[zaebis]

Folks, I keep seeing guys on youtube showing off how they use mill as a lathe loading stock in the collet (obviously small diameter) and lathe cutting tool in a vice. Then running it as though it was a lathe. I have done that as well with great success except cutting threads. I use Mach3 as a controller software for my mill and its lathe wizards also work fine on milling Mach3 profile on my mill. The only thing that doesnt work is threading. Lathe threading wizard spits out something like

G76 X0.4 Z-1 Q1 P0.05 J0.006 L45 H0.022 I29 C0.025 B0.0001 T0

which obviously is not recognized in Mach3 milling profile so cant be executed on my mill.

I would like to know alterrnatives to this G76 cycle that can be executed on a mill to cut threads (stock in a spindle, cutting tool in a vice).

p.s. yes I have stable RPMs on a spindle.

[txcncman]

You probably want something like a G87 - Bore In, Manual Retract cycle.

[Geof]

You can do it if your machine has the G84 tapping canned cycle:

http://www.cnczone.com/forums/haas_m...gle_point.html

[txcncman]

The G84 is the perfect answer. Don't try thread milling on a mill.

[Geof]

Perfectly correct (for once) the G84 does run the tool backwards. Did you bother checking my link to see that possibility was mentioned. It was more of an academic exercise to see if it was possible to cut a thread on a piece of material held in the spindle of a milling machine. It is. Is it practical? Probably not. Cheapness has nothing to do with it, a thread mill tool is not applicable to the operation that was done.

[txcncman]

Perfectly correct (for once) the G84 does run the tool backwards. Did you bother checking my link to see that possibility was mentioned. It was more of an academic exercise to see if it was possible to cut a thread on a piece of material held in the spindle of a milling machine. It is. Is it practical? Probably not. Cheapness has nothing to do with it, a thread mill tool is not applicable to the operation that was done.

I stand corrected.

[angelw]

You can do it if your machine has the G84 tapping canned cycle:

http://www.cnczone.com/forums/haas_m...gle_point.html

Hi Geof,
I did take the time to look at your other thread, but it doesn't answer the question that comes to my mind, that being, unless the control is equipped with rigid tapping, would you not get an error in the thread lead at the end of the thread where the spindle and Z slide direction is reversed, and hence the requirement for an axial floating tap holder when tapping with the non rigid tapping G84 cycle.

Regards,

Bill

[Geof]

Good point. My machine does have rigid tapping, actually repeat rigid tapping and I completely overlooked that this is an option not standard.