Build Humidor

While strolling through a local wood show this past summer, I came across the most beautiful piece of wood. You know the old cliché of eyes meeting across a room? Well that's how I met this spectacular piece of spalted maple. From fifty feet away its dark pattern beckoned me over. How much is that? I thought to myself. Usually good spalted maple is quite pricey, but I wandered over anyway. Much to my surprise its masking tape tag sported an unbelievable $10 price. Must be per board foot, I figured. I asked anyway. Nope. Ten dollars for the whole board. Needless to say, the board came home with me.

Now I'm not a big smoker: but have been known to indulge in the occasional cigar. As soon as I had the board in my hands, I knew just what to do with it: buildhumidor boxes. I had seen others build humidor boxes before and had always admired the arresting smell of Spanish cedar and the often gaudy use of exotic materials in their construction. This piece of spalted maple seemed like the perfect exotic Canadian solution.

The structure of a humidor is actually quite simple--build humidor box and line it with Spanish cedar. I started with a board that was 3/4" thick, 91/2" wide and 64" long and spent a great deal of time figuring out the best use ofthe wood to get the largest box. To help lay out the pieces for the box, cut holes in a piece of bristol board the same size as the pieces required. Position this template over the spalted maple blank and move it around to visualize how the pieces will look in the finished box. This allows the best combination of grain and spalting to be determined before any cuts are made.

Once the pieces are laid out, surface dress the rough stock. My initial surfacing attempt with a thickness planer resulted in a poor quality surface--even with freshly-honed blades--most likely because of the spalting. A switch to a sharp smoothing plane was all that was needed to tame the unruly spalting.

With the rough stock dressed, start to build humidor boxes by cutting all the outer box pieces to width and length. Next, cut the metres that form the corners of the outer box. I used an extension block mounted to the mitre gauge on my tablesaw. When the mitres are cut, dry fit the box together. Use big elastic bands--the kind that come with broccoli--to hold them in place. When you are satisfied with the fit cut the grooves that hold the corner splines. Do this using the same setup as the mitres, just move the metre gauge to the other side of the blade. Clamp a stop block to the mitre gauge to keep the spline grooves consistent on all pieces.

I used a scrap of black walnut to build humidor splines. It was a natural choice for two reasons: like the maple, black walnut is a domestic to Canada; and the colour of the walnut echoed the dark spalting in the maple.

Using a tablesaw, cut a rabbet for the outer lid and bottom. The edge inlay will eventually hide this seam. After all the rabbets are cut, dry fit again using more large elastic bands (I hope you eat as much broccoli as I do). Once you are satisfied with the fit, assemble the box again using glue this time. Use polyurethane glue as a safeguard against the high humidity the joints will encounter. Leave the glue to cure overnight and remove any hardened foamy squeeze-out with a sharp chisel.

Inlaying the Edges

Walnut splines and edge inlays contrast beautifully with the dark markings in the spalted maple.

The edges of the outer box get a decorative inlay. Before you balk at the apparent difficulty of inlaying a contrasting wood on theedges of your box be assured that this is nothing more than a strip of wood inserted in a rabbetthat is as deep as it is wide. Cut the rabbets onthe tablesaw and fill them with more black walnut. Start with the top and bottom inlay pieces, mitring the corners as you go. Adhere the walnut strips with PVA glue and clamp in position with masking tape. When the top and bottom edges are done fill in the corner edges. Once the glue is dry use a block plane with a very fine mouth to plane the inlay strips flush.

When the outer humidorbox is finished cut the lid off using a tablesaw. Once the lid is separated from the humidor box, smooth the cut edges with a scraper.

The Cedar Lining

Use polyurethane glue to edge-join the 3"-wide strips of Spanish cedar together to get wide enough blanks for the inner lining. After planing the glued-up blanks smooth, proceed with cutting the lining pieces to size. The entire box lining is pressure-fit except for the last two short pieces. These get a bit of glue along their bottom edges. Pressure fitting the lining allows the sides to move with changes in humidity. Fit the bottom first, then the long sides and finally the short sides. Leave the top edge 1/4" proud to act as the seal with the top of the box. Use a plane to take a bit off the top edge allowing the humidor box to close without restriction.

If you've ever cut and split maple firewood from less-than-vibrant trees, spalting isn't new to you. It's one of the first stages of wood decay, but if the process is arrested early enough the random pattern of dark brown squiggles left by the spalting moulds can be quite striking, and the wood will still be structurally sound. Many woods can develop spalting if exposed to the right conditions during storage, but maple is especially prone to it because it's rich in natural sugars and low in tannins that restrict microbial activity. Although spalted lumber is often the product of accidental neglect, the effect can be created intentionally. Spalting moulds are everywhere and thrive best under conditions ranging from 20% to 28% moisture content and a temperature range of 10°C to 32°C.

To spalt small pieces of maple, soak them in water, place the wood in a tightly-sealed plastic bag, then stash the bundle in a dark place that's about 20°C. Periodically check on the progress of the microbes and dry the lumber when several passes with a sharp hand plane reveals the look you're after.
--Steve Maxwell

Finishing Touches

With the lid placed onto the humidorbox, mark the positions of the hinges. Drill out the pockets required for the quadrant hinges' travel arms and pare to final shape using a sharp chisel.

To dress the humidor box use a smoothing plane set very fine to take off any high spots. Finally, install the humidifying puck and hygrometer which distinguishes the box as a humidor.

Finishto buildhumidor boxes with three coats of rubbed-out polyurethane, sanding with 600-grit wet/dry sandpaper between coats. Follow the poly with a coat of wax over the entire box.

I can't wait until I find my next piece of spalted maple. That will be cause for celebration--maybe even a good cigar!