Need Help!- turning a 1/8 npt on a lathe

[metalmansteve]

Can someone give me a sample program for a male 1/8 npt?

I've got a faunc oi-tb control.

1st time is always the hardest!

Thanks in advance for your help

Best,

Steve

[CNCRim]

Not sure what lathe you have, but I will ahead anyway. Program for single point threat cutter. It's only an sample it's come off of my head, I had been so long the last time I did NPT now I forgot the what is the angle for it and what is the minor diameter and what is major diameter ....... so check Machinist Handbook and adjust accordingly OK.

G00 X.65.Z.1 M3
G92X.62Z-.6I.12 (I is the angle of the tape)
X.61
X.6
x59
...
...
G0Z.1

[g-codeguy]

Finish turn 1/64R

G1X.2777Z0F.003
G3X.3074Z-.0061R.021
G1X.3953Z-.0501
X.405Z-.2066
Z-?

Finish turn 1/32R

G1X.2477Z0F.003
G3X.2987Z-.0105R.036
G1X.3949Z-.0586
X.405Z-.2214
Z-?

G76 2-block

X.44Z.3
G76P000155Q30R.001
G76X.361Z-.5P296Q100R-.0249F.03704

G76 1-block

X.44Z.3
G76X.361Z-.5I-.0249K.0296D100F.03704A55P?

P is an option (as is I) which determines how the thread is cut. Choices are 1 through 4.

P1= one-side cutting with constant cutting amount
P2= zigzag cutting with constant cutting amount
P3= one-side cutting with constant cutting depth
P4= zigzag cutting with constant cutting depth

P1 is default.

Or you can use G32 which is the most powerful threading cycle, but requires a lot more on your part to program. Unlike the G92 cycle, you can program any kind of compound infeed you desire. With the G32 you could program a 1/8NPT on the front, change the G32 block to cut a straight thread (at any pitch) and change directions at the end of that for another type of thread if need be.