DIY Walnut And Steel Table
This walnut and steel conference table build (could also be a dining table) was my most involved woodworking project to date, including drawbored breadboard ends, processing rough lumber, panel glue ups, and more. The build also included a welded steel base using 1″ square tubing.
Get Started with the Metal Table Base
The first step is to break down the steel tubing for the bases. I needed roughly (8) 10 foot lengths of 1” 16 gauge square tubing. The dimensions of the final bases are 76” long, 26” tall, and 18” deep. The bases will have 3” casters installed.
When breaking down steel like this, it’s a great idea to use a technique called gang cutting, where you cut multiple pieces at once. This results in pieces that are exactly the same length.
After cutting the pieces, I gave them a quick grind on the belt grinder to remove any burrs that might get in the way of welding, and then I moved onto welding the bases together.
To assemble the conference table bases, the first section I assembled was the top apron. This top section is made up of two long rails, connected by three shorter rails. These are all simple, 90 degree welds. Weld the four corners then add the center short rail.
Next, weld the legs together. Each leg is held together by a stretcher to keep the legs rigid. This stretcher is roughly 6” from the bottom of the legs. After welding the legs, I went ahead and ground down the welds, since it’s much easier to grind them now while they’re flat on my work table.
After assembling the legs, attach them to either end of the top section of the base. Welding magnets are helpful if you work mostly with 90 degree angles. When the legs are secured, the next step is to add the long center stretcher. This will add lateral stability to the legs. This is welded to the center of the leg stretchers.
The last structural piece on the base is this center support piece. Since the span of the bases are so long, there was a small amount of flex in the bases without this piece. If you are using thicker steel, this won’t be necessary, but I thought it was a good idea to add it to my bases. Attach this piece to the center short rail and the bottom long stretcher.
The final metal pieces to add to the bases are the brackets which will be used to attach the bases to the walnut tops. I made these from 11 gauge angle iron. If I had to do it over again, I would try to find 16 gauge angle iron, since welding the two differing thicknesses of steel was a little tricky.
When drilling the mounting holes in these brackets, I used a bit that was about ⅛” larger than the screws I used to attach the top. You need to add this small amount of wiggle room to account for the wooden tops expanding and contracting seasonally. In total, I welded 7 support brackets on each frame.
With the welding done, I ground down my welds with a flap disc and then prepped the surface for finish by wiping it down with denatured alcohol. Any surface contaminants will affect your paint adhesion, so make sure to be thorough here.
Let’s Move to the Walnut Tops
This was my first project using totally rough cut lumber. I bought this pile of air dried walnut off of Craigslist about two months ago and have had it acclimating to my shop since then. I sorted through the pile and picked about 6 boards to make up my tops.
This walnut is 5/4 thick, a little over an inch, and varies in width from 6 inches up to 10 inches. My jointer has a max capacity of 8”, so, on a few of the pieces, I had to skip plane the boards, joint one edge, and rip off the waste material on the table saw before being able to fit the piece on my jointer. I got lucky and all of the pieces except for one ended up fitting my jointer after cleaning them up a little bit. I did have to rip one of the boards in half to be able to fit it on the jointer, since it was about a foot wide even after cleaning it up!
I ended up dimensioning my boards in two stages. In the first stage, I brought them from rough down to about an 1” thick. I then let them rest for about a week in case they wanted to bow or warp on me, then brought them down to their final dimensions, roughly ¾” thick.
After the boards were to their final dimensions, it was time to join the boards. Just like the bases, I built two separate tops for this conference table. Each top is roughly 22” wide by 84” long with breadboard ends on each top. To join the boards into a panel, I used a Festool Domino XL. This was my first project using the XL and, I must say, the efficiency I’ve gained is pretty incredible.
The first step in the panel assembly is to layout where to cut the mortises for the Dominos. This is also a good opportunity to make sure your boards are gap free. If they aren’t, make sure to pass them over the jointer again. The last thing you want is gaps in your final table top.
If you don’t have a Domino, you can just as easily use a biscuit joiner for the panel glue up. The biscuits or Dominos aren’t really adding any kind of structural strength here, they’re just for alignment. If you’re really brave, you could even forgo any sort of alignment pieces, but this is really risky. When you’re gluing up panels like this, the boards are going to want to slip around along the glue line. Some kind of alignment aid, whether that’s Dominos, biscuits, or dowels, is extremely helpful.
For the glue up, you want to make sure you have plenty of clamps available. Apply glue along the entire joint, making sure your pieces are gap free, and apply clamping force. You want a nice line of glue squeeze out along each joint. Give the glue about 30 minutes to dry and scrape off any squeeze out. It will be much harder to remove once it’s totally dry.
After your panels have finished setting up, trim the ends square. You can use a circular saw with a straight edge or a track saw here. You want to make sure the ends are perfectly square, so take your time laying out your cuts.
Creating the Breadboard Ends
Once the ends of your conference table tops are squared up, it’s time to figure out how you’re going to install your breadboard ends. In my case, I’m once again calling upon the Domino XL. The tool makes quick work of creating the mortises for the breadboards. If you don’t have access to a Domino, there are a bunch of options for installing breadboard ends. You can use a router to create a mortise and tenon joint, you can cut a large sliding dovetail, you can use a tongue and groove joint, and you can even use dowels if you cut some of them loosely to allow for movement.
The whole point of a breadboard end is to allow the top to expand and contract during the changing of the seasons while keeping the ends of the top flush. The tops will mostly move horizontally, along their width, not along of the length of the top. To account for this movement, breadboard ends need to have some sort of path for this movement to occur. When you see people installing breadboard ends using pocket holes, this is a recipe for disaster. The top won’t have room to move and this can end up leading to cracking.
The Domino makes this easy, as it has two setting when cutting the mortises: tight and loose. For breadboard ends, you cut tight mortises into the top and then cut a combination of tight and loose mortises into the breadboards. For a great explanation of this, check out Brian McCauley’s video on using a Domino to install breadboard ends. I’ll have a link to this in the video description.
With the mortises cut into your top, glue in the tenons. Once you’ve installed the tenons on the top, transfer these lines to the breadboards and cut your mortises into the breadboards.
I decided to drawbore my conference table’s breadboard ends onto the tops. This process uses dowels to pull the breadboard ends tight to the top. You accomplish this by drilling holes in the breadboards and then drilling holes in the tenons. When you drill the holes in the tenons, you drill the hole about 1/16” closer to the top. One note on drawboring breadboard ends: you also want to widen your holes in your tenons to allow for movement. You can see me rocking the drill back and forth to widen the holes.
When you pound in the dowel, this misalignment will pull the breadboard towards the top. To help guide the dowels in the holes, I slightly sharpened the ends of my dowels to help them go into the offset holes.
Another trick to help with this is to use a drawbore pin, which is a tapered steel shaft that helps to clear the holes before installing the wooden dowels.
When installing the breadboard ends, you only want to add glue to the center Domino or center of your tenon. The movement of the top will occur around this center section, allowing the rest of the top to expand and contract. You should not apply glue to any of the other tenons going into the breadboards.
To install the dowels, pound them in until about 1/2” protrudes above the surface, and then apply a small amount of glue. This glue should not make it to the tenon, you just want the glue to hold the dowel in place so can’t be pushed through the top accidentally. Once the dowels are pounded home, trim them flush using a flush cut saw.
With the breadboards installed, you can trim them flush. I leave my breadboards slightly long to allow for any misalignment that might happen during installation. I trimmed mine flush using a track saw and table saw.
Applying the Finish to the Walnut Top
With the conference table tops at their final size, it’s time to prep for finish. I filled any knot holes or other surface imperfections with Timbermate, a water based wood filler. After filling any holes, I sanded the top with 80 grit sandpaper and then chamfered the edges of the top and bottom using a router and chamfer bit. I also slightly rounded the corners with a file.
I continued working my way through the grits, going to 120 then finishing with 180. Once I was finished sanding, I wiped the tops down with mineral spirits since I am using an oil-based finish.
For the conference table top finish, I’m using General Finishes Seal-A-Cell for my first coat then following that up with three coats of General Finishes Arm-R-Seal. There are some differing opinions online about whether Seal-A-Cell is really necessary, but General Finishes claims it can help to bring out the grain on highly figured wood, and I’d say that I agree. The grain on the finished tops is absolutely incredible.
You do not sand after applying the Seal-A-Cell and move directly into applying the first coat of Arm-R-Seal. After applying the Arm-R-Seal, I sanded with 320 grit sandpaper. A good way to know whether the finish is ready for sanding is whether it becomes chalky like this. That means it has dried enough to re-coat. After sanding, wipe down with mineral spirits again and apply another coat. Repeat this process as many times as you want till you get the results you’re after. Three coats left me with a really nice finish.
The last part of this build was figuring out how to attach the casters to the steel tubing. There are plastic threaded adapters available for this, but the ones I found were surprisingly expensive, around $8 each. I figured I could make them myself out of scraps instead.
To do this, I measured the inside and outside dimensions of the tubing and cut some rectangular blocks slightly larger than the outside dimensions. Once these blocks were cut, I cut a small amount from each side at the bandsaw, so that they fit inside the steel tubing. I picked up this little trick from Laura Kampf’s steel dining table build and it worked out perfectly. Once I cut the plug, I drilled a hole in the bottom to fit the caster’s stem, and then epoxied the plugs into the bottom of the legs and glued the casters into the plugs.
Last, I attached the bases to the tops using ¾” machine head screws and then added two latches, one at each end of the table, to keep the two halves together. With that, the conference table is finally done!
-The Video and Blog Post was Created by Johnny Brooke of Crafted Workshop in partnership with Acme Tools. Check out more of Johnny’s work at Crafted Workshop.