[Jon.N.CNC]

Hi there,

I have mentioned this is other posts but unable to locate them. Here's a video of the issue:



Whenever I have none concentric arcs in toolpath regardless of feedrate I get this issue and that's as fast as it will go with these arcs.

The mc is the uc300, buffer size 0.3, look ahead 300 lines, cv stop angle 89.

Cpu usage low. It's wrecking bits cutting this slow, if you have any ideas I would be very greatful.

Thanks

Jon

[Jon.N.CNC]

Jerk issue 2 - YouTube

[OlfCNC]

On your video I don't see much,
Maybe you want to post some g-codes to let see the issue.

[Jon.N.CNC]

Just ran toolpath on other machine which has an i7 pc and 750ti graphics card and uc400, same jerky motion.

[Jon.N.CNC]

On your video I don't see much,
Maybe you want to post some g-codes to let see the issue.

Thanks for reading olf

(1)
(T4 D=6.35 CR=0. - ZMIN=-19. - FLAT END MILL)
G90 G94 G91.1 G40 G49 G17
G21

(2D CONTOUR1)
M5
M9
T4 M6
S5000 M3
G54
M8
G0 X98.296 Y120.85
G43 Z15. H4
Z7.5
G1 Z-5.865 F508.
Y120.857 Z-5.964
X98.295 Y120.881 Z-6.061
X98.294 Y120.919 Z-6.153
X98.292 Y120.971 Z-6.238
X98.29 Y121.036 Z-6.314
X98.288 Y121.111 Z-6.379
X98.285 Y121.196 Z-6.431
X98.282 Y121.288 Z-6.469
X98.279 Y121.385 Z-6.492
X98.276 Y121.484 Z-6.5
X98.256 Y122.119
G3 X97.601 Y122.734 I-0.635 J-0.02
G2 X97.492 Y122.732 I-0.112 J3.573 F1016.
G1 X96.219 Y122.731
G2 X96.161 I-0.003 J3.575
G1 X94.877 Y122.751
G2 X94.816 Y122.753 I0.056 J3.575
G1 X93.524 Y122.795
G2 X93.459 Y122.798 I0.116 J3.573
G1 X92.159 Y122.864
G2 X92.089 Y122.868 I0.181 J3.57
G1 X90.784 Y122.96
G2 X90.709 Y122.966 I0.251 J3.566
G1 X89.4 Y123.086
G2 X89.326 Y123.094 I0.326 J3.56
G1 X88.015 Y123.242
G2 X87.935 Y123.251 I0.401 J3.552
G1 X86.623 Y123.429
G2 X86.541 Y123.442 I0.481 J3.543
G1 X85.231 Y123.651
G2 X85.146 Y123.665 I0.563 J3.53
G1 X83.84 Y123.906
G2 X83.752 Y123.924 I0.649 J3.516
G1 X82.451 Y124.198
G2 X82.362 Y124.218 I0.737 J3.498
G1 X81.068 Y124.525
G2 X80.974 Y124.548 I0.825 J3.478
G1 X79.689 Y124.89
G2 X79.594 Y124.917 I0.92 J3.455
G1 X78.32 Y125.294
G2 X78.224 Y125.324 I1.014 J3.428
G1 X76.963 Y125.736
G2 X76.866 Y125.769 I1.11 J3.398
G1 X75.62 Y126.216
G2 X75.518 Y126.255 I1.207 J3.365
G1 X74.289 Y126.739
G2 X74.189 Y126.779 I1.31 J3.326
G1 X72.979 Y127.298
G2 X72.878 Y127.343 I1.409 J3.286
G1 X71.689 Y127.897
G2 X71.585 Y127.948 I1.51 J3.241
G1 X70.419 Y128.538
G2 X70.313 Y128.594 I1.614 J3.19
G1 X69.172 Y129.22
G2 X69.069 Y129.279 I1.72 J3.134
G1 X67.955 Y129.939
G2 X67.85 Y130.003 I1.823 J3.075
G1 X66.766 Y130.697
G2 X66.66 Y130.768 I1.927 J3.011
G1 X65.608 Y131.496
G2 X65.503 Y131.571 I2.034 J2.94
G1 X64.485 Y132.331
G2 X64.379 Y132.413 I2.138 J2.865
G1 X63.397 Y133.205

[ger21]

What are your settings for Linear error, linear addition, linear unify, and corner error?

And your using mm's, correct?

[Jon.N.CNC]

I can set the acceleration @ 2000mm/s/s which levels out the volicity to almost correct, but the jerks are still happening and get shed loads of vibration from it.

[geh7552]

Check to make sure "exact stop" isn't checked. If exact stop isn't checked then try changing CV stop angle to 180 and see if you have the same problem.

[Jon.N.CNC]

What are your settings for Linear error, linear addition, linear unify, and corner error?

And your using mm's, correct?

At defaults:

Linear error 0.03,
Linear addition 1,
Linear unify length 2,
Corner error 0.03


Its got to be something in the code, Does anyone have a uccnc pp for 360/inventor?

[Jon.N.CNC]

Check to make sure "exact stop" isn't checked. If exact stop isn't checked then try changing CV stop angle to 180 and see if you have the same problem.

Thanks for your input ger. Changing angle to 180 had no effect. In Cv Mode

Happening across 2 machines one ethernet controller one usb, one with ethernet controller the pc is very fast. Is anyone getting smooth motion in uccnc with i j arcs?

The jerks i believe correspond to the switch between g1 and g2

[OlfCNC]

Thanks. I'll have to go out now, will try to run your code tomorrow.

[ger21]

Where'd that terrible code come from?
1mm straight moves with 0.1mm arcs between them.

If you deleted the lines with the arcs, you probably wouldn't see the difference in the part, and it would probably run much smoother.

Set your linear error max to .1 and see if it helps?

[Jon.N.CNC]

Update. Just tried Pp with radius 'R' instead of I J. Same problem, Both machines.

(1)
(T4 D=6.35 CR=0. - ZMIN=-19. - FLAT END MILL)
G90 G94 G91.1 G40 G49 G17
G21


(2D CONTOUR1)
M5
M9
T4 M6
S5000 M3
G54
M8
G0 X98.296 Y120.85
G43 Z15. H4
Z7.5
G1 Z-5.865 F508.
Y120.857 Z-5.964
X98.295 Y120.881 Z-6.061
X98.294 Y120.919 Z-6.153
X98.292 Y120.971 Z-6.238
X98.29 Y121.036 Z-6.314
X98.288 Y121.111 Z-6.379
X98.285 Y121.196 Z-6.431
X98.282 Y121.288 Z-6.469
X98.279 Y121.385 Z-6.492
X98.276 Y121.484 Z-6.5
X98.256 Y122.119
G3 X97.601 Y122.734 R0.635
G2 X97.492 Y122.732 R3.575 F1016.
G1 X96.219 Y122.731
G2 X96.161 R3.575
G1 X94.877 Y122.751
G2 X94.816 Y122.753 R3.575
G1 X93.524 Y122.795
G2 X93.459 Y122.798 R3.575
G1 X92.159 Y122.864
G2 X92.089 Y122.868 R3.575
G1 X90.784 Y122.96
G2 X90.709 Y122.966 R3.575
G1 X89.4 Y123.086
G2 X89.326 Y123.094 R3.575
G1 X88.015 Y123.242
G2 X87.935 Y123.251 R3.575
G1 X86.623 Y123.429
G2 X86.541 Y123.442 R3.575
G1 X85.231 Y123.651
G2 X85.146 Y123.665 R3.575
G1 X83.84 Y123.906
G2 X83.752 Y123.924 R3.575
G1 X82.451 Y124.198
G2 X82.362 Y124.218 R3.575
G1 X81.068 Y124.525
G2 X80.974 Y124.548 R3.575
G1 X79.689 Y124.89
G2 X79.594 Y124.917 R3.575
G1 X78.32 Y125.294
G2 X78.224 Y125.324 R3.575
G1 X76.963 Y125.736

[Jon.N.CNC]

Where'd that terrible code come from?
1mm straight moves with 0.1mm arcs between them.

If you deleted the lines with the arcs, you probably wouldn't see the difference in the part, and it would probably run much smoother.

Set your linear error max to .1 and see if it helps?

This is inventor hsm pro. The tolerance for operation is set at 0.01

Will try changing linear error. But if uccnc does not support proper arcs how does a post processor create non concentric arcs without lots of small straight line moves. What am i missing.

[Jon.N.CNC]

Where'd that terrible code come from?
1mm straight moves with 0.1mm arcs between them.

If you deleted the lines with the arcs, you probably wouldn't see the difference in the part, and it would probably run much smoother.

Set your linear error max to .1 and see if it helps?

Nope like you say ger, its the way the code is written no amount of cv setting seems to do much at all.

Set cv error 0.1, corner error 0.1, Operation tolerance 0.1, Pp Minimum circular radius 0.1. No change.

[ger21]

Your code is 95% straight moves, with very, very small arcs connecting them. It would yield the exact same part if it was just straight lines.
It's really very bad code. Rather than smoothly running along the straight lines, and having CV mode blend them together, the tiny arcs are causing it to try to stay closer to the commanded path, which means it must slow down to do that.

I suspect that the issue lies within the 4 tolerance settings that I mentioned.

[ger21]

Do you have backlash comp enabled?

[Jon.N.CNC]

Do you have backlash comp enabled?

Yes 0.03, comp accel 500mm/s/s.

Fixed. You have to have smoothing ticked when creating the operation in Cam. I need to be ticking that box for every operation i make. Great. Shouldn't have assumed that setting the tolerance higher would achieve the same result.

with smoothing:

(1)
(T4 D=6.35 CR=0. - ZMIN=-19. - FLAT END MILL)
G90 G94 G91.1 G40 G49 G17
G21


(2D CONTOUR1)
M5
M9
T4 M6
S5000 M3
G54
M8
G0 X98.296 Y120.85
G43 Z15. H4
Z7.5
G1 Z-5.865 F508.
Y120.857 Z-5.964
X98.295 Y120.881 Z-6.061
X98.294 Y120.919 Z-6.153
X98.292 Y120.971 Z-6.238
X98.29 Y121.036 Z-6.314
X98.288 Y121.111 Z-6.379
X98.285 Y121.196 Z-6.431
X98.282 Y121.288 Z-6.469
X98.279 Y121.385 Z-6.492
X98.276 Y121.484 Z-6.5
X98.256 Y122.119
G3 X97.601 Y122.734 I-0.635 J-0.02
G1 X97.492 Y122.732 F1016.
G2 X69.025 Y129.195 I-1.929 J57.431
X54.951 Y143.935 I17.359 J30.664
X58.544 Y168.105 I21.587 J9.142
X79.284 Y181.94 I31.211 J-24.326
X95.649 Y184.853 I18.402 J-55.943
G1 X115.447 Y185.475
G3 X135.102 Y191.001 I-11.468 J78.505
G1 X138.381 Y192.249
X144.949 Y194.917
G2 X172.876 Y202.624 I39.98 J-90.419
X205.553 Y196.272 I-0.482 J-89.7
X234.881 Y179.319 I-26.03 J-78.874
X244.212 Y164.595 I-26.189 J-26.915
X239.528 Y141.466 I-25.704 J-6.833
X222.901 Y126.155 I-44.126 J31.236
X179.37 Y110.003 I-57.722 J88.825
X154.317 Y113.681 I-2.203 J72.154
G1 X148.834 Y115.413
X143.355 Y117.156
X137.879 Y118.909
X132.406 Y120.672
G3 X117.399 Y123.356 I-21.358 J-76.145
G1 X97.601 Y122.734
G2 X97.448 Y122.832 I-0.005 J0.162
G3 X97.295 Y122.932 I-0.152 J-0.066
G2 X69.128 Y129.369 I-1.779 J57.06
X55.136 Y144.014 I17.224 J30.464
X58.701 Y167.981 I21.398 J9.065
X79.343 Y181.748 I31.052 J-24.199
X95.656 Y184.653 I18.343 J-55.751
G1 X115.465 Y185.276
G3 X135.174 Y190.815 I-11.48 J78.683
G1 X138.455 Y192.063
X145.025 Y194.732
G2 X172.886 Y202.424 I39.909 J-90.25
X205.483 Y196.085 I-0.49 J-89.5
X234.739 Y179.178 I-25.965 J-78.696
X244.016 Y164.543 I-26.03 J-26.757
X239.365 Y141.583 I-25.482 J-6.789
X222.793 Y126.324 I-43.954 J31.107
X179.355 Y110.203 I-57.615 J88.656
X154.376 Y113.872 I-2.188 J71.955
G1 X148.892 Y115.605
X143.411 Y117.348
X137.934 Y119.101
X132.46 Y120.865
G3 X117.403 Y123.556 I-21.414 J-76.355
G1 X97.595 Y122.934
X97.492 Y122.932
X97.295
G2 X97.145 Y123.032 I0. J0.162
G3 X96.995 Y123.132 I-0.15 J-0.063
G2 X69.232 Y129.544 I-1.545 J56.617
X55.321 Y144.092 I17.074 J30.252
X58.859 Y167.857 I21.207 J8.989
X79.401 Y181.557 I30.894 J-24.071
X95.662 Y184.453 I18.284 J-55.557
G1 X115.482 Y185.076
G3 X135.246 Y190.628 I-11.491 J78.862
G1 X138.53 Y191.878
X145.1 Y194.547
G2 X172.895 Y202.224 I39.84 J-90.082
X205.413 Y195.898 I-0.499 J-89.299
X234.597 Y179.037 I-25.901 J-78.518
X243.442 Y165.695 I-27.228 J-27.654
X239.97 Y142.816 I-24.497 J-7.985
X222.681 Y126.503 I-44.104 J29.422
X179.339 Y110.405 I-57.399 J88.145
X154.435 Y114.064 I-2.196 J71.619
G1 X148.949 Y115.797
X143.467 Y117.539

Thanks for your help Ger.. Noticing the small moves pushed me the right direction.

[ger21]

Try the original code with backlash comp turned off.

Also, make sure you close and restart UCCNC after making any changes.

[Jon.N.CNC]

Try the original code with backlash comp turned off.

Also, make sure you close and restart UCCNC after making any changes.

Just tried it on the i7/uc400 machine, opened and closed. No avail. jerking the same. So there we go, I think you would need a machine capable of instant acceleration to run that code without jerking.

Happy i now know ' you have to use smoothing for cutting arcs in hsm'

Interesting though the higher the smoothing value the more small straight moves it generates over arcs so the jerking starts to creep back in. 0.03 seems to be the fastest setting with the least amount of transitions between arcs and xy moves. Still get a deceleration/acceleration at each transition though. Angle is a continuous curve so wouldnt meet the cv stop angle. So still something that doesnt make sense here.

Smoothest setting for linear error seems to also be 0.03, 0.1 or 0.01 it runs at a less constant velocity. Coincidence or could it be that the linear error needs to match the cam smoothing setting.