Results 1 to 11 of 11

01292018, 08:49 AM #1
Bobcad, 4th axis rotary, lots of small angular feeds...
Bobcad V30, 4th axis standard.
Using 4th axis rotary tool paths. Tool feeds to depth on top of part. In a case where the next feed move could be a complete 360 rotation or even maybe only 10 degrees the software breaks the feed into a series of short angular increments. This causes programs to be needlessly long.
Is there a way to force long angular moves where the part design allows it? There may be some way to accomplish this under "Multiaxis Post" settings although I haven't had any luck changing settings there.

TopSolidCAM... liked this post


01302018, 04:58 PM #2
Doug,
It's common for 4 axis + programming that the posted code provides more data points vs less. Having control over the "point density " is even a feature for multiaxis toolpaths. Can you tell me which controller you are running on? Also could you share more details about how you have the rotary toolpath setup?
************
CAM Defaults Multiaxis Posting
It looks like you can use multiaxis posting point interpolation for rapid moves. The max distance option allows you to make the movements smaller, but making them larger seems to be an issue. It may be defaulted in the back round.
Before multi axis changes
(TOOL #1 0.5 0.5000 Dia. 0.2500 CRad. 4 Fl.1.1250 CL)
N03 T1 M06
N04 A0.
N05 G00 G90 G54 X2.25 Y0. S3880 M03
N06 G43 H1 D1 Z2. M08
N07 Z0.6271
N08 Z0.5271
N09 G94 G01 Z0.4271 F44.6296
N10 X0.25 Z0.8271 F89.2592
N11 G00 Z0.9271
N12 Z1.0271
N13 Z2.
N14 X0.375 A2.813
N15 X0.5 A5.625
N16 X0.625 A8.438
N17 X0.75 A11.25
N18 X0.875 A14.063
N19 X1. A16.875
N20 X1.125 A19.688
N21 X1.25 A22.5
N22 X1.375 A25.313
N23 X1.5 A28.125
N24 X1.625 A30.938
N25 X1.75 A33.75
N26 X1.875 A36.563
N27 X2. A39.375
N28 X2.125 A42.188
N29 X2.25 A45.
N30 Z0.6271
N31 Z0.5271
N32 G01 Z0.4271 F44.6296
N33 X0.25 Z0.8271 F89.2592
N34 G00 Z0.9271
N35 Z1.0271
N36 Z2.
N37 X0.375 A47.813
N38 X0.5 A50.625
N39 X0.625 A53.438
N40 X0.75 A56.25
N41 X0.875 A59.063
N42 X1. A61.875
N43 X1.125 A64.688
N44 X1.25 A67.5
N45 X1.375 A70.313
N46 X1.5 A73.125
N47 X1.625 A75.938
N48 X1.75 A78.75
N49 X1.875 A81.563
N50 X2. A84.375
N51 X2.125 A87.188
N52 X2.25 A90.
N53 Z0.6271
N54 Z0.5271
N55 G01 Z0.4271 F44.6296
N56 X0.25 Z0.8271 F89.2592
N57 G00 Z0.9271
N58 Z1.0271
N59 Z2.
N60 X0.375 A92.813
N61 X0.5 A95.625
N62 X0.625 A98.438
N63 X0.75 A101.25
N64 X0.875 A104.063
N65 X1. A106.875
N66 X1.125 A109.688
N67 X1.25 A112.5
N68 X1.375 A115.313
N69 X1.5 A118.125
N70 X1.625 A120.938
N71 X1.75 A123.75
N72 X1.875 A126.563
N73 X2. A129.375
N74 X2.125 A132.188
N75 X2.25 A135.
N76 Z0.6271
N77 Z0.5271
N78 G01 Z0.4271 F44.6296
N79 X0.25 Z0.8271 F89.2592
N80 G00 Z0.9271
N81 Z1.0271
N82 Z2.
N83 X0.375 A137.813
N84 X0.5 A140.625
N85 X0.625 A143.438
N86 X0.75 A146.25
N87 X0.875 A149.063
N88 X1. A151.875
N89 X1.125 A154.688
N90 X1.25 A157.5
N91 X1.375 A160.313
N92 X1.5 A163.125
N93 X1.625 A165.938
N94 X1.75 A168.75
N95 X1.875 A171.563
N96 X2. A174.375
N97 X2.125 A177.188
N98 X2.25 A180.
N99 Z0.6271
N100 Z0.5271
N101 G01 Z0.4271 F44.6296
N102 X0.25 Z0.8271 F89.2592
N103 G00 Z0.9271
N104 Z1.0271
N105 Z2.
N106 X0.375 A182.813
N107 X0.5 A185.625
N108 X0.625 A188.438
N109 X0.75 A191.25
N110 X0.875 A194.063
N111 X1. A196.875
N112 X1.125 A199.688
N113 X1.25 A202.5
N114 X1.375 A205.313
N115 X1.5 A208.125
N116 X1.625 A210.938
N117 X1.75 A213.75
N118 X1.875 A216.563
N119 X2. A219.375
N120 X2.125 A222.188
N121 X2.25 A225.
N122 Z0.6271
N123 Z0.5271
N124 G01 Z0.4271 F44.6296
N125 X0.25 Z0.8271 F89.2592
N126 G00 Z0.9271
N127 Z1.0271
N128 Z2.
N129 X0.375 A227.813
N130 X0.5 A230.625
N131 X0.625 A233.438
N132 X0.75 A236.25
N133 X0.875 A239.063
N134 X1. A241.875
N135 X1.125 A244.688
N136 X1.25 A247.5
N137 X1.375 A250.313
N138 X1.5 A253.125
N139 X1.625 A255.938
N140 X1.75 A258.75
N141 X1.875 A261.563
N142 X2. A264.375
N143 X2.125 A267.188
N144 X2.25 A270.
N145 Z0.6271
N146 Z0.5271
N147 G01 Z0.4271 F44.6296
N148 X0.25 Z0.8271 F89.2592
N149 G00 Z0.9271
N150 Z1.0271
N151 Z2.
N152 X0.375 A272.813
N153 X0.5 A275.625
N154 X0.625 A278.438
N155 X0.75 A281.25
N156 X0.875 A284.063
N157 X1. A286.875
N158 X1.125 A289.688
N159 X1.25 A292.5
N160 X1.375 A295.313
N161 X1.5 A298.125
N162 X1.625 A300.938
N163 X1.75 A303.75
N164 X1.875 A306.563
N165 X2. A309.375
N166 X2.125 A312.188
N167 X2.25 A315.
N168 Z0.6271
N169 Z0.5271
N170 G01 Z0.4271 F44.6296
N171 X0.25 Z0.8271 F89.2592
N172 G00 Z0.9271
N173 Z1.0271
N174 Z2.
N175 M09
N176 M05
N177 G90
N178 T1 M06
(END OF FILE)
N179 M30
(END OF PROGRAM)
%

01302018, 05:45 PM #3
I have found if you use the surface based toolpaths you have control over over the angle step for rapid moves. I think rotary defaults are setup that way for safety reasons.
TOOL #1 0.5 0.5000 Dia. 0.2500 CRad. 4 Fl.1.1250 CL)
N03 T1 M06
N04 A0.
N05 G00 G90 G54 X2.0568 Y0. S3880 M03
N06 G43 H1 D1 Z2. M08
N07 Z1.2661
N08 Z0.8661
N09 G94 G01 Z0.4661 F44.6296
N10 X0.2038 Z0.8367 F89.2592
N11 Z1.2367 F600.
N12 G00 Z1.6367
N13 Z2.
N14 X1.1303 A45.
N15 X2.0568 A90.
N16 Z1.2661
N17 Z0.8661
N18 G01 Z0.4661 F44.6296
N19 X0.2038 Z0.8367 F89.2592
N20 Z1.2367 F600.
N21 G00 Z1.6367
N22 Z2.
N23 X1.1303 A135.
N24 X2.0568 A180.
N25 Z1.2661
N26 Z0.8661
N27 G01 Z0.4661 F44.6296
N28 X0.2038 Z0.8367 F89.2592
N29 Z1.2367 F600.
N30 G00 Z1.6367
N31 Z2.
N32 X1.1303 A225.
N33 X2.0568 A270.
N34 Z1.2661
N35 Z0.8661
N36 G01 Z0.4661 F44.6296
N37 X0.2038 Z0.8367 F89.2592
N38 Z1.2367 F600.
N39 G00 Z1.6367
N40 Z2.
N41 X1.1303 A315.
N42 X2.0568 A360.
N43 Z1.2661
N44 Z0.8661
N45 G01 Z0.4661 F44.6296
N46 X0.2038 Z0.8367 F89.2592
N47 Z1.2367 F600.
N48 G00 Z1.6367
N49 Z2.
N50 X1.1303 A405.
N51 X2.0568 A450.
N52 Z1.2661
N53 Z0.8661
N54 G01 Z0.4661 F44.6296
N55 X0.2038 Z0.8367 F89.2592
N56 Z1.2367 F600.
N57 G00 Z1.6367
N58 Z2.
N59 X1.1303 A495.
N60 X2.0568 A540.
N61 Z1.2661
N62 Z0.8661
N63 G01 Z0.4661 F44.6296
N64 X0.2038 Z0.8367 F89.2592
N65 Z1.2367 F600.
N66 G00 Z1.6367
N67 Z2.
N68 X1.1303 A585.
N69 X2.0568 A630.
N70 Z1.2661
N71 Z0.8661
N72 G01 Z0.4661 F44.6296
N73 X0.2038 Z0.8367 F89.2592
N74 Z1.2367 F600.
N75 G00 Z1.6367
N76 Z2.
N77 M09
N78 M05
N79 G90
N80 T1 M06

01302018, 06:27 PM #4
Thanks Al. I was hoping there was a secret setting to lengthen the rotary feeds, but apparently not so I'll live with it. My machine has unlimited memory anyway.
I grew up with machines with limited memory, the first mill I bought 30 some years ago only had 16K. It's a hard habit to break thinking I have to make my programs as short as possible..

01312018, 09:15 AM #5
I understand, best I can tell it must be defaulted in the background. Like I said I can make smaller moves just not larger moves when using 4 axis standard. If you are a 4 Axis Pro user you'll have more options to adjust this setting. Did you submit a support ticket on this topic?
I also agree with you, it's never a bad thing to have short efficient programs. They make it easier to edit and tell what's going on. With modern CNC's you can throw so much code at them anymore and they just eat it up. Not like those old tape machines...


01312018, 11:47 AM #6
Al, yes, I did submit it to the support folks. No response yet....

01312018, 11:28 PM #7
What about now?

02052018, 06:54 PM #8
Al, I got a response from Bobcad support today.
"... still looking into the post to see if we can make it out put one full move instead of the multiple arc moves. We have a few options to stop it. Just making sure that it works correctly."
If support doesn't come up with a surefire way to do it I may write a program to process the code and condense the series of small moves into single large moves. Sort of a postpost processor.

02052018, 08:38 PM #9
That sounds like a post writer talking about writing a "filter" that could be turned on or off to "condense the small moves to a single large move. This can be accomplised with a post scriptiong block and the advanced posting tab to provie a UI to turn options on and off etc...
** Take Note ***
Condensing those smaller point moves to 1 large move can resulte in clerance problems. The small point locaitons follow a curved motion around the OD of your part. When you turn those points into a line you'll get a "straight" move that could result in the tool cutting right through your part. This is the reson I belive the limites are put into rotary.
With the surface based toolpaths you have more control over the rapid move sizes but you also have leads links and gap control.


02052018, 08:46 PM #10
Link in this flow line toolpath, you can see the link moves are curved. You can also see all the segments of the rapid move as it links from one pass to another.
That curved motion is made into 2 points would be a straight line.
When using rotary toolapths where you are always point toward center line, that stright line move can be trouble.

02062018, 03:29 PM #11
What you show is not the case I was thinking of. My concern was only where there are a series of angular feeds. No feeds in X,Y or Z, just A's.
In the example submitted to support where a full 360 feed could have been done in one line of code (G93 A360 Fnnnn) the system broke the feed into a series of A2.571 feeds.
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