Through Mortise Mailbox With Cnc Work
My old vinyl mailbox was 20 years old and had not weathered well. I've slowly picked away at this project for over a year, with a few revisions to get to the final product. All of the wood work is made out of a 4x4 post. For the stretcher I resawed the 4x4 post down to 2.5" on the bandsaw. This is the first time I've done a resaw which required me to tune up my fathers bandsaw that hadn't been used in 20 years. Then I used a brace and auger bit to hollow out the mortise and then chisels to clean up the hole. I hadn't done much in the way of chisel work and had never used a brace before. I drilled about half way through on one side, then flipped it over and drilled through the other side to minimize tearout.
I then made a simple jig to align the post on a Shark HD4 CNC router. I had used Vcarve to design the 3D file for the router (one of the first projects I designed on the CNC). The jig had to place the post in the same spot 6 times in a row. I first ran the rough cut with a v groove bit and then did the detail work on the fish with a ball nose bit. The machine ran all of the v groove passes first, then I changed the bit and ran all of the ball nose passes.
With the design work completed I sanded to 240 grit and then glued the stretcher into the mortise. Then I used another auger bit to drill out for the dowel pins. This is the first time I've done this as well and it took some practicing to come up with a workflow that didn't lead to a ton of tearout. With the pins in place and pared down flush, I used Spar Urethane to finish the project laying out 6 coats and sanding with 400 grit and set it into concrete.