[MikeSibley]

Has anyone cut 45-degree miters on a cnc? I'm making a small box and am trying to figure out how to join the sides, front and back without revealing overlaps and the joint is hidden. Any ideas?

 

[Rebelwork Woodworking]

If the pieces are held down firm enough you should be able too...

 

[ger21]

It's not normally the right tool for the job, but you can.

For best results, I'd use a 90° v bit with a backer board to prevent tearout.
You can also do it with a 3D toolpath, but it'll take forever.

 

[Rebelwork Woodworking]

It's good to get your machine to do as much as possible.

 

[MikeSibley]

I was just curious! Thanks.

 

[bfblack]

If you decide to not use CNC, I would recommend cutting the miters on a table saw using the technique discussed by Steve Latta in the Fine Woodworking article "Strong, No Clamp-Up Corner Joints", March/April 1998. He uses an assembly technique called miter folding which involves using good quality packing tape at the corners. I have successfully used miter folding as well as Latta's simple shop built jig to cut the miters.