Introduction: Lots of Tables!

About: The Columbus Idea Foundry is Central Ohio’s premier community workshop, maker space, and learning center. We offer variety of conventional and high tech tools (wood shop, metal smithing and foundry, laser cut…

What was the project?

We were contracted by Fuse (a Columbus-based innovation lab at Cardinal Health, focused on improving the future of health and wellness) to build 10 standing height tables for their new office expansion. At the Columbus Idea Foundry, we regularly teach people how to use our tools so that they can build their own projects. We also receive commission requests from folks who don't have the time to make their own projects. (They'd rather hire us to make them instead, and we're only happy to oblige). This was one such commission. Fuse requested eight 8' X 4' tables, and two 4' X 4' tables. All tables were 42" tall.

They originally wanted butcher block tops, but in the end decided on 1" thick bamboo plywood. We've worked with bamboo plywood many times in the past; once we showed them a couple pictures of what finished bamboo looks like, they were hooked. All of the bases were made from 1.5" square, steel tubing with 1/8" thick walls. They wanted the tables to be sturdy (to hold multiple heavy monitors each without deflecting), and also to look professional and industrial at the same time. The bamboo and raw steel together make a perfect match.

Step 1: The Bamboo Tops

Time Frame: We had 3-4 weeks in which to do this job. This was, of course, with several other projects running simultaneously.

Materials: * Bamboo: 9 sheets of 4' x 8' x 1" thick, 3 ply bamboo plywood from Plyboo. This stuff is pricey, but well worth it. It's gorgeous, sturdy, and easy to work with. Unfortunately, we couldn’t source it locally. Shipping for the bamboo alone was over $300!

* Steel: 20 pcs of 1.5" square, hollow steel tubing with 1/8" thick walls. Each piece was 20' long. These pieces were cut down to the different sizes we needed.

* Steel: 1 pc of 1.5" flat stock at .25" thick. We cut a 10' piece down into a bunch of 1.5" x 1.5" square pieces to weld onto the bottom of each leg so we could attach a leveling foot.

* Leveling feet from Amazon. We cut threads in the bottom of each leg so we could screw these in. * 1" angle brackets for securing the tops to the base. Bought from Lowes.

* Zinsser Bulls-Eye Spray Shellac (clear) from Lowes. This is what we used to seal and protect the steel bases.

* Minwax Fast Drying Polyurethane (semi-gloss), from Lowes. This was used to seal and protect the Bamboo tops.

* Several foam brushes and foam rollers for applying the polyurethane to the tops.

What processes or techniques did we use?


Since most of the tops already came in the size we needed (4' x 8'), there wasn’t too much cutting required. For the 4' x 4' tables, we used our vertical panel saw to cross cut a full sheet in half.

We used our 48"x96" ShopBot CNC router table to cut the 4" holes down the center of each table top. These holes were for wire management purposes. We could have used a jig saw or something similar, but the CNC router table made quick work of it and allowed us to be very precise.

Once off the Shopbot, we used a hand-held trim router to soften every edge. The router bit we used was a 1/4" roundover bit. This gave all the sharp bamboo edges a very soft feel. When the programmers at Fuse are coding away, the edges of the table won't be digging into their forearms.

The final step before polyurethane is sanding. The large slabs of bamboo are gorgeous, but they required quite a bit of sanding to clean up machine marks (marks that were made when they cut the wood at the manufacturer).

The top surfaces of the tables were fairly easy to sand as each sheet of bamboo comes wrapped in plastic. We used a random orbit sander with 180 grit sandpaper to make the tops nice and smooth.

The edges of the tables were another creature entirely. The factory edge (where they cut the sheets down at the manufacturer) were pretty rough. To clean these up, we had to start with a belt sander with 100 grit paper. In the wrong hands, a belt sander can ruin a project in the blink of an eye, but Matt has been using them for years and has a ton of 'fearful respect' for them. Once cleaned up with the belt sander, we switched back to the random orbit sander with 180 grit paper and clean up the marks left by the belt sander.

We cleaned up all of the rounded edges with a fine sanding block (love these!) because they contoured with the edges so well.

After all that sanding, it was time to finish these bad boys with some semi-gloss polyurethane. This was a bigger task than we imagined. Where the heck do you put eight 8 foot by 4 foot table tops, plus the two smaller ones?! We ended up schlepping them upstairs to our 2nd floor and putting them on tables all over the damned place. :-)

We used a really cool technique, "rolling and tipping", to apply the polyurethane to the tops. Rolling and tipping is when you roll on the finish with a small foam roller, and then quickly go over it with a foam brush – just the tip of the brush, very lightly – while it's still wet. Done correctly, this will leave a glass smooth finish with zero brush marks. In our experience, it's the best method for applying finish to a large surface, unless you have a spray booth.

In the end, the tabletops turned out absolutely gorgeous. The polyurethane sealed them from harm and brought out so much of the beautiful bamboo characteristics and colors.

Step 2: Next Up, the Steel Bases!

At the Columbus Idea Foundry, we value experience, and the knowledge gained from doing things. We learn something every time we take on a new project. So we weren't too surprised when the stock for the steel table bases arrived on a large flatbed, but we were a bit surprised that each piece was literally dripping with machine oil. That damned oil slowed us down several times throughout the process.

Each piece of hollow square steel was 20 feet long, which we had to cut down into over 100 separate pieces. Luckily, we have a sexy, monster of a tool – a brand new Eisen 9"x16" horizontal bandsaw. This beast can saw through a structural 'I' beam! It made quick work of the much smaller 1.5" square tubing, although we went through a large container of acetone trying to get all the oil off so we could start welding.

Speaking of welding, next comes the grinding.... That's right,
you grind before you start to weld. Every joint that is going to be welded has to be metallurgically clean steel. Almost all new steel you buy will come with 'mill scale' on it. This is a very hard, thin coating of oxide that appears on all hot rolled steel, and prevents a good weld from being formed.

So we spent several long, hard afternoons in the welding room giving
each weld spot a ¼ inch bevel so the welds would be clean and super secure. (Don't tell anyone, but I ended up stealing the massive shop fan, bringing it into the welding shop, and blasting it at my back while I worked. I stayed dry the whole time! I was, of course, wearing safety glass and a respirator.)

When welding a single frame for a table, it's not terribly difficult to keep things square and true. But when every table leg requires 20 different 4 way welds, and there are 10 tables, you have to streamline things a bit. My personal hero (and CIF Shop Manager) Matthew Hatcher decided to make a jig for the steel table legs. He created it on our CNC router table and applied adjustable clamps to every critical point of the frame. It probably took two hours to make the jig but it saved us well over 15 hours of manual maneuvering.

After we had the sides of the frames created, it was a simple matter of
welding the side frames together and adding some tabs for the table to be screwed down onto.

After that we hit that damned oily steel with another
cleansing bath of acetone so that the shellac we were about to apply would be oh-so-smooth.

Step 3: Getting Them Through the Front Door!

I am going to toot my own horn for moment here... Matthew and I were
each working on different parts of the table welds and then transferring the finished base out of the welding room where they would await the final step. There was a lull when I was waiting for Matthew to finish his part, so I decided I might as well take one of the bases outside and start shellacking it.

The problem was that the table frame was 4 feet wide, 8 feet long, and about 4 feet tall. And made of steel. And steel is heavy. And a lot of steel is a lot of heavy. And as large as they were, they were awkward and unwiedy. Thankfully, we have several rolling chairs at the shop that are low to the ground, with a tool tray underneath - the kind a car mechanic might use. I had the bright idea of propping each end of the table with one of these rolling chairs. Seems obvious in hindsight, but it was a convenient trick to haul these things around the shop! We ended up using this technique for moving the tables into their final home.

Fuse is a programmer's paradise. They have bean bag
chairs, Nerf guns, Ping Pong tables, and craft beer on tap! I'm not going to repeat the dimensions of the tables again (because you may just reach through the internet and punch me); however, given how large they were, the last challenge turned out to be getting the table bases through the door...

Usually with an install like this, we would use the
back or side entrance.

These doors, however, were several inches shorter than they needed to be for us to fit the pieces in. We had to bring each huge frame through the front, gleaming glass doors. It was an incredibly tight fit! Eventually, everything was in the new expansion wing of Fuse, and we started attaching the table tops to the bases.

Step 4: Conclusion

What this job taught us
Working with so many large pieces is difficult from a pure storage and maneuverability standpoint. It would help going forward if we had a large storage rack for holding pieces this big. It wouldn't be a lot of trouble to build something like that; we might do that if we have a similar project in the future.

The rolling and Tipping method works wonders and saved a ton of time.

Creating jigs for accuracy and repeat ability can save you dozens of hours.

Always plan things out (such as making sure you can fit your finished project through the front door... :-)


Storage for a project this large.

Transporting the tables. Despite having our own CIF Workhorse panel van, we had to rent a 27' truck.

Last challenge: having to actually hand these over to the client... These would of looked great here in the Idea Foundry shop! :-)

For anyone that read this far, thank you! This is my first time doing an instructable and the format is interesting. We know and acknowledge there are so many different ways to do things, this is just the way we did it! We are constantly learning from every project!


Brad Hatcher

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