This desk is made with a welded aluminum frame with a wood work surface. The picture below shows the layout of the frame including the underside of the work surface.

The aluminum tube is 1" square extrusion with 0.060" walls. Aluminum was used to reduce the weight. All of the right angles are mitered at 45 degrees to increase the weld area for strength. The two vertical braces are just butt welded between the longer cross tubes.

Both the front and back edges of the work surface are sanded round to make it more comfortable to rest hands and wrists across the edges in use.

Self adhesive felt is applied to the areas in contact with the chair to protect the finish on the chair and it slides comfortably on the armrests of the chair without scratching the wood. Plastic caps seal the ends of the tubing and cover the sharp edges and corners.

With the exception of the stain for the wood and the spray paint, everything for this project was in my stock pile.

When sitting in the chair, the bottom surface of the frame cross tubes sits an inch or so above my legs. The back edge of the work surface is a comfortable distance from my shoulders to use the keyboard and there is room between the laptop and the chair for flash drives, a mouse and a beverage. The end result on this lap desk is that it is comfortable using my laptop on or reading a book on. It is light enough to be easy to handle when getting in and out of the chair. There is a footrest in front of the chair that makes a convenient place to set the lap desk while plugging in the laptop or getting up. The height and dimensions worked out well considering that it was made from a drawing sketched on the back side of a receipt from the metal yard.