Thread Angle

[Rocketmachinist]

I cannot figure out where the number for the thread angle are coming from. I am running a Generic Haas SL 4x post

G76 X.4963 Z-1. K.0331 D.0091 A29 E.05556

I cannot find where the A29 number is coming from. I found it being called from thdang but it doesn't seem to reoconize the values for the Thread Angle and Included angle. I don't understand where this number is coming from. Isn't is also suppose to be a 59 degree angle instead of a 29 degree?

[crazy^millman]

That number is correct since it is come down the 30 deg face of the thread. The angle is the angle in which the tool is stepping down one wall not the included angle.

[Rocketmachinist]

But it doesn't change when I choose an acme thread

[Rocketmachinist]

Also

https://diy.haascnc.com/g76-threading-cycle-multiple-pass-group-00-0

 

 

The tool nose angle for the thread is specified in A. The value can range from 0 to 120 degrees. If A is not used, 0 degrees is assumed. To reduce chatter while threading use A59 when cutting a 60 degree included thread.

[crazy^millman]

On and Acme thread if memory serves me correct it is 14.5 degree angle. Look on the 2nd page and change the thread angle there and you should get the output you are looking for.

%
O0000
(PROGRAM NAME - TOOLPATH GROUP-1)
(DATE=DD-MM-YY - 04-11-16 TIME=HH:MM - 12:49)
(MCX FILE - T)
(NC FILE - C:\USERS\RON\DOCUMENTS\MY MCAM2017\LATHE\NC\TOOLPATH GROUP-1.NC)
(MATERIAL - STEEL INCH - 1030 - 200 BHN)
G20
(TOOL - 97 OFFSET - 97)
(OD THREAD RIGHT  INSERT - NONE)
G0 T9797
G18
G97 S200 M03
G0 G54 X2.1646 Z.3112
G76 P010059 Q0 R0 <----- 59 Degrees
G76 X1.7396 Z-1. P1125 Q478 R0. F.07143
G28 U0. V0. W0. M05
T9700
M30
%

[crazy^millman]

Here it is out of the generic HAAS post setup to old style thread output.

%
O0000
(TOOLPATH GROUP-1)
(DATE=DD-MM-YY - 04-11-16 TIME=HH:MM - 12:53)
(MCX FILE - T)
(NC FILE - C:\USERS\RON\DOCUMENTS\MY MCAM2017\LATHE\NC\TOOLPATH GROUP-1.NC)
(MATERIAL - STEEL INCH - 1030 - 200 BHN)
G20
(TOOL - 97 OFFSET - 97)
(OD THREAD RIGHT  INSERT - NONE)
T9797
G97 S200 M03
G0 G54 X-2.1646 Z.3112
G76 X-1.7396 Z-1. I0. K.1125 D.0478 A59 E.07143
G28 U0. W0. M05
T9700
M30
%

[Rocketmachinist]

I was filling out the wrong fields