I am planning to make a concrete top surface for my computer desk to install in the shed-office that we are working on. We have a month or two before the shed is converted, so I have some time to get a grip on how large a project the concrete desk would be, and give me time to size up my skills. I need to know if the project is futile before I begin. This is a big project that will take a lot of planning, learning and time on my part.

The best way to learn is to do, especially with DIY projects.

For my first ever foray into working with concrete, I decided to make a small rectangular brick of concrete, with some decorative glass beads embedded in the surface. Last night, Qais and I used a small section of particle board and some foam core to build a rigid, smooth form to pour the concrete into. It’s about 12″ x 18″ x 2.5″, sided with duct-tape, and the interior joints lined with %100 silicone glue. The foam core should provide a smooth-enough surface to test against, and the silicon glue should keep any moisture from leaking out of the form. The form’s depth is about as deep as I expect to make the desk surface. I also got a 40 pound bag of #1101 Quikrete mix, which is usually used for setting fence posts and making patio steps. It hardens to about 4,000 psi when properly mixed and fully cured.

Today I mixed and poured the concrete into the form, in very small batches. I did this again with Qais’s help. I think it worked, and the concrete slab will setup properly, but there are a number of important lessons learned for next time:

• I need a finer concrete mix – the aggregate in #1101 is too coarse
• A real mixer would be better to use than my gloved hands
• I used way too much water. A mixer will help me keep this balanced
• Put the glass beads in before mixing the concrete
• Don’t rely on the attention span of a three year old

So, the form is full of wet concrete that is setting up. I’ve purchased a 5 gallon bucket and an 80 lb bag of Quickrete 5000 Pro Finish mix, so the next attempt will be either tomorrow or next weekend, with better concrete, a better designed mold, and a more consistently mixed concrete. If it’s tomorrow, I’ll post an update with pictures.