CNC cut dining table made from two 2400x1200mm sheets of 18mm plywood. Locks together with no glue and the screwed joints are hidden. It can be easily disassembled and packed flat for relocation.
Step 1: Design
The table has been designed in Solidworks to an original design. I don't have a workshop so it has been designed for finishing and assembly in my lounge with basic tools.
The '+' cutout in the middle is for running power leads up to my laptop.
Step 2: Choose Material and Cut Test Pieces
I've used an 18mm poplar core High Pressure Laminate (HPL) mainly because it was cheap and easy to get hold of. It would be cool to use a better quality birch plywood but poplar was all my budget allowed.
Once you have selected your material it's probably worth making some test pieces to check the fit the critical joints. Make two of these test pieces and then check which fit best. In doing this I found that my plywood was actually closer to 19mm thick. The fit should be a 'free' running fit otherwise you will need to do heaps of additional sanding.
Note: There is enough left over space on the board "P2" to cut the test pieces.
Step 3: Cut Out the Parts
I don't have a CNC router so I've used the services of my local makerspace to get the parts cut out: http://wellingtonmakerspace.com
I just had to pick up the parts which happened to fit nicely in the back of my hatchback.
Step 4: Trim the Tabs
Use a plunge router with a flush trim router bit to clean-up the tabs (little triangles that keep pieces in place on the CNC router)
Step 5: Sanding
Sand all visible edges until smooth. This takes quite a while to do by hand.
Test whether the legs slot together nicely and sand as required. I found some parts were tighter than others and so marked the joins A-A,B-B etc in order to sand and re-test.
Step 6: Coat the Edges
Coat all visible edges with a clear polyurethane or similar. Two coats has given a smooth durable finish.
Step 7: Assemble the Legs
Fit the legs together. They needed some gentle coercion with a soft-face mallet to lock right down.
Step 8: Assemble the Top
Lay the tabletop top face down on a rug or blanket. Put the surrounding parts in place. Carefully flip the legs and place onto the top assembly.
Adjust the pieces until nesting tightly and then tape the surrounding parts in place onto the table top. Carefully lift the legs back off the top assembly.
Step 9: Screw Together Top Assembly
Drill a hole at the base of each of the corner cutouts such that the screw will be hidden under the leg joint. Be careful not to drill right through the top! Drill a countersink on each of the holes and fit countersunk wood screws.
Step 10: Final Assembly
Once again place the upside down legs assembly onto the top assembly. Carefully adjust the pieces to fit using a pen to prop up each of the corners as you align them. Pull the pens out and with the help of a friend flip the newly completed table.