Introduction: Natural Rock Coffee Table

By Sam DeRose
About: Freelance mechanical engineer from the Bay Area.

This summer we refurbished our arbor and outdoor sitting area, and one improvement we made was investing in some high quality patio chairs. The complete set included a matching coffee table, but it was so expensive that we just got the chairs. This got us thinking about making our own coffee table to accent the chairs.

After some brainstorming, we decided that a natural rock table would look nice. The frames of the patio chairs are black metal, so we figured a simple black steel stand made out of square tubing would look good.

This rock coffee table is a great weekend project because it only takes a couple hours of work, and the result is functional and extremely professional looking. 

Another great thing about this project is it only cost about $60 in materials!

Step 1: Choosing the Rock

On Saturday morning we headed over to our local rock supplier (Shamrock) and sifted through their flagstone selection. It took about 40 minutes to find a piece that was the right shape, size, and color. Our rock was 65 pounds and only cost 15 dollars. We also purchased some brush-on sealant because since we are using the rock as a coffee table, we didn’t want spilled drinks to stain it.

Step 2: Seal the Rock

Follow the instructions on the sealant and seal the rock. We got a water-based sealant and applied two coats with paint brushes. It was super easy to put on, and didn’t change the color or texture of the rock at all. The sealant definitely works because after we applied it, water droplets beaded up instead of absorbing into the surface.

Step 3: The Stand

The stand was entirely made of 1 inch steel square tubing. We got our steel from Orchard Supply Hardware, but most hardware stores like Home Depot or Lowes have this material.
We used a combination of a cutoff wheel on a hand held grinder and a bandsaw to make all the cuts in the metal. We used our 120 Volt Hobart MIG welder to tack and weld everything together.

We used some paper to trace out a design of the stand directly on the rock. We chose a triangular stand instead of a rectangular one because one: the rock is more of a triangle than a rectangle, and two: tripods are stable on uneven surfaces. This second reason was more important to us because this table will be sitting on uneven brick, and we didn’t want to have to constantly adjust and shim the legs to prevent the table from tipping and rocking side to side.

The one downside of making a triangle stand is that there are some funky angles that need to be cut into the steel cross pieces (the pieces spanning between the legs).

The pictures will illustrate this better then a textual explanation, but this is basically how we tackled this problem of cutting weird angles: We tacked one cross piece to each leg, which gave us the entire stand in three pieces (each piece being a leg and a cross piece). Then we took these three pieces and arranged them on the paper template, and using a ruler and sharpie, marked the correct angle onto the cross pieces so they would match up nicely with the adjacent leg. After these angles were cut, we tacked the whole thing together, and once it was assembled, then we went back over each joint and welded the whole joint.

After cleaning the metal with some steel wool, we applied two coats of semi-gloss black metal spray paint. Done!

Step 4: Install and Admire Your Work

Simple position the stand where you want the table, and then set the rock on top. The rock is heavy enough and there is enough friction between the stand and the rock that it won't move around.

If you really want, you could glue some thin foam padding on top of the stand to provide some cushion, or glue blocks underneath the rock so it registers with the stand and prevents sliding. It works fine as is though!