Cutting out excess material

Hi all,
Brand new to all things CNC, and of course the Nomad. My first project (beyond the wrench) is to make a box for electronics. We’ve created the 3D file, put it through meshcam, loaded it into Carbide Motion and it actually did everything we wanted it to do…almost. I’m sure it did exactly what we told it to do, but it only cut the interior of the box (grooved lip, screw bosses, etc. ). Looks lovely, but not it’s now sitting in the middle of a larger piece of stock.

Question: Let’s say the box I’m cutting is 1" x 2" x 0.5". My stock is 1.5" x 2.5" x 0.6". How do I tell meshcam and/or Carbide Motion: “when you are done with the inside, please cut around the outside so I have a completely separated box that is 1” x 2" x 0.5"."

Hoping that question makes sense.

Thank you in advance for any pointers!


David, on the Toolpath Paramters screen you’ll need to specify a margin of greater than your cutter’s radius

so the cutter will reach the outside of your part. (MeshCAM always calculates margin, region, keepout areas with the tool axis/centerline as the reference).

And now that you will be cutting the box free of the stock, you’ll probably want to add a couple of supports at the bottom of the geometry (later trimmed by hand) to keep the box from flopping around when the kerf reaches the bottom of the part/stock.

And, if the stock is still in place on the table and you haven’t moved anything, you can just add a Keepout Area (under the CAM | Set Machine Region) to avoid re-machining the inside of the box. Just eyeball the Keepout Area on the box wall.


Did you define “construction tabs” (those red lines that one can specify in MeshCAM)? If you did, those were there to hold the piece still and connected to the stock.

We do not what to have the construction tabs cut while machine is in motion. Cutting them can lead to the part - especially if it’s small - go flying. If it doesn’t go flying, it can vibrate around, damaging the finish and potentially damaging the end mill.

When the job is done, one cuts through the tabs and then routes/grinds/cuts the part sides smooth.