(info: Imperial Threading)
;
;

o<threading-imperial> sub
  
   (Change these values)
   #<_MajorDiameter>            = #1 (Major Diameter inch)
   #<_TPI>                      = #2 (TPI)
   #<_Z_Finish>                 = #3 (+/- Z Length inch, Z)
   (Don't usually have to change these values)
   (PeakOffset is initial tool clearance)
   #<_Allowance>                = #4 (=0.0015 Diameter external only)
   #<_PeakOffset>               = #5 (=-.004 Peak Offset -external, +internal, I)
   #<_TipRadius>                = #6 (=0.004 Tip Radius)
   #<_Z_LeadIn>                 = #7 (=0.1 Z Leadin)
   #<_Z_Final>                  = #8 (=2 Z Final Position)
   #<_Spring_Passes>            = #9 (=1 Spring Passes, H)
   #<_First_Cut_Depth>          = #10 (=0.007 First Cut Depth, J)
   #<_Depth_Regression>         = #11 (=1.2 Depth Regression, R)
   #<_CompoundSlideAngle>       = #12 (=29.5 Angle, Q)
   #<_TaperAmount>              = #13 (=0 Taper)
   #<_TaperType>                = #14 (=0 Taper Type, L)

   #<RPM>                       = #15 (=500 Spindle RPM)
   #<ToolNumber>                = #16 (=1 Tool Number)
   #<Coolant>                   = #17 (=8 Coolant 8 On 9 Off)

   (check to see if tool set)
   o100 if [#5400 EQ 0]
      (msg, Tool not set)
      M2
   o100 endif

   o220 if [#<_metric> EQ 1]
      #<CurrentMetric> = 1
      G20 (set imperial units)
   o220 else
      #<CurrentMetric> = 0
   o220 endif

   (Calculations)
   #<_Pitch>=[1 / #<_TPI>]

   (calculate ThreadDepth, K)
   o110 if [#<_PeakOffset> GT 0]
      (internal = pitch * cos30 * 2 * 6/8 - 2 * tip radius)
	  #<_ThreadDepth>=[#<_Pitch> * 1.299 - 2 * #<_TipRadius>]
	  (thread height = pitch * cos30 * 2 * 5/8)
	  #<_MinorDiameter>=[#<_MajorDiameter> - #<_Pitch> * 1.0825]
	  #<_Diameter>=[#<_MinorDiameter> - #<_PeakOffset>]
   o110 else
      (external = pitch * cos30 * 2 * 7/8 - 2 * tip radius)
	  #<_ThreadDepth>=[#<_Pitch> * 1.5155 - 2 * #<_TipRadius> + #<_Allowance>]
	  #<_Diameter>=[#<_MajorDiameter> + #<_PeakOffset>]
   o110 endif

   G7 G18 G20 G54 G90 G94
   G95 (feed per revolution mode)
   T#<ToolNumber> M6 G43
   M3 M#<Coolant>
   F0 S#<RPM>

   (Go to start diameter and Z Lead in)
   G0 X#<_Diameter> Z#<_Z_LeadIn>
   (Thread)
   G76 P#<_Pitch> Z#<_Z_Finish> I#<_PeakOffset> J#<_First_Cut_Depth> R#<_Depth_Regression> K#<_ThreadDepth> Q#<_CompoundSlideAngle> H#<_Spring_Passes> L#<_TaperType>

   G00 X#<_Diameter>
   G00 Z#<_Z_Final>

   M5 M9

   ; Restore to normal units
   o230 if [#<CurrentMetric> EQ 1]
     G21 (metric units)
   o230 else
     G20 (imperial units)
   o230 endif
o<threading-imperial> endsub