4-axis postprocessor problem...
4-axis postprocessor problem...
(OP)
I have problem with 4-axis post. When I mill cylinder (for example) with variable contour method I have the following :
N0088 B0.0
N0089 Y9.563
N0090 B112.5
N0091 Y9.562 B120.
N0092 Y9.563 B135.
N0093 Y9.562 B150.
N0094 Y9.563 B165.
N0095 Y9.562 B180.
N0096 B210.
N0097 Y9.563 B270.
As you can see I have a jitter on Y coordinate
Must be:
N0088 B0.0
N0089 Y9.563
N0090 B180
N0091 B270
How can I avoid of this jitter?





RE: 4-axis postprocessor problem...
--
Bill
RE: 4-axis postprocessor problem...
RE: 4-axis postprocessor problem...
What is the Intol / Outtol set to?
For 4 axis work I will usually set the tools axis as towatd line and use the centerof rotation. Then set the projection vector to tool-axis.
In Post builder you can remove the redundent 4th-axis moves by including the custom command pb_cmd_combine_rotary.tcl
John Joyce
Tata Technologies
1675 Larimer St.
Denver, CO
www.myigetit.com
NX3,4,5,6 Solid Works, Pro/e, Solid Edge
RE: 4-axis postprocessor problem...
I defined tool axis and projection as you had explained before (toward line -> center of rotation ), also I used pb_cmd_combine_rotary.tcl to reduce number of rotary coordinates.
Intol / Outtol set to default = 0.03
I uploaded part example(NX6), post and post output. Please take a look.
RE: 4-axis postprocessor problem...
You must remove the "PB_CMD_combine_rotary_check" from the linear move event.
I have verified this. you will NOT get combined blocks if the event is there. Read the instructions carefully.
As far as your file goes, Try replacing the drive "solid" with something else...
I modeled a hole thru the part and used that as a drive surface. It sometimes makes a difference.
Also, I got better results using a ballnose endmill.
Good luck
J
RE: 4-axis postprocessor problem...
"
# This function will only work with NX3 or later.
# Add the follow line (without the #) to the custom command
# PB_CMD_before_motion.
# PB_CMD_combine_rotary_check
"
Where must I place these two lines? It's not quite clear from
instructions.
RE: 4-axis postprocessor problem...
It's actually only one line you are placing.
Read it like this...
This function will only work with NX3 or later. Add the follow line (without the #) to the custom command PB_CMD_before_motion.
# PB_CMD_combine_rotary_check
You just add the one line.
J