4th Axis post question

[RandleXX]

Is it possible to change a post to output a rotation from 0 up to 180 deg. then after 180 post -179 decreasing down to -1 and back to 0. Right now, I set the post to reset to 0 at 360 deg., but I need it to output negative numbers to rotate the backwards direction to keep larger parts that cannot rotate a full 360 from crashing. I have been manually changing the programs to get this to work, for example, I change all A270. to A-90. and this works great, but it is time consuming.

 

here is a sample of my current post

 

# --------------------------------------------------------------------------

# Rotary Axis Settings

# --------------------------------------------------------------------------

vmc : 1 #0 = Horizontal Machine, 1 = Vertical Mill

rot_on_x : 1 #Default Rotary Axis Orientation, See ques. 164.

#0 = Off, 1 = About X, 2 = About Y, 3 = About Z

rot_ccw_pos : 0 #Axis signed dir, 0 = CW positive, 1 = CCW positive

index : 0 #Use index positioning, 0 = Full Rotary, 1 = Index only

ctable : 5 #Degrees for each index step with indexing spindle

use_frinv : 0 #Use Inverse Time Feedrates in 4 Axis, (0 = no, 1 = yes)

maxfrdeg : 2000 #Limit for feed in deg/min

maxfrinv : 999.99#Limit for feed inverse time

frc_cinit : 1 #Force C axis reset at toolchange

ctol : 360 #Tolerance in deg. before rev flag changes

ixtol : .01 #Tolerance in deg. for index error

frdegstp : 10 #Step limit for rotary feed in deg/min

 

Thank You.

Randle Domico

[JG]

Randle,

Make sure your plane definition takes the short route in M/C (I use cplane,rotate), then the post should follow with the required output.

 

J.G.

 

BTW if the output dosen't match, what machine and post?

[Mike Whitten CAD/CAM Contractors]

Many machines have M codes so make it reach the destination via a specific direction.

 

Mike

[RandleXX]

Machine

[RandleXX]

Macine is Okuma w/osp5020 control

Post is customized MPOKUMA

 

thanks

RAndle

[Mike Whitten CAD/CAM Contractors]

You must look in the book.

[Glenn Stephens. from CCCS]

You could force the output to -179 to +180. This shouldn't be too difficult, and shouldn't screw up anything else unless you do a full rotary toolpath that crosses the 180 deg line.

[Jean-Simon]

I do edit my code often with M15 (clockwise) and M16 (ccw) to avoid that kind of thing and works great but needs a little editing but quite fast.

 

Simon

[Mike Whitten CAD/CAM Contractors]

The mpmaster looks like it may already have code for this. I found this in the post:

 

# Table rotation direction

# Table rotation direction, index

sindx_cw M220 #Rotate CW code

sindx_ccw M210 #Rotate CCW code

sindx_mc #Target for string

 

fstrsel sindx_cw indx_mc sindx_mc

 

 

Mike

[Mick]

Get the MPMaster_Okuma post. Its set up perfectly. I've used this with great success on an Okuma MX55VB with a rotary axis (U100M control)

Your dealer should be able to hook you up

[Allan Brown]

Your dealer will need to email me to request it.