Bentwood Coat Rack

Following an innovative construction method from a classic, this piece will inspire curiosity with its simple, yet dynamic design.

Chair No.14, also known as the café chair, the bistro chair, or “the chair of chairs” by Michael Thonet, is probably one of the most recognizable pieces of furniture in the world. Created in 1859, this bentwood chair has served as the blueprint for modern furniture design.

Known for his innovative steambending techniques, Thonet began experimenting with the process of bending wood to form various chair parts as early as the 1830s. Using a method of soaking thin veneers in hot glue, he would then mold the pliable veneers around a bent form. The results were, lightweight, sturdy, and inexpensive to produce.

Additional revolutionary aspects of Thonet’s designs were the minimal number of parts required for assembly as well as their ability to be disassembled. This allowed for the pieces to be economically shipped “knocked down” and assembled upon delivery to a store or distributor.

It was not long after my introduction to Thonet’s work that I stumbled across an illustrated catalogue from 1904 called Thonet Bentwood & Other Furniture. This visual index explores his extensive breadth of work and provided me with the visual, as well as process-driven inspiration for the piece discussed in this article.

Selecting Right Material

Before you begin, it is important to establish which species of woods (hard vs. soft) are best for steam bending. In my experience, white oak, red oak and ash have all been more than cooperative in their bending yields. Another thing to consider is whether the material you select has been kiln or air-dried. Kiln-dried lumber tends to dry out and harden the lignin, compromising its naturally hygroscopic nature and ultimately affecting its malleability. That said, kiln drying does not render the wood completely useless, but will require an alternative form of preparation before the wood can be adequately bent.

Constructing the Forms

First things first, begin by building a “form” for which your pieces will be bent around while the glue cures. I ended up using some leftover

Baltic birch plywood, although any plywood will do. You will notice that both bending forms are attached to the same backer-board; this was done to consolidate the procedure and is not requisite. With any remaining material, create a series of drying forms that replicate the two constructed for the glue-up. Since the form will be used more than once, a glue-resistant coating is required to prevent the piece from adhering to the form, or worse, damaging it. For this, I chose to cover my plywood with packing tape. Although unattractive in appearance, this application sustains itself over multiple uses.

Prepping Laminations

To create the strips for the bent laminations, resaw the board(s) into several sheets of veneers (about 1/8" in thickness). Once this is complete, move to the planer (or drum sander) and use a backer-board to reduce the thickness of your veneer down to about 3/32". Using the table saw (or band saw), rip your material down into several 3/4"-wide strips. I would implore you to cut a handful of extra just for insurance. With the surplus of strips milled to the desired thickness, it’s time to prep them for bending. Using a bucket, or shop-made trough, soak the strips in warm water for 3-4 hours.

Hot Pipe Bending

In order to achieve the desired radius, I took a hybrid approach to Thonet’s technique of bending wood. Instead of soaking veneers in vats of hot glue, I went with the hot-pipe method of bending to create the sharp radii needed for the laminations. This allowed me to hand-form the individual strips to match the pattern, thus allowing for a less labor-intensive glue up. For this procedure you will need: a steel pipe (about 10" in length and 1-2" in diameter), a propane torch, a vise, and a nod to the pyromaniac within. Side note: when working with an open flame, make sure your area is well ventilated.

Water, Fire, Pipe

With strips adequately saturated, begin by heating the pipe using the propane torch. The key is to get the pipe hot enough to where the water beads off the pipe (around 215° F).

Once you have reached the correct temperature, start moving the strip back and forth over the pipe. This process helps raise the temperature of the wood enough to soften the lignin, thus allowing the wood to “relax” and flex. As the piece moves across the hot pipe, the water will begin to evaporate and dry out the wood. To remedy this, keep a sponge handy and reapply water as needed to prevent scorching. Once you have completed seven pieces, clamp them in succession around a drying form while you proceed with the next group. Complete this process for all upper as well as lower laminations (42 in total) and allow the strips to dry for 24 to 48 hours.

Glue Up and Hook Construction

With the strips dry, it is time to start our bent-lamination glue-ups. With the jig created, it was possible for me to tackle one hook at a time. If you are looking to expedite the process, you can create a gluing form for each of the hook assemblies. Apply glue to both the front, and the back of each strip and clamp them around their respected forms. Once the glue is dry, head over to the band saw and rip the hooks down to just shy of the final 1/2" thickness. Clean up any blade marks by attaching a piece of

adhesive-backed sandpaper onto a flat surface. Proceed to work the lamination across the sandpaper until the piece is smooth.

Using either the band saw, or the table saw, cut all the laminations down to their final lengths. Once this is accomplished, cut the shoulders and cheeks of the bridle joint using the band saw, or a combination of handsaw as well as band saw — dealer’s choice. Head to the drill press and drill the 1/4" dowel holes that accept the ball knobs. Considering the delicate size of the hooks, a minor amount of flex may occur while drilling these holes. Make sure your piece is not only clamped securely to the fence but reinforced on the exterior of the curve of the lamination — even the smallest amount of give will create an off-center hole. Once the holes have been drilled, proceed to glue up the corresponding laminations that complete a hook. For an added line of security, I went ahead and pinned my bridle joint with 1/8" dowel.

With your hook assemblies in hand, move to the drill press and drill two 1/4" holes on the backside of the lower lamination. These holes will receive two corresponding dowels that attach the hooks to the rack mounting plate. Once complete, head over to the router table and create a chamfer on all sides of the hook. Note: chamfer the ends before it reaches the mounting-plate on the backside of the lower hook. This is done to allow for maximum surface area contact, thus ensuring rigidity of the hook. With the hooks complete, it is time to direct our attention towards the rack.

1 Michael Thonet (shown here) stands beside his Chair No. 14. Originally designed in 1859, this iconic form is considered to be the first piece of mass-produced furniture. It consisted of six pieces, 10 screws, and two nuts.

2 The only requirement for a “proper” bucket, is its ability to retain water, that, and be large enough to submerge the veneers for soaking.

Free-form your veneers using the drying form as a guide.

Without a thermometer? No problem. Just splash some water onto the hot pipe. If the water beads off rather than evaporating, you are ready to bend.

Clamp all seven of the veneers around the drying form together. This will aid in the ease of the glue-up that follows.

10 Packaging tape was used to prevent the glue squeeze-out from adhering to the form. It may not look pretty, but it’s effective.

8-9 Apply a thin layer of glue to both sides of each veneer (with the exception of the first and last). This will ensure a solid bond and reduce springback.

6-7 Use cauls to evenly distribute clamping pressure while drying.

11 Square up the sides of the lamination by removing about an 1/8" off each side, using the band saw.

12-13 Here, the band saw was used to cut the two lamination assemblies to their final lengths.

14-15 Create the cheeks of the bridle joint starting with a couple of stop cuts. Clean out the bottom of the joint with an 1/8" bench chisel.

16-17 Here, the band saw was used to create the shoulder cuts for two corresponding laminations; however, a table saw is equally effective.

18 Check the fit of your joint and make any necessary adjustments.

19-20 Use stop blocks to accurately position your laminations for drilling. Moreover, if you experience any “flex” from the downward pressure of the drill bit, place a block under the curve to stabilize the piece.