Odd behaviour creating toolpath

[HJ Seef]

Having some trouble creating an Outside Toolpath.

[CVH]

Concerns Polyline with handle 0x5604 and CAMTOOLPATH$$PwmLaserOffsetMM$$Profile 12
Like Profile 11 an 0.04 offset.

Wouldn't know why and where the CAM offset failed between (26.74,94.16) and (10.00,117.17)

I can only add that Offset OQ works fine for both sides for a fairly simple Polyline with 86 vertices.
There are only 8 larger bulging segments in the contour, each 1x tangent to a line segment.
And that is where issues may be expected.
This GUI method is based on RPolygonOffset what is a Pro resource.

About certain that the CAM offset works segment based.
The CAM methods and resources are also proprietary.

Once assumed/hoped that the CAM offset was more reliable than OQ.
(Related topic or the example file in the Pocketing topic)


The reason for replying is different.
May I ask what the meaning is for offsetting the edge of your copper at both sides?

Knowing that your spot or tool is about 0.1 in diameter, you will end up with a 0.18 wide 'groove'.
And that centered on the edge of the intended pocket.
So, from +0.09 outside to -0.09 inside.

I was convinced that layer 'B_CU' was the edge of the copper to remain.
Also the edge of what to remove.

If not, then please provide a file with the real edges of copper that must remain for a DrawZigzagPocketPath test.

Regards,
CVH

[HJ Seef]

Layer B_CU is the copperlayer for a Printed Circuit Board. Only the cammed lines are being removed in an etching procedure. A distance of 0,08 mm between the copper tracks is far to small. Like a transformer it wil induce voltages in its surrounding tracks. A capacitor is build as two large copper plates isolated by a small distance. If the distance between the tracks is too small and the length too long, it wil serve as an unwanted capacitor, and this introduces delays in signal behaviour.

The cammed outline of the track that behaves strange, is the so called Shielded Earth Ground Plane, and is required to avoid Electro Magnetical Currents en Radio Frequency Interferences.


In 250715_Triac_Module_B_Cu_LaserZigZag.dxf I did use the LaserGRBL post-processor, and creating the Inside and OutSide toolpaths was not a problem. Even using alias tools to widen the distance btetween the tracks was not a problem.


I am getting older and forgot that my laser cutter uses the PWM Laser post-processor. So, I have to redo the same job over again. Using the very same B_Cu file, I now encounter a very odd and curious behaviour when creating the outside toolpath at a distance of 0,04 mm.

More odd, when using an alias tool on that same outline, that toolpath is created without problems.

Therefore, I suspect there is a toolpath-rounding-problem. To test this hypothesis I have changed the T1 tooldiameter from 0,08 to 0,0801 mm. The outside path is now created correctly, BUT now the inside toolpath gets corrupted!

Can it be a divide-rounding-problem? I have changed T1 tot 0,0802 mm. And low and behold; the inside and outside path are now created correctly.

Seems to me like an odd and curious bug in the toolpath-program.


Regards, HJS

[CVH]

Seems to me like an odd and curious bug in the toolpath-program.

Fighting the same battle.

Regards,
CVH