I have wanted to begin the process of building some outdoor furniture for my deck and a concrete coffee table was a great place to start. Eventually I want to upgrade my kitchen’s ugly pink-ish laminate countertops to concrete so this project is good practice for when we take that step. I also had some glow power kicking around my shop for a couple years and it got me wondering if I could make concrete glow.
I first did a couple of test pieces to see if I could get any cool results with glow powder and concrete. I tried a couple different methods of incorporating the powder into the concrete. First I tried sprinkling the glow powder liberally on the mold before the concrete was poured into the mold. The right and middle samples are done in this fashion. The second method was mixing it right into the concrete itself, the sample on the left shows this one. As you can see the samples where I just sprinkled the powder on the mold before pouring concrete into the mold resulted in a much brighter glow. (The other one did glow but my phone camera couldn’t pick it up that well). The areas where the powder was concentrated was a little powdery to the touch. Glow powder would get on your fingers if you rubbed those spots but I figured after I seal the concrete that problem would probably go away…hopefully. Confirming that I could make the concrete glow I started making my outdoor coffee table.
- Glow powder
- Quikcrete Countertop mix (this table used almost two 80lbs bags)
- 3/4" sheet of Melamine
- 4x4 Cedar untreated
- Black caulking and caulk gun
- Concrete fiber
- Outdoor screws, painters tape, rubber gloves, outdoor wood glue, rubber mallet, drill, saw (table saw, circular saw)
- Shovel or something to mix the concrete and something to mix it in.
- Triple Thick Varathane (Satin)
- Odie's Oil
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Step 1: Table Legs
Starting with some cedar 4x4’s left over from another project I started measuring the different pieces I needed to cut. I changed my original design but the sketch shows what I first planned. I cut the cedar down on my miter saw to the size I wanted and drilled holes for screws. After test fitting the pieces together I glued, clamped and screwed the legs together. I was out of cedar at this point so I used a regular construction 2x4 to make a cross support for the two legs. You can’t see this support when the top is on so the color difference didn't bother me. I used a router to create a pocket for the top cross support to sit in. I glued, clamped and screwed the support in. After sanding to 180 grit and clear coating the legs I was done the first part of the build.
Step 2: Making the Form
Next I needed to make the mold for the table top. I used white melamine, black caulking, minwax paste finishing wax, screws an painters tape. Nothing special about making the mold. I watched a lot of Youtube videos of this process (shout out to Mike Clifford @ Modustrial Maker, Ben Uyeda @ HomeMade-Modern, Mike Montgomery @ Modern Builds and This Old House). They give all the tips and tricks I used in this portion. I cut 2” strips out the melamine for the sides of the mold, pre-drilled holes and attached them to the bottom of the mold with screws. After the sides were attached I rub some paste wax along the sides and corners. This helps with the removal of excess caulk. Wiping off excess wax you can run a bead of caulking around all your corners and sides. Doing this will give the top of the table a nice round over. I used the back end of a larger drill bit to smooth out the bead of caulking. When dried you can easily peel off the excess caulking because of the wax I applied earlier. I covered the top of the sides with painters tape so concrete wouldn't cover the screws. Pulling out my small bag of blue glow powder I channeled my inner Jackson Pollock and threw pinches of the powder across the form making sure to really get in the corners. I wanted the outline of the table to glow the most.
Step 3: Mixing Concrete
At this point I was ready for mixing. I used an online calculator to figure out how much mix I would probably need. It turned out to be really close so I would use this calculator again for my future projects. I used Quikcrete Countertop mix, some fiber glass I found on Amazon, rubber gloves, a shovel and a wheel barrel. I started mixing the concrete adding water gradually as I went. You don’t want to make it too runny/watery or you’ll get weak concrete. Go for a thick mud pie consistency. I first put in a thin layer of the mixed concrete and packed it down good. This first layer was around 1/4” thick and had no fibers. I didn’t want fibers to show up on the surface of the table top. After that I added a bag of fiber into the mix (I probably used to much fiber in this table but I didn’t want a partial bag left to be lost in my garage). The rest of the concrete (with fibers) went into the form. I packed it with my hands, screeded it with a 2x4 and tapped the form with a rubber mallet to draw out any bubbles. Covering it with plastic I let it cure for a couple days before taking it out of the form.
Step 4: Finishing
After I removed it from the form I was pleased to see that the glow powder was mostly embedded in the top. The more concentrated spots of glow powder were a little powdery to the touch, just like in my trail run. The melamine makes the top of the table very smooth. The concrete takes on the same slight texture the melamine has. I didn’t feel the need to sand the top down at all since it was nice and smooth and I didn’t want to remove any of the powder through sanding. It looked pretty cool the first time I saw it glowing. The edges really glowed and the powder I spread across the top made it look like I was looking into space or at something like the Northern Lights.
The finish I used Odie’s Oil. This was the first time I used Odie’s Oil and I really like this product. I saw Cam from Blacktail Studio use it on his outdoor concrete table so I figured I’d give it a try. This stuff smells great and is pretty easy to apply. Just stir and apply small amounts with a bondo spreader. Buff the oil in and let it sit for about an hour. Come back and wipe off the residue left with a cotton towel. The glow powder was still a little unstable in the areas where the powder was thickest (I had a small piece flake off). I decided to seal the edges and the powder with some satin Triple Thick Varathane. I was careful when applying this because even with it being a satin finish it was still slightly shinier then the Odie's treated concrete. After I was done it was hard to tell that the edges had a different finish then the top. This sealed the powder better so hopefully it wont flake or rub off anymore. Once that was done the table was basically finished. I had my brother in law come over to help me move it to my deck (its about 140lbs without the legs). The top is not pertinently attached to the legs but its not going anywhere. If I ever do attach them I will probably just use construction adhesive.
Step 5: Done!!
I had a hard time getting some beauty shots because my phone didn’t have a good enough camera to pick up the glow. I borrowed my Dad’s camera and fiddled with settings to get a picture that allowed the glow to show. I apologize for the blurry pictures. I had no clue how to run the camera or what settings to use but I managed to get a few usable shots. This was my first project I’ve posted here so I hope you enjoyed reading the process. Thanks for your time!
Participated in the
Stone Concrete and Cement Contest