Hey everyone! I'm just diving into woodworking and I'm working on a project to build a box for a piano keyboard. This box is going to serve as a shelf in my desk, so I want the top of the piano to sit almost flush with the desk surface.
The box is designed to hold a weight of 14kg and I'm using 18mm thick plywood for the construction. I'll be box jointing the sides and want to cut a 6mm deep dado in the sides, front, and back to fit the bottom piece. The dimensions of the box are a depth of 320mm and a length of 1432mm. I checked the sagulator, and it seems the sag will be acceptable.
My main question is about the dado cut: how much material should I leave below the dado to make sure it doesn't break?
1 Answer
Typically, a good rule of thumb is to keep the dado depth at no more than half the thickness of the plywood you're working with. Since you're cutting a 6mm deep dado in 18mm plywood, that should be fine! Plywood is pretty strong in that regard, so you shouldn't have any issues with strength.
Thanks for the tip! So, if I cut the dado 10mm above the bottom, that should still be alright?