Intro: CNC'd Bento Boxes Made From Port Orford Cedar
My family eats a lot. We also love to host dinner parties. We go on picnic adventures. For this Instructable I will show how to make beautiful, durable, stacking ovoid cedar boxes to transport any kind of food from the kitchen to the world. Or the dinner table. I chose cedar as a material because of its ability to remain stable when the boxes are washed. The cedar is also aromatic and imparts a subtle, wonderful flavor to the food. Welcome to our sushi party and I will explain how I made these boxes!
Step 1: Safety First!
Woodworking can be dangerous. Take time and make sure that all of your personal safety gear is close at hand and worn when necessary. Respirator, safety glasses and ear protection are a must for a lifetime of enjoyable making.
Step 2: Glue the Base and Lid to a Spoil Board Using a Vacuum Press.
I laminated 1-3/4" and 1/2" cedar to two separate spoil boards using Titebond 2. It is important to glue both sides of the material to be glued. I use a vacuum press which is a very efficient way to clamp, but hand clamps will work as well. Be sure to cover the the work with cardboard so the bag does not get damaged. Clamp overnight for best success.
Step 3: Design the Boxes and Prepare the Robot
I use hand sketching for drawing the box concepts. I wanted to create two stacking boxes with a lid for a one-person meal. Since there are three of us in the family I wanted to make a total of three. The beauty of a CNC'd routed box is the limitless possibilities of shape, size and amount. I use Autodesk Fusion 360 for my CAD/CAM operations. This is a fairly simple profile so any 2D vector program will work as long as the file can be exported as a DXF file and saved as a part file. In this case I am using a ShopBot PRS Alpha with a 1/2" spiral end mill.
Step 4: Route the Base and Lid Shapes
I profile the outside edge to the depth of the spoil board and the inside pocket to leave 1/4" bottom thickness. I then profile the lid with an outside edge profile the depth of the spoil board. (note: lid routing is not shown).
Step 5: Bandsaw Rip to the Spoil Board
To adjust the bandsaw fence for ripping, please see my other Instructable Get The Drift: https://www.instructables.com/id/Get-the-Drift-Tun...
With a sharp blade and tuned bandsaw, the boxes are released from the wood blank.
Step 6: Hand Plane the Lids
I am a sucker for a hand planed surface. With a few passes with a sharp smoothing plane the top becomes a glassy finish. Doing it while it is still in wood blank form allows for ease of clamping.
Step 7: Route the Lid and Base With a Rabbit Joint
When I designed the boxes I knew that I wanted to use the router table for the lid rabbit. I made the wall thickness 1/16" less than the rabbiting bit for a nice fit. I set the depth to 3/32". The bottom of the lid and the base are both rabbited. They should fit nicely at this point.
Step 8: Chamfer the Edges
The chamfer creates a nice material break as well as hiding any imperfections that may occur in the profile after sanding.
Step 9: Sand the Profile
I really dislike hand sanding. Using the pump drum and sanding flaps reduces time and effort. Since these boxes are for utility and will age and patina over time. I sand any tool marks off to 120 grit.
Step 10: Detail Sanding
Spending as little time as possible, knock down all fuzzy edges with 120 grit sandpaper or sanding sponges. Remember, these are not-too-precious boxes, so a fine finish is not necessary.
Step 11: Admire the Boxes and Don't Apply Finish
Maybe have a beer as well. I don't use finish for the boxes. Cedar remains stable when wet so they can be washed regularly. They will age over time to a beautiful patina.
Step 12: Fill With Goodies and Eat!
My favorite part: we made a trip to Tokyo Fish Market in Berkeley for some fine produce. http://www.tokyofish.net/
We had yellowfin, salmon, fish roe, uni, chanterelle mushrooms, octopus, shisho leaves, fresh wasabi, egg, Japanese Pickles, four different kinds of Pumpkin and Squash.
The boxes performed beautifully and the subtle flavor of the Cedar wood was wonderful. The chanterelle mushrooms we gathered earlier in the week mixed with the uni and shisho leaf in an amazing way. Guest brought some amazing mezcal and we were in heaven!