One of the desk bases is complete. The second one is built but needs stain and topcoat.
I’ve been working on the top for one of the desks. As a reminder, here’s the desk design from SketchUp.
The base of the top is 3/4″ oak plywood. Above that is a piece of 1/2″ BCX plywood underneath the porcelain insert. The border of the top is 1″ thick solid oak, with four 5/16″ diameter oak dowels at each joint. The border sits atop the oak plywood. Hence the total top thickness is roughly 1.75″. Solid oak trim pieces cover the edges of the oak plywood.
Below is a picture from when I was testing the fitment of the porcelain insert. There’s a 3/16″ gap between the porcelain and the frame. This is to allow for flexible grout or caulk, since wood isn’t dimensionally stable compared to porcelain.
Yes, that’s a big piece of porcelain. Nominally 30″ x 60″. It’s 6.5mm thick. It has a PEI rating of 5 (the highest rating), so it’s unlikely that I’ll ever scratch it. If it’s good enough for commercial flooring, it’s good enough for my desktops. The design is a marble look, and I continue to be amazed at how far along this stuff has come in 10 years. It’s pretty, and zero maintenance (unlike real stone). Plus it’s manmade; it doesn’t involve carving up the planet. And I can move it by myself.
The downside… my desk base doesn’t meet the deflection requirements for tile or porcelain. That means that until the desk is in place, I will likely not install the insert. And I’m not going to use thinset to set it, since it’d likely just crack. I considered Ditra, but I don’t really trust it to hold the porcelain if I ever move the top later. While I love Ditra, I’ve never tried it in an inverted situation which might occur if two people are moving the top. Plus thinset would make the whole thing even heavier. Note that the porcelain alone is 38 pounds. I’m guessing that the whole top will be more than 80 pounds. My intent at the moment is to use Loctite PL Premium MAX to adhere the porcelain to the plywood. I may change my mind, but I think it’s my best option.
At any rate, I’ve installed the frame on the plywood base with TiteBond III and many cabinet screws from underneath. I also pin nailed and glued the trim pieces (not seen in picture above), which are clamped and curing.