Hey All, just got a Shaper Origin and I'm trying to use Sketchup and, well, beyond squares I'm stumped.

I thought an easy thing would be to create dividers for a chisel tray, so a long rectangle with a smooth cutout so you can get your fingers in there. This seems easy but I've got no idea where to start; I made a square but dont know how to change the line....I'd assume that's how you do it? Anyone have any easy advice?

Gracias in advance.