Break at interesection

[jcnewbie]

Another issue I've run into..

Create a circle of any diameter and create a verticle line from the top quadrant all the way pass the bottom quadrant of the cirlce. Now if you go to edit - trim - break at intersection, and select the line and circle, why does the circle split into 3 arcs ? I would expect it to break the arc in only 2.

[beege]

Mastercam circles start and end at three o'clock, unless you make it differently. Cutting a circle in half vertically yields three arcs, one from twelve to three, one from three to six, and one from six to twelve. One would think that circles have no start point, but for some reason they do...

[Andre' B]

Thus the reason I try to do all the CAD stuff in a CAD program before importing into MasterCAM for the CAM stuff.

[jcnewbie]

what about 6 to 9 or (-90 to -180 degrees) ? Where is that arc ? If you have a result of an arc from 6-12 mastercam thus should create an arc from 6 to 9

[beege]

The 6-9 arc doesn't happen. Take a rope, make a circle with the ends at three o'clock. Now take a knife and cut in half vertically, from 12 to six. You'd be left with two short pieces on the right, and a longer piece on the left. Two endpoints exist at three on a mcam circle. cut it vertically and four more endpoints are created, two at twelve and two at six. Nothing has created endpoints at nine. I don't know how else to describe it...

[sti2011]

Originally Posted by jcnewbie what about 6 to 9 or (-90 to -180 degrees) ? Where is that arc ? If you have a result of an arc from 6-12 mastercam thus should create an arc from 6 to 9

If you wanted to generate an arc from 12-6 it should start at 90 and end at 270
If you wanted to generate an arc from 6-12 it should start at 270 and end at 90
3'oclock is an angle of 0 and 360 degrees and all increments are counterclockwise. 12 being 90 9 being 180 6 being 270
Never used a negative value on angles other than a calculated result this may be some of the problem