NPT THREADS SINGLE POINT ON LATHE

[Mike@Dive Lab Inc.]

Hi, I'm trying to cut 1/4-18 npt on a HAAS lathe.This is the first time doing so, everything seems ok in mastercam. No matter what I do, it cuts way to deep, and way to many passes, 29 to be exact. Could it be the machine settings? this is what i'm getting

 

G76 X.433 Z-.401 I-.0146 K .0444 D.0063 30

 

Thanks,

MIke

[[email protected]]

u meen u want to control the depth of cut ?

[mrainey]

If K is the pitch, shouldn't it be .0556 ?

[Andy]

Increase D to limit the number of passes.

Increase the tool offset to move the tool away from the work to reduce depth of thread or change X to a larger number.

 

X is the finish root diameter.

D is the first pass depth of cut. (and is used to calculate the remaining pass depths.

I is the taper amount in the .401 length.

 

In my Mori lathe the pitch would be F.0555

and K would be the depth of thread (which tells the tool where to start calculating the first pass cutting depth).

I do not see the pitch in your code. Should be .0555

[Mike@Dive Lab Inc.]

I ended up getting it, by doing pretty much what you said I did have the pitch I just left it out above. I was getting messed up in the final x dia. I think Mastercam does it 2 ways,you can get it from the big or small end of the taper

 

Thanks for the help

MIke

[Andy]

After forty years it is never easy!

Cheers