Incremental arcs and Break arcs into lines

I have a thread mill path that I'm playing with. I need to break the arcs into lines for an old controller. The arcs are incremental. I've been able to break arcs that are absolute but the incremental arcs don't break properly. I tried setting the arc centers to absolute without success. Is there a way to convert incremental paths to absolute prior to breaking?

This is the test code:
G90 G00 X0 Y0
G91 G00 X0 Y0 Z-0.379
G01 G41 D60 X0.0148 Y-0.0802 Z0 F18.59
G91 G03 X0.0802 Y0.0802 Z0.0038 R0.0802 F18.59
G91 G03 X0 Y0 Z0.0417 I-0.0950 J0 F61.97
G91 G03 X-0.0802 Y0.0802 Z0.0038 R0.0802
G00 G40 X-0.0148 Y-0.0802 Z0
G90 G00 Z1.0000

Yes you can convert coordinates to absolute in NcPlot 2.20
Highlight the code that your editing (select the whole G91 string) then go to Tools\Convert Coordinates to ABS then change that G91 to G90 then you should be able to break arcs into lines. After finishing you can change the code back to incremental
Highlight the code that your editing (select the whole G90 string) then go to Tools\Convert Coordinates to INC then change that G90 to G91

you code may need to be cleaned up first i had to get rid of feed rates and z height save file under different name and open both under file\compare file. Then edit and add back needed feed rates and z height also if your controller doesn’t need redundant G moves (G00,G01,G02,G03) clean them up to

Still can't quite get this to work. This is a helix so I can't really strip the z values but the z values are converting to abs fine.

This is after conversion:
G90 G00 X0 Y0
G00 X0 Y0 Z-0.379
G01 G41 D60 X0.0148 Y-0.0802 Z-0.379 F18.59
G03 X0.095 Y0 Z-0.3752 R0.0802 F18.59
G03 X0.095 Y0 Z-0.3335 I-0.0950 J0 F61.97
G03 X0.0148 Y0.0802 Z-0.3297 R0.0802
G00 G40 X0 Y0 Z-0.3297
G90 G00 Z1.0000

This appears to plot fine but when I convert the arcs to lines it breaks. Clearly I'm missing a step. Do you see anything obvious?

Arggg... sorry about that. I thought I fixed the breaking of helical arcs but there is still something broken. Here is your code (in absolute):

G00 X0 Y0
G00 X0 Y0 Z-0.379
G01 G41 D60 X0.0148 Y-0.0802 Z-0.379 F18.59
G01F18.59X0.0261Y-0.0794Z-0.3787
X0.0372Y-0.077Z-0.3783
X0.0478Y-0.0731Z-0.378
X0.0577Y-0.0677Z-0.3776
X0.0669Y-0.061Z-0.3773
X0.0749Y-0.0531Z-0.3769
X0.0818Y-0.0441Z-0.3766
X0.0873Y-0.0342Z-0.3763
X0.0914Y-0.0236Z-0.3759
X0.094Y-0.0126Z-0.3756
X0.095Y-0.0013Z-0.3752
X0.095Y0Z-0.3752
G01F61.97X0.0942Y0.0123Z-0.3743
X0.0918Y0.0244Z-0.3735
X0.0879Y0.0361Z-0.3726
X0.0825Y0.0471Z-0.3718
X0.0757Y0.0574Z-0.3709
X0.0676Y0.0667Z-0.37
X0.0584Y0.0749Z-0.3692
X0.0482Y0.0819Z-0.3683
X0.0372Y0.0874Z-0.3674
X0.0256Y0.0915Z-0.3666
X0.0135Y0.094Z-0.3657
X0.0013Y0.095Z-0.3649
X-0.0111Y0.0944Z-0.364
X-0.0232Y0.0921Z-0.3631
X-0.0349Y0.0884Z-0.3623
X-0.046Y0.0831Z-0.3614
X-0.0564Y0.0764Z-0.3606
X-0.0658Y0.0685Z-0.3597
X-0.0741Y0.0594Z-0.3588
X-0.0812Y0.0493Z-0.358
X-0.0869Y0.0384Z-0.3571
X-0.0911Y0.0268Z-0.3562
X-0.0938Y0.0148Z-0.3554
X-0.095Y0.0025Z-0.3545
X-0.0945Y-0.0098Z-0.3537
X-0.0924Y-0.022Z-0.3528
X-0.0888Y-0.0337Z-0.3519
X-0.0837Y-0.0449Z-0.3511
X-0.0772Y-0.0554Z-0.3502
X-0.0694Y-0.0649Z-0.3494
X-0.0604Y-0.0734Z-0.3485
X-0.0504Y-0.0806Z-0.3476
X-0.0395Y-0.0864Z-0.3468
X-0.028Y-0.0908Z-0.3459
X-0.016Y-0.0936Z-0.345
X-0.0038Y-0.0949Z-0.3442
X0.0086Y-0.0946Z-0.3433
X0.0207Y-0.0927Z-0.3425
X0.0326Y-0.0892Z-0.3416
X0.0438Y-0.0843Z-0.3407
X0.0544Y-0.0779Z-0.3399
X0.064Y-0.0702Z-0.339
X0.0726Y-0.0613Z-0.3382
X0.0799Y-0.0514Z-0.3373
X0.0859Y-0.0407Z-0.3364
X0.0904Y-0.0292Z-0.3356
X0.0934Y-0.0172Z-0.3347
X0.0949Y-0.005Z-0.3339
X0.095Y0Z-0.3335
G01X0.0942Y0.0113Z-0.3332
X0.0918Y0.0224Z-0.3328
X0.0879Y0.033Z-0.3325
X0.0825Y0.0429Z-0.3321
X0.0758Y0.0521Z-0.3318
X0.0679Y0.0601Z-0.3314
X0.0589Y0.067Z-0.3311
X0.049Y0.0725Z-0.3308
X0.0384Y0.0766Z-0.3304
X0.0274Y0.0792Z-0.3301
X0.0161Y0.0802Z-0.3297
X0.0148Y0.0802Z-0.3297
G00 G40 X0 Y0 Z-0.3297
G00 Z1.0000

I'll get this fixed ASAP.

Thanks,
Scott

Quote:

---

Originally Posted by MetLHead

Arggg... sorry about that. I thought I fixed the breaking of helical arcs but there is still something broken. Here is your code (in absolute):

---

Thanks Scott! I thought I was doing something wrong.

OK, this is fixed now. I just released NCPlot v2.21 which includes your fix plus a few other improvements.

Thanks,
Scott

Thanks for the fix Scott. Works great. :)

Scott,

I think there may yet be an issue with the incremental helical arcs. With the code below the arcs are shifted when broken into lines. If I create this routine as absolute the arcs break fine. Something is still weird with the inc arcs.

This a drill and thread mill routine

N5 G00 G53 G40 G60 G90 D0 Z+0.0000
N10 G80
N15 T1 M06
N20 G54 X+0.0000 Y+0.0000 M08
N25 Z+0.039370 D1 S10729 M03
; ( PRE-DRILLING )
N30 G01 Z-0.039370 F42.24
; ( DRILLING )
N35 G01 Z-0.501378 F126.72
N40 G00 Z+0.0000
N45 G00 Z-0.462008
N50 G01 Z-0.748346
N55 G00 Z+0.0000
; ( CONVENTIONAL MILLING )
N60 G00 Z-0.636102
N65 G01 G91 G42 G64 X+0.0000 Y+0.116220 F59.14 ; (F8.69)
N70 G02 X+0.000000 Y-0.272480 I+0.0000 J-0.136240 Z-0.008333
N75 G02 X+0.0000 Y+0.000000 I+0.0000 J+0.156260 Z-0.055551 ; (F15.15)
N80 G02 X+0.000000 Y+0.272480 I+0.0000 J+0.136240 Z-0.008333 F147.84 ; (F21.72)
N85 G00 G40 G60 X+0.000000 Y-0.116220
N90 G00 G90 Z+0.039370
N95 G00 G53 G40 G90 D0 Z+0.0000 M95
N100 M30

The problem here seems to be the comment at the end of the line, or rather the problem is with the way NCPlot updates the block:

G01; (F15.15)X-0.0158Y0.0008Z-0.0009

The X,Y,Z,I,J,K values are removed from the block and new values are tacked on to the end of whatever is left. In this case when the semicolon ";" is encountered NCPlot takes this to be the end of the line and so this block is being ignored. If you remove the "; (F15.15)" it will plot correctly. So I think the solution is going to be a change to the way I update these blocks.

Thanks,
Scott

Quote:

---

Originally Posted by MetLHead

G01; (F15.15)X-0.0158Y0.0008Z-0.0009

---

Boy I feel dumb. I looked at the converted code but just couldn't see it. Your right, once I remove the comments it works perfectly. Thanks again.