Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: vtx1029 on April 21, 2016, 08:36:46 AM

Title: Constant pulse generation?
Post by: vtx1029 on April 21, 2016, 08:36:46 AM

I've been doing some work with my 4th axis and rounding my stock takes forever via indexing. Is there a way to manually set a pulse stream so I can run my 4th axis constantly like a lathe and then run a normal program?

Title: Re: Constant pulse generation?
Post by: ger21 on April 21, 2016, 11:19:24 AM

Set up the 4th axis as a spindle. You'll then need to manually control the actual spindle.

Title: Re: Constant pulse generation?
Post by: iMisspell on April 21, 2016, 09:35:14 PM

Quote from: ger21 on April 21, 2016, 11:19:24 AM

Set up the 4th axis as a spindle. You'll then need to manually control the actual spindle.

At work i run a commercial cnc lathe which has live spindle tooling on the turret and a sub (2nd) spindle for part chucking; for the live tools we use M13/14 and sub-spindle M203/204.

Will the Mach software let a person write a macro which will in-turn "talk with" a vbscript to mimic something like that ?

Or could a person write a script with a loop in it that will just keep sending ("infinite") steps to the stepper motor in-till told different (could use a feed rate to control the speed) ?


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Title: Re: Constant pulse generation?
Post by: RICH on April 22, 2016, 05:47:57 AM

Note that a stepper is not a good choice for driving the index to mimic a spindle.
The gear ratio of the index is usually high and stepper torque drops off as the motor rpm increases.
Also if rpm indication is wanted, you will find that it is not linear over the range.
Just something to be aware of. Depends on range of desired index rpm.

FWIW,

RICH