Wednesday, September 7, 2016

Dining Table Experiment – The Base

9:26 PM Comments 1

My Personal Dining Table

A few months ago, I wrote about designing and constructing a new dining table top for our recently remodeled living/dining room. I started by building the top, since we were tired of eating on the couch, but my wife was not to impressed with the strudy, yet utilitarian, melamine boxes we were using as a base. It was off to the drawing board again.

A quick word on the design process. Some people like to have the entire project planned out from start to end. They like minimizing the unknown. I like to begin with more of a framework, and ad lib as I build. As mentioned in the first dining table entry, I forced myself to design within the constraints that the material placed upon me and enjoyed the process of designing the top independently of the base.

In the designing of the base, I started with my wifes one request, which was, “no Parsons-style base!” She wanted a table that you could sit at without hitting or straddling a leg. That pointed me towards a pedestal style base, of which I am not a fan. I have a great distaste for the classic style pedestal table with the central column and four radiating legs, but no worries, this table has more of a modern/industrial look anyway, so lets work within that realm.


My one request for the base was to keep it as unobtrusive as possible. I hate kicking the base of a table while I am seated! I wanted to design a substantial enough base to ensure the table was solid and stable, while keeping its footprint as small as possible.

As you can see in the above design, I started with an assymetric inverted pylon/steel girder kind of look. While I wasn’t hating it, I wasn’t loving it either.


With the next idea, I tried to keep that inverted triangle idea going, but opened up the middle to make it less “heavy”. In this design, only the ends are angled, but I was also looking at angling the sides so the footprint of the base was as small as possible. I was actually really digging this base idea, but my wife wasn’t, so I just kind of sat on the project for a few days, letting ideas bounce around.


The “stewing” of ideas eventually lead to the design you see above, which was the one we ultimately decided to go with. The base is more of a monolithic structure, without the open spaces to give it the lightweight feel. I didn’t want it to feel to brutalist, so I added a graceful curve to each side and added a foot and a cap that would mimic the layered look of the top. I also brought in metal panelling to keep the faces of the base from feeling like a monotonous field of wood grain.


The interior of the base would be a honeycomb of 3/4″ plywood, giving me plenty of substance to glue and screw the wood and metal onto, while keeping the base as lightweight as possible.


I began by cutting and assembling the core of the base, and immediately messed up. The middle of the base is 2″ narrower than the top and bottom of the base. At a cusory glance, my mind interpreted that as a 2″ curve on each side, rather than a 1″ curve on each side. I was going to run with the exagerated curve, but after tweaking the rendering to see the difference, and running through some of the real world ramifications, I decided it would be best to stick with the original design.


Thank goodness all of this will be hidden, because is was a mess of plywood, glue, and brad nails! I cut out a spacer that would build the 2″ curve out to the 1″ curve it should have been from the beginning.


Next, I milled and shaped the four middle legs. The legs were milled from pieces of 8/4 Sapele, and using a template, a shaper, and a pattern bit, I created the 1″ curve into the faces of each piece.


Prior to attaching the middle legs, I skinned the central section of each face with 3/8″ bending plywood that I have been hoarding for years! It felt good to both need it and have it, and to get rid of it from the clutter in the back corner of the shop.┬áThe legs were simply clamped into place until the glue dried.


The corner legs were much the same as the middle legs, except they had two curved faces. Simce I didn’t have any 3″ thick Sapele, I milled up eight faces, cut a mitre into each piece, and glued the pieces together to create a corner leg. I then used the same template to cut the curve into each face of the legs.


As mentioned above, all of the curves were cut using a pattern bit on a small shaper. I much prefer the shaper over a router, since it is so much quieter and stronger. The oversized cutterhead is also much nicer than a smaller router bit, since it cuts smoother and has far less chatter than the 1/2″ shank bits. Eventually, I would like to upgrade to a shaper with a larger table and to a cutterhead with segmented carbide blades.


I installed the corner legs in the exact same way as the middle legs…some glue and clamps and time.


The top and base have two frames each, separated by a middle layer that will have a metal banding detail. I fabricated the wood layers just like a picture frame. Solid wood rails and stiles and mitered corners connected via Dominos.


The base is starting to take shape, with the legs and face skins and inner top and base caps in place.


The top and base are comprised of three layers total, two layers of Sapele sandwiching a middle layer that has a metal banding detail similar to the top. Rather than running the metal band full width along each side, I wanted it to look like the legs continued through the first wood layer, hence the reason for the two wood blocks dividing each side into three sections.


Here is a look at the table base, sans metal paneling or finish. The top and bottom cap not only added a bit more visual appeal by incorporating some design elements from the top, but it also added more stability without adding to much more visual heft.


I attached the metal bands in the exact same way, using the exact same bolts, as on the top. The metal is a 3/4″ wide hot rolled steel flat bar and the bolts are some stainless steel star drive bolts that I picked up for cheap at a garage sale last summer.


I cut all the metal panels and test fitted them prior to any final sanding or finishing of the wooden base.

My decision to use hot rolled flat bar on the top, which I then had to match on the base, was a poor decision. The hot rolled flat bar comes from the steel yard with a black mill scale, which I sanded away with 80 grit sand paper to give it a great patinated look. The problem with doing that is that there was no way I could use hot rolled sheet steel and achieve the same patinated look. It would require ungodly amounts of time and sandpaper to remove that much mill scale from the sheet of steel. So, my only real option was to use a sheet of cold rolled steel and patinate it to look like the hot rolled flat bar. My one saving grace is that the 3/4″ wide flat bar is more of an accent trim and not super visible on the final table.


I work with a local metal fabricator just around the corner from our shop, and they were kind enough to give me some chemicals for patinating steel.

I began the process by sanding the cold rolled steel with a 3×4 vibratory sander and a medium sanding pad. I then donned a pair of rubber gloves and cleaned the surface to remove any grease and oils, since that will prevent the patina from soaking into the metal. With the surface clean and dry, I used a spray bottle to wet a rag, and then with nice even passes, covered the entire area and let dry. The picture above shows what the patina looks like when it is applied to the steel.


Once the patina has dried, I took a scotch brite pad and removed as much of the patina as was necessary to achieve the desired look. Even though the patina began with a bluish-green hue, after scrubbing with the scotch brite pad, the final look gave me the steel gray-black color I was hoping for. The panel on the left is the steel post-patina and the panel on the right is the natural cold rolled steel. Once I sanded away the excess patina to achieve the finished look, the surface was wiped down with Penetrol, an oil based paint additive, to act as a sealer.


Here is a look at the end of the table where you can see the final look of the patinated cold rolled panel and the sanded hot rolled flat bar. The final look is not exactly the same, but is close enough that most people will never see the difference.


Here is a shot looking down the length of the table, which really shows the nice gentle curve of each side.


Since our front room is only 24’x12′ and does triple duty as an entryway, a living room, and a dining room, we needed to push the table up as close to the back wall unit as possible. Therefore, we chose to place a bench on the back side of the table, allowing us to seat 3-4 kids on the back side, one chair on each end, and 3 chairs along the front side. We have everyday seating for 8 people and can easily add an additional chair or stool on each side for a larger dinner party.

Overall, I am very happy with how the table turned out. This was the first time I ever experimented with patinating metal and it is definitely something I will continue to experiment with and incorporate into future projects. We live on the table and use it everyday, and it has held up to the daily abuse very well. It weights a ton, is rock solid, and incredibly stable.

A few items of note: There are smudges on the bottoms of some of the panels, right where dirty socks and feet come in contact. The metal shop that recommended the use of Penetrol also adds a final coating of carnuba wax, which I did not do because I was in a hurry to be done. Maybe if I had applied the wax to the metal surface, the dirt and oil would have a harder time holding onto the surface. One of these days I will clean the panels and apply a coating of carnuba wax to bring it back to its original glory!