Break Angle


Results 1 to 8 of 8

Thread: Break Angle

  1. #1
    Member
    Join Date
    May 2017
    Location
    United States
    Posts
    78
    Downloads
    0
    Uploads
    0

    Default Break Angle

    Cutting a pocket, using Fusion 360 which creates the g code. The pocket is intricate, problem is it seems to being small circles in the tight corners and the machine is jerking slightly as if it is stopping then starting not a smooth movement. I have my break angle set at 20. I think this may be a break angle issue? Is 20 low or high what is the low and high range for the break angle? This is on a cnc router. thanks for any help and info. Joe

    Similar Threads:


  2. #2
    Member deadlykitten's Avatar
    Join Date
    Jun 2015
    Location
    Antarctica
    Posts
    3195
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    hy program is succumbing the machine : the geometrical entity is too short, thus programmed feed can not be reached

    if you wish to prevent this, you have to simulate the motion by using the cnc algorithms inside the simulation software, that should create a map of motion loss, and adjust as necessary ... auto adjusting would be real nice

    to smooth out the movement :
    ... increase the length of the geometrical entities
    ... and / or
    ... decrease the tolerance of the machine, activate some dynamic control ( requires a nice cnc controler )

    kindly long live fusion !

    the human body has enough iron to make a nail ... i can also make the hammer :) i mean a plastic hammer


  3. #3
    Member TomKerekes's Avatar
    Join Date
    May 2006
    Location
    USA
    Posts
    3502
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    Hi Joe,

    Cutting a pocket, using Fusion 360 which creates the g code. The pocket is intricate, problem is it seems to being small circles in the tight corners and the machine is jerking slightly as if it is stopping then starting not a smooth movement. I have my break angle set at 20. I think this may be a break angle issue? Is 20 low or high what is the low and high range for the break angle?
    You might try Break Angle of 179 degrees which "rounds" all corners within the Corner Tolerance and should avoid all exact stops.

    Can you create a small GCode fragment to demonstrate the issue? Also please post all your settings.

    Regards
    TK http://dynomotion.com


  4. #4
    Member
    Join Date
    May 2017
    Location
    United States
    Posts
    78
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    Quote Originally Posted by TomKerekes View Post
    Hi Joe,

    You might try Break Angle of 179 degrees which "rounds" all corners within the Corner Tolerance and should avoid all exact stops.

    Can you create a small GCode fragment to demonstrate the issue? Also please post all your settings.
    Below settings and part of the g code generated by Fusion 360 thanks for the help, Joe

    Settings
    Break Angle 20
    Look Ahead 3
    Collinear Tolerance .0005
    Clearance Tolerance .003
    Facet Angle 1
    Arcs to Segments checked

    ch0 is X axis Vel = 10160 Accel = 30480
    ch1 and ch7 = Y axis Vel 10160 Accel = 20320
    ch2 = Z axis Vel = 10160 Accel 30480

    %
    (test)
    (1/4 2 Flute End Mill Z Top of piece off use 3/4 block X/Y bottom left stock)
    N10 G90 G94
    N15 G17
    N20 G20


    (2D Pocket2)
    N25 M9
    N30 T2 M6
    N35 S13600 M3
    N40 M9
    N50 G0 X2.2549 Y5.5434
    N55 G0 Z1.4
    N60 G1 Z0.2 F43.3
    N65 G1 Z-0.1
    N70 G1 X2.254 Y5.5437
    N75 G2 X2.222 Y5.5531 I0.1573 J0.5938
    N80 G3 X2.2014 Y5.5457 I-0.0055 J-0.017
    N85 G3 X2.1448 Y5.4478 I1.0233 J-0.6561
    N90 G3 X2.1487 Y5.4263 I0.0159 J-0.0082
    N95 G2 X2.1725 Y5.4036 I-0.4114 J-0.4562
    N100 G3 X2.1849 Y5.405 I0.0057 J0.0056
    N105 G1 X2.3206 Y5.6158
    N110 G3 X2.3154 Y5.628 I-0.0067 J0.0043
    N115 G2 X2.1869 Y5.6704 I0.0962 J0.507
    N120 G3 X2.167 Y5.6654 I-0.007 J-0.0144
    N125 G3 X2.024 Y5.4177 I1.081 J-0.7892
    N130 G3 X2.0296 Y5.398 I0.0147 J-0.0065
    N135 G2 X2.131 Y5.3075 I-0.29 J-0.4269
    N140 G3 X2.1437 Y5.3084 I0.0061 J0.0052
    N145 G1 X2.3985 Y5.7028
    N150 G3 X2.3921 Y5.7151 I-0.0067 J0.0043
    N155 G2 X2.1638 Y5.7959 I0.0194 J0.4177
    N160 G3 X2.1453 Y5.7937 I-0.0081 J-0.011
    N165 G3 X2.0057 Y5.5934 I1.0761 J-0.8987
    N170 G3 X1.902 Y5.3724 I1.2443 J-0.7184
    N175 G3 X1.9094 Y5.3552 I0.0128 J-0.0047
    N180 G2 X2.0942 Y5.1968 I-0.1679 J-0.383
    N185 G3 X2.1076 Y5.1966 I0.0067 J0.0043
    N190 G1 X2.538 Y5.8213
    N195 G3 X2.5284 Y5.8333 I-0.0066 J0.0045
    N200 G2 X2.3587 Y5.8147 I-0.118 J0.2928
    N205 G2 X2.1585 Y5.9337 I0.0525 J0.3162
    N210 G3 X2.1423 Y5.9345 I-0.0084 J-0.0066 F10.82
    N215 G3 X1.7786 Y5.3045 I1.1201 J-1.0667 F43.3
    N220 G3 X1.7874 Y5.291 I0.0102 J-0.003 F10.82
    N225 G2 X1.9906 Y5.1771 I-0.0444 J-0.3175 F43.3
    N230 G2 X2.0588 Y5.0241 I-0.2438 J-0.2005
    N235 G1 X2.1744 Y4.3531
    N240 G2 X2.1722 Y4.3461 I-0.0079 J-0.0014
    N245 G2 X2.1487 Y4.3237 I-0.4349 J0.4339
    N250 G3 X2.1448 Y4.3022 I0.012 J-0.0133
    N255 G3 X2.2014 Y4.2043 I1.0798 J0.5581
    N260 G3 X2.222 Y4.1969 I0.0151 J0.0097
    N265 G2 X2.2539 Y4.2063 I0.1894 J-0.5844
    N270 G3 X2.259 Y4.2177 I-0.0021 J0.0077
    N275 G1 X2.1441 Y4.4409
    N280 G3 X2.1309 Y4.4424 I-0.0071 J-0.0037
    N285 G2 X2.0296 Y4.352 I-0.3913 J0.3365
    N290 G3 X2.024 Y4.3323 I0.009 J-0.0133
    N295 G3 X2.167 Y4.0846 I1.224 J0.5415
    N300 G3 X2.1869 Y4.0796 I0.0129 J0.0095
    N305 G2 X2.3154 Y4.122 I0.2247 J-0.4646
    N310 G3 X2.3211 Y4.1335 I-0.0015 J0.0079
    N315 G1 X2.1082 Y4.5527
    N320 G3 X2.0943 Y4.5533 I-0.0071 J-0.0036
    N325 G2 X1.9094 Y4.3948 I-0.3529 J0.2244
    N330 G3 X1.902 Y4.3776 I0.0055 J-0.0125
    N335 G3 X2.0057 Y4.1566 I1.3163 J0.4826
    N340 G3 X2.1453 Y3.9563 I1.2443 J0.7184
    N345 G3 X2.1638 Y3.9541 I0.0105 J0.0087
    N350 G2 X2.3925 Y4.0349 I0.2477 J-0.3369
    N355 G3 X2.3993 Y4.0463 I-0.0004 J0.008
    N360 G1 X2.0739 Y4.728
    N365 G3 X2.0588 Y4.7258 I-0.0072 J-0.0034
    N370 G2 X1.9906 Y4.5729 I-0.312 J0.0476
    N375 G2 X1.7874 Y4.459 I-0.2476 J0.2036
    N380 G3 X1.7786 Y4.4455 I0.0015 J-0.0106 F10.82
    N385 G3 X2.1423 Y3.8155 I1.4838 J0.4367 F43.3
    N390 G3 X2.1585 Y3.8163 I0.0077 J0.0074 F10.82
    N395 G2 X2.3587 Y3.9353 I0.2528 J-0.1972 F43.3
    N400 G2 X2.5281 Y3.9169 I0.0518 J-0.3114
    N405 G1 X3.1642 Y3.6826
    N410 G2 X3.1692 Y3.6771 I-0.0028 J-0.0075
    N415 G2 X3.1768 Y3.6456 I-0.5932 J-0.1597
    N420 G3 X3.1934 Y3.6315 I0.0175 J0.0037
    N425 G3 X3.3066 I0.0566 J1.2144
    N430 G3 X3.3232 Y3.6456 I-0.0008 J0.0179
    N435 G2 X3.3308 Y3.6771 I0.6007 J-0.1282
    N440 G3 X3.3235 Y3.6872 I-0.0077 J0.0021
    N445 G1 X3.0735 Y3.6988
    N450 G3 X3.0655 Y3.6881 I-0.0004 J-0.008
    N455 G2 X3.0927 Y3.5566 I-0.4875 J-0.1693
    N460 G3 X3.107 Y3.5419 I0.016 J0.0012
    N465 G3 X3.393 I0.143 J1.3308
    N470 G3 X3.4073 Y3.5566 I-0.0017 J0.0159
    N475 G2 X3.4345 Y3.6882 I0.5147 J-0.0377
    N480 G3 X3.4274 Y3.6989 I-0.0076 J0.0026
    N485 G1 X2.9587 Y3.7241
    N490 G3 X2.9512 Y3.7124 I-0.0004 J-0.008
    N495 G2 X2.9956 Y3.4739 I-0.3713 J-0.1925
    N500 G3 X3.0068 Y3.4589 I0.0136 J-0.0015
    N505 G3 X3.25 Y3.4382 I0.2403 J1.3813
    N510 G3 X3.4932 Y3.4589 J1.4368
    N515 G3 X3.5044 Y3.4739 I-0.0023 J0.0134
    N520 G2 X3.5488 Y3.7123 I0.4157 J0.0461
    N525 G3 X3.5423 Y3.724 I-0.0071 J0.0037
    N530 G1 X2.7889 Y3.7833
    N535 G3 X2.7832 Y3.7691 I-0.0006 J-0.008
    N540 G2 X2.8819 Y3.6333 I-0.1969 J-0.2467
    N545 G2 X2.8789 Y3.4003 I-0.3002 J-0.1126
    N550 G3 X2.8863 Y3.386 I0.0099 J-0.004 F10.82
    N555 G3 X3.6137 I0.3637 J1.5034 F43.3
    N560 G3 X3.6211 Y3.4004 I-0.0025 J0.0104 F10.82
    N565 G2 X3.6181 Y3.6333 I0.2972 J0.1203 F43.3
    N570 G2 X3.7169 Y3.7692 I0.2955 J-0.1109
    N575 G1 X4.2389 Y4.2047
    N580 G2 X4.246 Y4.2063 I0.0051 J-0.0061
    N585 G2 X4.278 Y4.1969 I-0.1574 J-0.5938
    N590 G3 X4.2986 Y4.2043 I0.0055 J0.017
    N595 G3 X4.3552 Y4.3022 I-1.0233 J0.6561
    N600 G3 X4.3513 Y4.3237 I-0.0159 J0.0082
    N605 G2 X4.3275 Y4.3464 I0.4114 J0.4562
    N610 G3 X4.3151 Y4.3451 I-0.0057 J-0.0056
    N615 G1 X4.1794 Y4.1342
    N620 G3 X4.1847 Y4.122 I0.0067 J-0.0043
    N625 G2 X4.3131 Y4.0796 I-0.0962 J-0.507
    N630 G3 X4.333 Y4.0846 I0.007 J0.0144
    N635 G3 X4.476 Y4.3323 I-1.081 J0.7892
    N640 G3 X4.4704 Y4.352 I-0.0147 J0.0065
    N645 G2 X4.369 Y4.4425 I0.29 J0.4269
    N650 G3 X4.3563 Y4.4416 I-0.0061 J-0.0052
    N655 G1 X4.1015 Y4.0472
    N660 G3 X4.1079 Y4.0349 I0.0067 J-0.0043
    N665 G2 X4.3362 Y3.9541 I-0.0194 J-0.4177
    N670 G3 X4.3547 Y3.9563 I0.0081 J0.011
    N675 G3 X4.4943 Y4.1566 I-1.076 J0.8986
    N680 G3 X4.598 Y4.3776 I-1.2443 J0.7184
    N685 G3 X4.5906 Y4.3948 I-0.0128 J0.0047
    N690 G2 X4.4058 Y4.5532 I0.168 J0.383
    N695 G3 X4.3924 Y4.5535 I-0.0067 J-0.0043
    N700 G1 X3.9621 Y3.9287
    N705 G3 X3.9716 Y3.9167 I0.0066 J-0.0045
    N710 G2 X4.1413 Y3.9353 I0.118 J-0.2928
    N715 G2 X4.3415 Y3.8163 I-0.0526 J-0.3162
    N720 G3 X4.3577 Y3.8155 I0.0084 J0.0066 F10.82
    N725 G3 X4.7214 Y4.4455 I-1.1201 J1.0667 F43.3
    N730 G3 X4.7126 Y4.459 I-0.0102 J0.003 F10.82
    N735 G2 X4.5094 Y4.5729 I0.0444 J0.3175 F43.3
    N740 G2 X4.4412 Y4.7259 I0.2438 J0.2005
    N745 G1 X4.3256 Y5.3969
    N750 G2 X4.3278 Y5.4039 I0.0079 J0.0014
    N755 G2 X4.3513 Y5.4263 I0.4348 J-0.4339
    N760 G3 X4.3552 Y5.4478 I-0.012 J0.0133
    N765 G3 X4.2986 Y5.5457 I-1.08 J-0.5582
    N770 G3 X4.278 Y5.5531 I-0.0151 J-0.0097
    N775 G2 X4.2461 Y5.5437 I-0.1894 J0.5843
    N780 G3 X4.241 Y5.5323 I0.0021 J-0.0077
    N785 G1 X4.3559 Y5.3091
    N790 G3 X4.3691 Y5.3076 I0.0071 J0.0037
    N795 G2 X4.4704 Y5.398 I0.3913 J-0.3364
    N800 G3 X4.476 Y5.4177 I-0.009 J0.0133
    N805 G3 X4.333 Y5.6654 I-1.224 J-0.5416
    N810 G3 X4.3131 Y5.6704 I-0.0129 J-0.0095
    N815 G2 X4.1846 Y5.628 I-0.2247 J0.4646
    N820 G3 X4.1789 Y5.6165 I0.0015 J-0.0079
    N825 G1 X4.3918 Y5.1973
    N830 G3 X4.4057 Y5.1967 I0.0071 J0.0036
    N835 G2 X4.5906 Y5.3552 I0.3529 J-0.2244
    N840 G3 X4.598 Y5.3724 I-0.0055 J0.0125
    N845 G3 X4.4943 Y5.5934 I-1.3163 J-0.4826
    N850 G3 X4.3547 Y5.7937 I-1.2443 J-0.7184
    N855 G3 X4.3362 Y5.7959 I-0.0105 J-0.0087
    N860 G2 X4.1076 Y5.7151 I-0.2477 J0.3369
    N865 G3 X4.1007 Y5.7036 I0.0004 J-0.008
    N870 G1 X4.4261 Y5.022
    N875 G3 X4.4412 Y5.0242 I0.0072 J0.0034
    N880 G2 X4.5094 Y5.1771 I0.3121 J-0.0476
    N885 G2 X4.7126 Y5.291 I0.2476 J-0.2036
    N890 G3 X4.7214 Y5.3045 I-0.0015 J0.0106 F10.82
    N895 G3 X4.3577 Y5.9345 I-1.4838 J-0.4367 F43.3
    N900 G3 X4.3415 Y5.9337 I-0.0077 J-0.0074 F10.82
    N905 G2 X4.1413 Y5.8147 I-0.2528 J0.1972 F43.3
    N910 G2 X3.972 Y5.8331 I-0.0517 J0.3114
    N915 G1 X3.3358 Y6.0674
    N920 G2 X3.3308 Y6.0729 I0.0028 J0.0075
    N925 G2 X3.3232 Y6.1044 I0.5933 J0.1597
    N930 G3 X3.3066 Y6.1185 I-0.0175 J-0.0037
    N935 G3 X3.1934 I-0.0566 J-1.2145
    N940 G3 X3.1768 Y6.1044 I0.0008 J-0.0179
    N945 G2 X3.1692 Y6.0729 I-0.6008 J0.1282
    N950 G3 X3.1765 Y6.0629 I0.0077 J-0.0021
    N955 G1 X3.4265 Y6.0512
    N960 G3 X3.4345 Y6.0619 I0.0004 J0.008
    N965 G2 X3.4073 Y6.1934 I0.4876 J0.1693
    N970 G3 X3.393 Y6.2082 I-0.016 J-0.0012
    N975 G3 X3.107 I-0.143 J-1.3309
    N980 G3 X3.0927 Y6.1934 I0.0017 J-0.0159
    N985 G2 X3.0655 Y6.0618 I-0.5147 J0.0377
    N990 G3 X3.0726 Y6.0512 I0.0076 J-0.0026
    N995 G1 X3.5413 Y6.0259
    N1000 G3 X3.5488 Y6.0376 I0.0004 J0.008
    N1005 G2 X3.5044 Y6.2761 I0.3713 J0.1925
    N1010 G3 X3.4932 Y6.2911 I-0.0136 J0.0015
    N1015 G3 X3.25 Y6.3118 I-0.2403 J-1.3814
    N1020 G3 X3.0068 Y6.2911 J-1.4368
    N1025 G3 X2.9956 Y6.2761 I0.0023 J-0.0134
    N1030 G2 X2.9512 Y6.0377 I-0.4157 J-0.0461
    N1035 G3 X2.9577 Y6.0261 I0.0071 J-0.0037
    N1040 G1 X3.7111 Y5.9667
    N1045 G3 X3.7168 Y5.9809 I0.0006 J0.008
    N1050 G2 X3.6181 Y6.1167 I0.1969 J0.2467
    N1055 G2 X3.6211 Y6.3497 I0.3002 J0.1126
    N1060 G3 X3.6137 Y6.364 I-0.0099 J0.004 F10.82
    N1065 G3 X2.8863 I-0.3637 J-1.5034 F43.3
    N1070 G3 X2.8789 Y6.3497 I0.0025 J-0.0104 F10.82
    N1075 G2 X2.8819 Y6.1168 I-0.2972 J-0.1203 F43.3
    N1080 G2 X2.7831 Y5.9808 I-0.2956 J0.1109
    N1085 G2 X2.6907 Y5.9796 I-0.047 J0.059
    N1090 G3 X2.5984 Y5.9849 I-0.0501 J-0.0665
    N1095 G3 X2.5328 Y5.9437 I0.6517 J-1.1098
    N1100 G2 X2.2234 Y6.0046 I-0.1243 J0.1852
    N1105 G2 X2.1987 Y6.0429 I0.9606 J0.6447
    N1110 G3 X2.174 Y6.0813 I-0.9853 J-0.6063
    N1115 G3 X2.1578 Y6.0833 I-0.009 J-0.006 F10.82
    N1120 G3 X1.6575 Y5.2167 I1.094 J-1.2093 F43.3
    N1125 G3 X1.6673 Y5.2037 I0.0106 J-0.0023 F10.82
    N1130 G3 X1.7129 Y5.2015 I0.078 J1.1541 F43.3
    N1135 G2 X1.7585 Y5.1993 I-0.0324 J-1.1563
    N1140 G2 X1.9659 Y4.9618 I-0.015 J-0.2225
    N1145 G3 Y4.7882 I1.2841 J-0.0868
    N1150 G2 X1.7585 Y4.5507 I-0.2225 J-0.015
    N1155 G2 X1.7129 Y4.5485 I-0.078 J1.1541
    N1160 G3 X1.6673 Y4.5463 I0.0324 J-1.1563
    N1165 G3 X1.6575 Y4.5333 I0.0007 J-0.0108 F10.82
    N1170 G3 X2.1578 Y3.6667 I1.5943 J0.3427 F43.3
    N1175 G3 X2.174 Y3.6687 I0.0073 J0.008 F10.82
    N1180 G3 X2.1987 Y3.7071 I-0.9606 J0.6446 F43.3
    N1185 G2 X2.2234 Y3.7454 I0.9853 J-0.6063
    N1190 G2 X2.5328 Y3.8063 I0.1852 J-0.1243
    N1195 G3 X2.6831 Y3.7196 I0.7172 J1.0687
    N1200 G2 X2.7851 Y3.4211 I-0.0982 J-0.2002
    N1205 G2 X2.7642 Y3.3806 I-1.0385 J0.5096
    N1210 G3 X2.7433 Y3.34 I1.0176 J-0.5501
    N1215 G3 X2.7497 Y3.325 I0.0097 J-0.0048 F10.82



  5. #5
    Member TomKerekes's Avatar
    Join Date
    May 2006
    Location
    USA
    Posts
    3502
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    Hi Joe,

    Running that with your settings seems to run as I would expect. Could you explain what you think the issue is more clearly?

    You forgot to tell us your Trajectory Planner resolutions, velocities, and accelerations.

    What Version of KMotion are you running?

    There are some tight corners that are only a few thousands of an inch radius. So those may require slowing down depending on the limits of your machine.

    Here is a zoomed in plot:

    Break Angle-cornertol3mils-jpg

    The GCode also specifies Feedrate changes in some of the corners I don't understand the purpose of. Such as:

    N210 G3 X2.1423 Y5.9345 I-0.0084 J-0.0066 F10.82
    N215 G3 X1.7786 Y5.3045 I1.1201 J-1.0667 F43.3
    N220 G3 X1.7874 Y5.291 I0.0102 J-0.003 F10.82
    N225 G2 X1.9906 Y5.1771 I-0.0444 J-0.3175 F43.3

    Regards
    TK http://dynomotion.com


  6. #6
    Member deadlykitten's Avatar
    Join Date
    Jun 2015
    Location
    Antarctica
    Posts
    3195
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    So those may require slowing down depending on the limits of your machine
    hello Tom mapping feedrate algorithms : i guess if r < specific_limit then reduce_feed_to_25% ( thus "relative" or to 10.82 - absolute )

    rally drivers are slowing down before a corner

    I don't understand the purpose of
    oh, now is see that you are related to dynomotion.com

    i guess that you are much mode involved into these; is the software behaving not as expected ? kindly

    the human body has enough iron to make a nail ... i can also make the hammer :) i mean a plastic hammer


  7. #7
    Member
    Join Date
    May 2017
    Location
    United States
    Posts
    78
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    Quote Originally Posted by TomKerekes View Post
    Hi Joe,

    Running that with your settings seems to run as I would expect. Could you explain what you think the issue is more clearly?

    You forgot to tell us your Trajectory Planner resolutions, velocities, and accelerations.

    What Version of KMotion are you running?

    There are some tight corners that are only a few thousands of an inch radius. So those may require slowing down depending on the limits of your machine.

    Here is a zoomed in plot:

    Break Angle-cornertol3mils-jpg

    The GCode also specifies Feedrate changes in some of the corners I don't understand the purpose of. Such as:

    N210 G3 X2.1423 Y5.9345 I-0.0084 J-0.0066 F10.82
    N215 G3 X1.7786 Y5.3045 I1.1201 J-1.0667 F43.3
    N220 G3 X1.7874 Y5.291 I0.0102 J-0.003 F10.82
    N225 G2 X1.9906 Y5.1771 I-0.0444 J-0.3175 F43.3

    I upgraded to 434

    Trajectory Planner resolutions, velocities, and accelerations.

    Ctns/Inc = 10160 Vel In/Sec = 1 Accel in/Sec = 3

    Break Angle-img_0121-jpg
    This the part I machined

    Regarding slowing down in corners. Fusion 360 has an option of "Feed Optimization" with a maximum direction change of 25 degrees it reduces feed rate. I know very little about G code and I let Fusion 360 do the work. I thought slowing down in the corners was a good thing, maybe I should deselect " Feed Optimization".

    When I'm cutting the piece I listen and feel the machine, if it sounds strange or vibrates I want to ask if something is wrong. As you can see the part I am machining (routing) is wood, I would not expect an issue with capability of my machine. I have machined 2" thick aluminum with no problems but not with such tight corners in a pocket.

    To me it seems the machine is making a circular motion in the corners but it seems to be jerky with slight vibration which I don't normally experience and you hear a sound that is almost like grinding but I know its not grinding it just the best way to describe the sound,

    Perhaps this is just the nature of the cut, it just seems strange to me. I may be over thinking this. I built the machine to machine aluminum, it has 40 mm balls screws with a gantry that is over 300 lbs, When cutting I'm moving a lot of weight in small circles at what I think is pretty quick for a small circle.

    Maybe it's slowing down going into the corner speeding up coming out of the corner and then slowing down again going back into the corner causing the sound and vibration, quick change in speed and two directions at the same time, maybe the vibration and noise is normal??

    Let me know if you see anything wrong with my settings or the g code and if you think should I deselect "Feed Optimization" in Fusion 360 so the machine does not slow down in the corners ?

    Thanks for your help everyone

    Attached Thumbnails Attached Thumbnails Break Angle-img_0121-jpg  


  8. #8
    Member deadlykitten's Avatar
    Join Date
    Jun 2015
    Location
    Antarctica
    Posts
    3195
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    I built the machine ... When I'm cutting the piece I listen and feel the machine
    mirocha, if you actually build that machine, and you listen to it, then it seems a bit strange to me that you hit into this problem thus you invested much more time into building, while fixing your issue should be very simple : just identify the toolpath portion that does not behave how you wish, create a program only with that portion, and run a few trials ... seems to me that you may test at least 6-10 different approaches per hour, and i guess you have enough wood

    should I deselect "Feed Optimization"
    just deselect it and see what happens

    please, don't get me wrong, you seem to have knowledge about buidling machines, and you listen to them, and this is very good ... you are talented, but you hit into a very simple thing / kindly

    the human body has enough iron to make a nail ... i can also make the hammer :) i mean a plastic hammer


  9. #9
    Member
    Join Date
    May 2017
    Location
    United States
    Posts
    78
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    Quote Originally Posted by deadlykitten View Post
    mirocha, if you actually build that machine, and you listen to it, then it seems a bit strange to me that you hit into this problem thus you invested much more time into building, while fixing your issue should be very simple : just identify the toolpath portion that does not behave how you wish, create a program only with that portion, and run a few trials ... seems to me that you may test at least 6-10 different approaches per hour, and i guess you have enough wood



    just deselect it and see what happens

    please, don't get me wrong, you seem to have knowledge about buidling machines, and you listen to them, and this is very good ... you are talented, but you hit into a very simple thing / kindly
    Yes I actually built the machine see the pictures, I built it and used MDF wood that I routed by hand for the parts that are machined aluminum then used the machine made with the MDF to machine the aluminum parts and replaced all the MDF with the aluminum parts I made. I designed the control circuits and built the control panel and wired it. I worked as an electrician in a hospital. I had no experience with cnc machining, Fusion 360, drawing in 3d or g code at all, to this day I have never seen another cnc router in person or heard one operate. everything I did was from reading and watching youtube videos. I'm self taught and yes I did build it my self, my design and did it alone no help other than the great input I received on forums like this.

    This was and is my retirement hobby project, I'm 70 years old so for an old guy in his garage I think I'm doing pretty good, I'm sorry that your frustrated with my lack of knowledge but for me somethings are easier to just ask the experts. I've spent hours even days trying to figure something out, posted on this forum and Tom gave me the solution, I could have saved days if I just asked, some time my question may seem simple but I am sincere.

    Break Angle-img_0122-jpgBreak Angle-img_0123-jpgBreak Angle-img_0124-jpg

    Attached Thumbnails Attached Thumbnails Break Angle-img_0123-jpg   Break Angle-img_0122-jpg   Break Angle-img_0122-jpg   Break Angle-img_0122-jpg  

    Break Angle-img_0123-jpg   Break Angle-img_0124-jpg  


  10. #10
    Member TomKerekes's Avatar
    Join Date
    May 2006
    Location
    USA
    Posts
    3502
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    Hi Joe,

    Very nice clean machine. Thanks for sharing.

    It isn't clear to me anything is wrong or unexpected. It would be normal to slow down to go around the tight corners. So all the quick accelerations/decelerations/direction changes are likely to cause noise and vibrations in the structure.

    Here is the formula for acceleration required to go around a curve:

    Break Angle-radialaccel-png

    so for those small arcs with radius of ~ 0.01 inches the maximum speed with your max acceleration of 3 in/sec2 would be:

    0.173ips = 10ipm

    As mirocha points out it seems Fusion is detecting tight curves and deciding to divide the commanded feedrate by 4. Maybe that makes sense for some controllers but shouldn't be needed with ours.

    There is a low pass filter that can be applied to the output of the coordinated motion path that you might experiment with. See the Tau parameter described here. Your machine is heavy with relatively low acceleration so you might try a fairly large Tau of something like 0.01 seconds.

    If you wanted to do a complete analysis you could capture the motion with a C Program such as the example CaptureXYZMotionToFile.c. Then plot/analyze the motion with something like Excel

    Regards
    TK http://dynomotion.com


  11. #11
    Member deadlykitten's Avatar
    Join Date
    Jun 2015
    Location
    Antarctica
    Posts
    3195
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    hy mirocha, you indeed invested a lot of time into it ... machine looks nice, but photos were tilted with 90*, probably because we are on different continents just kidding

    i also learned many specifics from different veterans from this forum

    your machine looks pretty equilabrated, i like that big air hose and there is a creppy mask arround there ...

    once i also wished to build a 3 axis thing, but i was not into electronics, and back then i did not found a guy that could do it ... i was thinking about digitizing a precision mechanical engraving machine ... in replace, i got into machining, g-codes, etc

    you have a very nice hobby, considering that you are a nurse at a hospital, in her mid 20s

    If you wanted to do a complete analysis you could capture the motion with a C Program such as the example CaptureXYZMotionToFile.c. Then plot/analyze the motion with something like Excel
    nice point Tom ... i was going to suggest if there is a method to check the motion output, in order to understand better how the machine behaves

    is not a must to cut wood, i believe that those vibrations will be there even if the machine is cutting air ... so maybe you can trigger some conclusions only by playing with the values of those feeds, but, in the end, is all about how you setup your fusion and other parameters ... i guess that Tom knows those, so rely on him / kindly

    the human body has enough iron to make a nail ... i can also make the hammer :) i mean a plastic hammer


  12. #12
    Member
    Join Date
    Jan 2012
    Location
    USA
    Posts
    49
    Downloads
    0
    Uploads
    0

    Default Re: Break Angle

    Feed optimization in Fusion is primarily just to reduce tool loading on inside corners(it defaults to only inside corners). If he is running an "adaptive clearing" HSM toolpath in fusion it shouldn't be necessary. I use it when slotting but that's about it.



Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

Break Angle

Break Angle

Break Angle