Circular Interpolation help


I’m new to Shapeoko and Carbide Create but not new to CNC programming and machining.

My first project is to create a waste board and I’m circular interpolating the holes. I use GibbsCam for programming and the post processor I have generates circles with I’s and J’s G2 and G3 and NOT line segments.

When I do a sample circle in Carbide Create I notice it does not generate G2, G3 I’s and J’s but line segments.

Is there a way to use true circular interpolation on the Shapeoko without me having to learn Carbide Create.


You would need to use a CAM tool which generates G2/G3 arcs — the ones from GibbsCAM ought to work — don’t they?

A free graphical CAD/CAM alternativ which generats G2/G3 arcs is MakerCAM, Vectric VCarve can do this as well if enabled in the post-processor.

Yeah Gibbs allows you to create line segments with a tolerance which you can adjust eg: .001 It still does an arc in and out of the cut but I think 90 degrees or less so I will give that a shot

You don’t need to use carbide create to generate code - you can keep using gibbs if you like.

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Grbl will calculate the arcs on the fly and essentially move the machine in tiny segments when you send G2s and G3s. The tolerance is based on your $12 setting.

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