Machsupport Forum

G-Code, CAD, and CAM => G-Code, CAD, and CAM discussions => Topic started by: Hafco on March 06, 2011, 09:01:08 PM

Title: G76 Threading problem
Post by: Hafco on March 06, 2011, 09:01:08 PM

Good afternoon, i am having some problems with a threading code, when i post the code from the wizard it writes the code produces the toolpath no problem, however when you hit cycle start the machine moves to the correct position chuck starts up and when it gets to the line of code with the g76 and the cutting data it doesn't do anything the chuck keeps turning but it doesn't move,

what am i doing wrong

any help is much appreciated

thanx

Title: Re: G76 Threading problem
Post by: RICH on March 07, 2011, 05:40:18 AM

Hafco,
It is stopping at that line and waiting for the index signal to tell Mach to begin the threading.
Test that your index is working properly, see Threading on the Lathe Write up, Axis test / page 9.
Make sure your configuration is correct.
RICH

Title: Re: G76 Threading problem
Post by: sivtek on October 29, 2011, 01:43:50 PM

Hi RICH

I have the same problem as Hafco, stops at G76. I use a Proximity Sensor and I get a signal when I turn the spindle slow, but when I get up to speed (300 to 1000rpm) the signal is getting unstable. (This prove that the index is working)?
You mention "Threading on the Lathe Write up, Axis test / page 9", where can I find this?
This is my first try withe the Lathe, a Myford converted to CNC as described in Model Engineers Workshop. (I run the lathe spindle manually).
Hope you can help.

Regards
Johannes Line

Title: Re: G76 Threading problem
Post by: RICH on October 29, 2011, 05:33:44 PM

Johannes,

Quote

Threading on the Lathe WriteUp

.......You will find the latest Manual in Members Docs.

Quote

the signal is getting unstable

Your unloaded spindle rpm should not vary by more than 1 or 2 rpm. The more stable the better and is  key to producing good threads.
Make sure you have spindle speed averaging checked and also look at the index debounce settings in configuration. Mach is trying to see a stable
rpm for a period of time and if not the thread cycle may not start.

RICH

Title: Re: G76 Threading problem
Post by: sivtek on October 30, 2011, 04:57:42 AM

RICH

Thanks for your help. I found the Manual and read it - good. I unchecked the "Disable Spindle Relays" and now it WORKS. May have to do some finetuning before I can make a good tread.
Thanks

Johannes

Title: Re: G76 Threading problem
Post by: RICH on October 30, 2011, 05:59:11 AM

Glad you got it fixed. Let us know how how your threading works.
RICH