Confidence is that feeling you get in the design stage. Suggest you get a bit of MDF, stick it in the vice and try bending it, you will find it goes easily one way and hard in the other. Right angle joints are your friends.

You started out designing a machine to cut PCB's and then, with an eye to the future, you enlarged it so you could make saucepans. You now have something that will do neither.

Strongly suggest you scale it back to cut chocolate box sizes. It should look chunky, the only thing on it that should look spindly is the spindle