Threading Tool Path in Lathe

[alfagt]

If you write a threading tool path, internal or External, there are 3 tabs in mastercam; defining tool, shape of threads and cut parameteres. In the cutting prameteres there is a leadin angle which when you post G code it appears in the G76 line where in manual programming is the profile angle between to threads. The 60 Degree angle which in required for the UNC and UNF threads. I wonder if this value has to be put there or this lead in angle is just an approch to the the threads? I am a little confuse. Anybody has an answer?

[uncle_dolan]

Hi and welcome to the forum!

 

I believe that the lead-in angle that you are talking about is just that...for most threads I do not see that there is much use for this, and mine is left at default of 29 degrees... If you were starting the thread part way along your bar however, you would want it to lead in at an angle rather than straight across or plunging. HTH Brendan

[alfagt]

Hi and welcome to the forum!

 

I believe that the lead-in angle that you are talking about is just that...for most threads I do not see that there is much use for this, and mine is left at default of 29 degrees... If you were starting the thread part way along your bar however, you would want it to lead in at an angle rather than straight across or plunging. HTH Brendan

 

thank you brendon. When I calculate manually yhte treading toolpath and writ a program I use a G76 code. for example:

 

G76P110060Q0100R0.0005

 

in the P function the 60 stnads for 60DEG angle of the toll and thread profile. It is stange that when I did the semin mastercam and post the codes it appears as 29 instead 60 and that conceren me. I am agree with you regarding leadin angle.