 arcStartAngle = 0 arcEndAngle = 360 # Create an arc on a specified level using the values above pDrawArc(arcView, arcCenterX, arcCenterY, arcCenterZ, arcRadius, arcStartAngle, arcEndAngle, geometryLevel) #endregion End System Post Blocks

I realize I'm 7 years late to the party, but since Google searches still direct people like me here I'll share the very simple and elegant solution I used: s_some_string = regex("\S.*\S", s_some_string, 0) # Strip leading/trailing whitespace