How to profile a loop

[geofox784]

In order to cut glass on my waterjet without shattering it, I have to do loops on each corner without starting new profiles. Lead in / lead out does not work, as the water should not be stopped and started (this will shatter the glass).

I manually draw in these loops at the end. All I need is for RhinoCam to follow the line.


When the shape is joined as one polyline this result is produced:



When the shape is exploded and each line is selected this result is produced:


I guess the main question is: How do I follow a loop? I would be very surprised if this is not possible.

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[beezerlm]

That's a good question. Just tried the same thing on my system and got the same result. The only way I can get it to make the loop is to use engrave but that does not solve your problem. I even tried changing the Z levels of the curves so they technically did not intersect, but I got the same result.

[Melkiades]

U using inside/outside option when profiling.
Here is two ways to resolve this problem:
1. use Engrave instead of profiling. Extend curve at jet radius, it should work
2. use Right/Left option when profiling. It reduce horizontal or vertical size at jet diameter. You can correct it manually by Nudge command in Rhino.
Don't join curve before.

[cnccraft]

The problem occurs because the computer doesn't understand that you want the curve to be single and overlapping. All it sees are 4 curves coming together. All that you need to do is to lower the one edge by anything i.e 0.1mm and then join the loop end again to the lowered curve. (F10 to get the nodes to join them) The loop is now a spiral that curves underneath itself forming a continuous line.

i tested it and it works fine for engraving.

[Jon.N.CNC]

Donek have a excel sheet that cleverly adds arch's to gcode for drag knife. I wonder if it could be adapted for loops.

Pretty sure this could be achieved with hsm tho using "trace" not sure about other cam.

[vmax549]

SheetCam can do it as an automatic function you do NOT have to draw the loops to get it.