Undercut in Vcarve

Hello, I am new to CNCs and have looked everywhere I can for the answer to making an undercut that is NOT a keyhole. I have been messing around with the Vcarve trial without a machine and learning the software.
Question: How can I create a custom vector path that would create an overhang on the inside of a bowl like in the picture attached without it coming back up and breaking the lip off?
Thank you for your time.

that would be a great question for the vetrics forum.

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Thank you, Ive been there and currently waiting for the confirmation to be registered. its this one right?

https://forum.vectric.com/

I think I would try to just do a outline and set the top of the bit to just below the point you want under cut and after one pass move x,y to new zero and do as many time as you want the under cut.. should be easy to do.

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I’d first create a closed contour circle path on top of area you want the undercut, and then cut the contour leaving a tiny gap of .001" or less, making it open contour, and then connecting an entry and exit lines from the ends into the center of the bowl away from the edges. Then, simply apply the toolpath. Entry plunge and ending lift will stay out of edges.

Maybe there’s much easier ways, but I believe that should work.

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It could be done with a lead in and a lead out after the initial pocket is carved. V-Carve does not support undercuts, so you would be fooling the software a bit to do it.

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Does vcarve have the concept of an offset like Fusion? You can use the lead in/out to enter/exit the material from the “side” and the offset would cut lateral up to the shaft providing the undercut.

-Tom

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You would either create drive geometry so that your tool will start out far enough out and exit far enough out. The easiest way is to do lead in and lead out on your contouring toolpath.

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I don’t know about in vcarve, I am sure you can fool it to do what you want, but this is super simple in mastercam.

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That can be done in V-Carve by using lead in and lead out features of your toolpath.

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I’ve always found cuts like this are best done by turning compensation off so the center of the cutter follows the path exactly. Then drawings a sketch that defines where the center of the cuter will travel through the entire cut.
You seem to get the most control over the tools movements this way.

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