Whether you're trying to balance a laptop on your knees or just need somewhere to park your TV dinner, a lap desk can be a handy solution to a frequent irritation. But laps, chairs (and bellies) come in a million different shapes and sizes, which is why the store-bought lap desks I've tried were either too shallow to hold my computer, too wide to fit between the arms of my chair, or otherwise incompatible with my "shape." 

So I designed one that fit.

Now I finally have one that is wide enough to span my knees but narrow enough to fit between the arms of my chair. It has deep side wings to help counterbalance a heavy computer, and a rounded belly socket that fits me comfortably. But you may need different dimensions, so I designed it with customization in mind. Just change a few settings at the top of the OpenSCAD file and make a dock that fits all YOUR spaces.

The puzzle-piece design means you aren't limited by the size of your build plate, and they interlock so snuggly that the whole thing is surprisingly sturdy. (My wife and I have been using ours for over a year now without any issues.) If you're worried about it, a bit of CA glue will lock it up tight, but if you leave it as is, a disassembled Space Dock will fit easily into a suitcase, so you can take it with you on your next holiday or business trip.

Dial it in

Since this is a fairly large print, you should dial in the tolerances before you print. In particular, you probably want to test the friction fit between the interlocking pieces. If the gap is too wide, the desk won't stay together. And if the gap is too thin, you won't be able to assemble them without serious violence.

There are two basic ways to test the fit:

The Lazy Way: Print pieces 4 and 7 and be sure they fit together snugly. If they do, you've already got two useful pieces done, so you're ahead of the game.

The Cautious Way: Load pieces 2 and 5 into the slicer and then lop off everything but the interlocking edges and maybe 1" of material on either side. Print those and then test them for fit. Even though this test will not leave you with usable parts, it's a better test because as you increase the number of lugs being fit together, the overall friction goes up too.

When I printed mine, the Lazy test was reasonably snug, and the Cautious test needed the gentle attentons of a hammer. For me, that turned out to be perfect, and I haven't needed to glue the pieces together to keep them from sliding apart.

Build Plate

Be aware that the 8 jigsaw pieces in the STL were sized to fit the build plate of a Prusa MK3S+. If your build plate is smaller, you'll need to change the build plate params at the top of the OpenSCAD file and export your own STL.

Print Settings

I printed mine in PLA, with a 0.4mm nozzle, at 0.3mm layers with 5 perimeter shells and it has held up just fine for over 2 years now.