5 Axis help!

[Gorn@GT]

I need to cut a groove that is .017 wide and 20 degees cocked off the Z plane. 80% of the grove is a radius around zero. I have programmed it using Curve 5-axis. I created a chain on the centerline of the path and another chain offset and above at the 20 degs.

 

The cut looks great in verify but in code its is a bunch of XYZ, BC moves. For the radius part i would like to see an X value B value and Y zero and a big C move to rotate the table. Since it is a .017 endmill all these small move are snaping endmills. Is there a way to control this?

 

Sample code (Current)

N370 X-3.8302 Y-0.7378 Z-2.3403 B38.311 C96.655

N380 X-3.8307 Y-0.7499 Z-2.3382 B38.262 C96.217

N390 X-3.8347 Y-0.7452 Z-2.3359 B38.215 C95.949

N400 X-3.8356 Y-0.7559 Z-2.3337 B38.164 C95.524

N410 X-3.8377 Y-0.7615 Z-2.3314 B38.113 C95.151

N420 X-3.8398 Y-0.7666 Z-2.329 B38.061 C94.782

N430 X-3.8427 Y-0.7689 Z-2.3266 B38.010 C94.442

N440 X-3.8456 Y-0.7707 Z-2.3242 B37.958 C94.106

N450 X-3.85 Y-0.7651 Z-2.3217 B37.907 C93.845

N460 X-3.8529 Y-0.7674 Z-2.3193 B37.855 C93.504

N470 X-3.8565 Y-0.7656 Z-2.3168 B37.803 C93.204

N480 X-3.8589 Y-0.77 Z-2.3144 B37.751 C92.842

N490 X-3.8596 Y-0.7825 Z-2.312 B37.697 C92.399

N500 X-3.8641 Y-0.7764 Z-2.3096 B37.648 C92.144

N510 X-3.867 Y-0.7773 Z-2.3072 B37.598 C91.818

 

 

I am working on X3 my post is by MLC CAD Systems for a DMU70

 

Thanks in advance

[gcode]

You might want to try a 5X swarf toolpath for that one .

Another thing that may help is using the Point

feature to put more moves into the toolpath.

For a .017 dia endmill, a .005 move is nearly

1/3 it's diameter.. I think the smaller the

resolution the better in this case.

[John Summers]

You may be running into the 5-axis 'twilight zone', where the tool axis is nearly parallel to the rotary axis. The rotary axis can rotate unpredictably for a very small xyz move. You might try a lead/lag angle. That would change the relationship between the tool axis and rotary table axis. It could also give you better cutting. It would be easier to figure out if you put your part on the FTP site.

[crazy^millman]

I would look to using axis sub if it will fit for what you are doing. If not then like John said pa close attention you are at A0 C0 or crazy things start to happen.

 

HTH

[Gorn@GT]

I tired swarf cut. I got pretty much the same thing but it would not let me edit the start point. I then found my Geometery was .00002 off Zero in the X. I fixed that. I am still get a ton of moves but many of the moves are .001 degree B and .0001" X & Y moves

 

Sample:

N950 X-4.7621 Y-0.8737 C131.657

N960 Y-0.8738 B29.084 C132.144

N970 Y-0.8739 C132.632

N980 Y-0.8741 C133.120

N990 X-4.762 Y-0.8742 C133.606

N1000 Y-0.8743 B29.083 C134.094

N1010 Y-0.8744 C134.581

N1020 Y-0.8745 C135.069

N1030 Y-0.8746 C135.557

N1040 B29.082 C136.045

N1050 C136.534

 

I am thinking I am going to hand edit it.

[crazy^millman]

Have you tried curve 5 axis. It gives you more control of your vectors.

 

HTH

[Gorn@GT]

I started with 5 axis curve, It allows me to adjust start point. I also compt to a surface which seems to have given me the cleanest code so far.

[wes_mcgee]

Yeah if you are at 20 degrees it doesn't sound like you are in the twilight zone so much. Not sure why the small moves cause the tool breakage, or is it jerky? I agree it seems like you could hand code a rotary move and make it smoother. I don't know of a way to have it be non linearized code, as mastercam always outputs linear code in 5 axis mode?

[MLS]

If you physically build an upper and lower chain with your endpoints aligned EXACTLY where you want the fanning to occur then sync by entity... swarf 5-axis it may work. If there is a .00001 deviation in the points where it fans too and from then it will not. There will be a slight lead or lag vector in that case. The only way to control this type of thing that I know of is with the construction of the original geometry.

 

You should be able to eliminate the B and Z movements, but X and Y will move with C unless the center of whatever arc you are swinging just so happens to be on the center of rotation for the table with that gage length tool and pivot distance for B axis.

 

Also, set your point generator/ tighten your tolerance. You WANT alot of points.