Wall-Mounted Display Shelf in Bubinga

 Last November my brother Chris asked me if I would be interested in building a wall-mounted display shelf.   The company Chris works for, Standard Motor Products, Inc., had completed construction of a manufacturing plant in Poland and his company was presented a gift by the President of Poland after the plant opened.  The gift was a boxed picture of a country home in Poland, and SMP would like to display the boxed gift in their Corporate Board Room in Long Island where Chris works.  Naturally I said I’d be honored to be involved in such a project so after a few emails between Chris and me we had a plan. 

Design Considerations

As in prior projects I like to first discuss some of the design issues and how we arrived at a final or at least rough-final design.  First the wood:  the board room is predominantly cherry, and the velour box to be displayed is deep red in color.  Initially we just assumed that cherry would be a natural, and it would have been a fine choice.  I’ve done a fair amount of work in Bubinga, which is a very heavy and beautifully colored deep red African hardwood, and I thought that this wood would go well with the cherry décor and add just a little more uniqueness to the display.

The other major issue was that this shelf would be hung from the wall and so we agreed that a French Cleat was appropriate, and offered a nice clean and invisible method of affixing the shelf to the wall.  So after a few iterations on SketchUp, we agreed on a final design as seen in the first two images.

wall-mounted bookshelf 3curved17in-shrp1100

French Cleat Design

 

In the first image you can also see the ends of the dovetails to be used to join the shelf portion of the French cleat to the box.  I can’t think of a stronger way to build this box considering the weight it needs to support, and adds a nice hand-made look to the design.  In the second image you can see the basic design of the French cleat.

Construction Details

With the design complete, it was off to Mount Storm (a local hard-wood wholesaler) to hunt for some nice Bubinga.  (Mount Storm is also a Forest Stewardship Council Certified wholesaler.)  I was quite lucky to find this beautiful piece of 10’ by 13” wide Bubinga.  10' Bubinga slab

 

The value of using such a large piece is that I can build the project from one piece of wood, which really helps keep the color and grain of the wood more consistent throughout the piece.  It also allowed me to use only two pieces of wood for the top and still get the ~24” width I needed.  The grain on this piece would allow for a very nice overall figure on the top section.

 

Middle Section used for TopThe next image shows the 4’ section I cut out of the middle of the board from which I plan to make the top.  I usually make the large flat pieces first in most projects as it gives this joined piece a nice long time to acclimate to the temperature and humidity of the shop before I start any sanding or flattening.

 

The next image is a close up of the wood grain and color after I surface planed it.  This is going to be a very nice piece when it’s done.  Bubinga up Close

The last image shows the two halves of the top in glue-up.  The real artful part of this kind of work happens when you mix and match the cut pieces to actually make the top.  I spent a great deal of time just looking over the whole board before I laid out where to cut and how the pieces would ultimately join together.  The top is butt-joined and also uses biscuits to help strengthen and align the joint.  You can see in this image how the grain of the two boards come together to form an almost book-matched look.  This doesn’t happen by accident, or at least it shouldn’t.

Both Halves of the Top in Glue-up

So that’s where I am so far on our little project.  After this I can start on construction of the box.

Phil

1-29-14

Building the Box

Now that the top is glued and put to the side to acclimate to its surroundings, I can start constructing the shelf upon which the top sits.  The remaining pieces of Bubinga left after making the top are each not wide enough to make either half of the shelf sides.  But if I join them in much the same way I joined the top pieces, I can put together some very nice sides with a very nice grain pattern.

Shelf Sides Laid Out prior to CuttingThe first image shows that by joining the two pieces along the more straight-grained edges of each piece, a nice grain pattern emerges, and is similar to the grain patterns of the top slab.  I could have glued these two pieces together along the edge where the swirlier pattern is, but the grain pattern would have not been very attractive, especially for such a small area as these sides.  I opted for a more matched look between the sides and the top.  I’ve added some green tape to basically show from where each shelf side will come. 

Once the glued panel is set, I can begin the process of cutting the two side pieces.  In the next image I’m cutting one end of the panel square to the side on my cross-cut sled.  Then I’ll cut the panel to length, also using the Squaring up in the Cross-cut Sledcross-cut sled.  Now in the original plan, the top was to be at a 40 degree angle to the vertical, but Chris decided that a 45 degree angle was better in order to minimize glare.  So in the next image you can see the piece being cut into two equal halves at a 45 degree angle using a large miter gauge.  I made a couple of test cuts first on scraps before I cut this final.  In the subsequent image you can see the two halves that match perfectly. 

Cutting the 45 Degree Shelf Half

A Matched Pair

 

 

 

 

 

 

With the two halves cut to size, it was then on to cutting the dovetails in the sides and in the cleat across the back of the shelf.  This cleat will join with the matching wall cleat to hold the shelf against the wall.  In addition to the back shelf cleat, two other boards are needed across the top in order to fasten the top to the shelf component.  For these boards, I used a basic mortise and tenon joint.  In addition to providing a way to join the top to the shelf, these two front pieces also provide additional stability to the overall shelf structure.  Once all the dovetails and mortises and tenons were cut, I then cut the arch at the bottom of the shelf.  You can see all the final individual pieces for the shelf in the following image.

All the Final Pieces for the Shelf

The next image shows the shelf unit with all the pieces dry-fit together.  I also cut the cleat that gets mounted to the wall. You can also see some small slots cut in the front cross pieces which will be used for screwing the top to the shelf.  The slots allow the top panel to expand because the screws will have the room to shift slightly as the top expands and contracts with changes in humidity.Dry Fit Together  In the last image you can see a close-up of the dovetail joint in shelf side.  Now that all the pieces fit nicely together, I can now move on to doing a little more sanding before I glue everything up final.  Then it’s back to the top. Close-up of Dovetails

 

 

 

 

 

 

Phil

2-10-14

 

Finishing and Assembly

After the lower case work was done for the box, I began the sanding process for the three remaining pieces:  the box, the top and the cleat that mounts to the wall.  I sanded all pieces through #400 grit, and cut the top down to its final dimension.  Now that the top is finish sanded and in its final size, I needed to cut a groove along the bottom which will take the retaining strip.  For the strip, I chose a nice piece of Wenge, which has kind of become the new ebony.  It’s a lovely dark brown to black color and finishes well, and will provide a nice contrast to the Bubinga.  This image shows the 3/8” groove in the top where the wenge strip will be attached.wall shelf top with groove

 

The major issue with adding a retaining strip here is that it is a classic cross-grain situation.  In order to compensate for expansion of the top, the retaining strip’s short shallow tenon will not go all the way to the ends of the groove.  In addition, only the middle third of the strip will receive any glue which will allow the outer ends of the top to expand without splitting or popping out the strip.

With the major components essentially done, I wanted to assemble the whole piece to make sure that everything fits as it should, and to actually mount the piece to the wall to make sure it works as designed.  In order to attach the top to the base, I drilled slotted holes through the cross pieces of the base (the ones that are dovetailed to the sides) so that the mounting screws can pivot slightly when the top expands and contracts. You can see the trial mounting in the next image. 

Trial mounting

With all three pieces final sanded I can now begin to apply the finish.  It’s much easier to finish the pieces prior to final assembly and it will allow finish to be applied to all surfaces.  I use two basic finishes for this piece, and both are finishes used by Sam Maloof.  The first finish is comprised of equal parts of semi-gloss varnish, polymerized linseed oil and Tung oil.  The finish is wiped on (flooded) and wiped off after one hour.  This is not a “build” finish, in that it penetrates into the wood as opposed to lying on top and building a layer at a time like polyurethane.  Because this finish is wiped off after each coat, it goes on very thinly, requiring many, many coats.  At one coat/day, finishing can take a while.  This first finish required about a dozen coats to get the look I wanted.  For the next finish, I used a blend of polymerized linseed oil with beeswax melted into it.  This is also a wipe-on/wipe-off finish but required only two coats to yield the luster I wanted.  The combination of this wood, finely sanded, with these finishes is a beautiful combination.  You can see the final product in the last image.

The Finished Product

This was a fun project to build, and as with any project, it had its interesting challenges and surprises.  That is truly the joy of creating something from nothing.

 

Phil Wendt

3/29/14

3 Responses to Wall-Mounted Display Shelf in Bubinga

  1. Chris Wendt says:

    Looks great…I am excited!

    Chris

  2. Chris Wendt says:

    Wonderful!

    I really appreciate this, Phil.

    Chris

  3. Chris Wendt says:

    Excellent! Thank you so much, Phil!

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