Turning - Make sharp corners

[Anonymous]

The "Make Sharp Corners" function is not working as I think it should. I get a radius added to the start and end points

of all chamfers when post processing. I've played with the (built in) minimum circular tolerance on the post page and

can get the output to not include the radii but then the chamfer is output in many steps. Changing the (built in)

miumum chord length seems to have no effect. Lead in and out are set to no radius.

Any help is appreciated.

[jeff.walters]

A screen shot or better yet the part would help but keep in mind that the 2D chamfer is actually a 3D toolpath so there may well be times its using what looks like an arc and outputs linear moves.

[Anonymous]

Jeff, Thanks for the reply. It is the Gcode output that has arcs in it. G3's in this particular case. If I change the

tool to a sharp point the Gcode output has no arcs but then of course the path is not offset by the tool nose

radius. I may have something set up incorrectly in the software but I don't know for sure. That's why my

question. Or is the Make Sharp Corners function not working properly (bug) ? I can get a screen shot tonight.

BTW I'm just using the generic Fanuc post processor at this time.

Thanks

Allan

[jeff.walters]

True but it could be a setting or the way you’re approaching it that’s causing it.

[Anonymous]

Jeff, here's a screen shot of a test piece. Very simple example with two .03 x 45 deg. chamfers.

I also attached the code. You can see I get arcs at the start and end points of both chamfers.

Thanks

Allan

%
O1234 (FIRST TEST)
G98 G18
G20
G50 S4000
G28 U0.

(PROFILE1)
T0101
G54
M8
G99
G50 S4000
G96 S350 M3
G0 X2.2 Z0.1969
G1 Z0.0796 F9.84252
X1.6095
Z-0.0004 F0.005
Z-0.675
X1.6275
G18 G3 X1.9545 Z-0.7427 R0.2313
G1 X1.9992 Z-0.7651
X2.1592
Z0.0796 F9.84252
X1.2836
X1.2199 F0.005
Z-0.0004
X1.2645 Z-0.0227
G3 X1.4 Z-0.1863 R0.2313
G1 Z-0.675
X1.6275
G3 X1.8095 Z-0.6937 R0.2313
G1 X1.9695
Z0.0035 F9.84252
X-0.0625
Z-0.125
X0.8775 F0.005
G3 X0.9217 Z-0.1342 R0.0312    ARCING INTO CHAMFER
G1 X0.9817 Z-0.1642            CUTS CHAMFER
G3 X1. Z-0.1863 R0.0313        ARCING OUT OF CHAMFER
G1 Z-0.875
X1.6275
G3 X1.6717 Z-0.8842 R0.0312    ARCING INTO CHAMFER
G1 X1.7317 Z-0.9142            CUTS CHAMFER
G3 X1.75 Z-0.9362 R0.0312      ARCING OUT OF CHAMFER
G1 Z-1.9063
X1.91
X2.2 F9.84252
Z0.1969

M9
G28 U0. W0.
M30
%

[jeff.walters]

So if I'm reading you right what you want is to get rid of the corners shown below.

Sorry to say right now we don’t have a control in turning profiles to handle this. The Sharp Corners is for inside corners and have no effect on outside corners. What I suggested to the developers on ticket CAM-3703 is to add in outer corner mode (see below) like we have in mill 2D Contour.

[Anonymous · Accepted solution]

Jeff, Yes that is exactly what I'm asking.  An option to turn it on or off would be great.

Thank you much,

Allan