I’ve had a project I’ve wanted to do for a long time to help out around the shop—to make an adjustable height table. The adjustable height will be useful as an outfield table for my table saw or bandsaw, or to help maneuver equipment to and from the tailgate of my truck, or as an extension to my workbench. I also wanted it to be super-heavy duty and to withstand several hundred pounds of weight. The horizontal surfaces are constructed from laminated pine milled from 2×12’s and the legs are made from 3/4” birch plywood. I used a normal automative jack to raise and lower the table, but I opted for a jack that had surfaces that would be good for attaching the jack permanently and also a socket to control the lift. Making mechanical pieces from wood is tricky because wood is not very stable, it expands, contracts, twists, and warps. To accommodate for this, the legs were made from high-quality plywood to resists changes in shape and dimension. Also the legs are intentionally not extremely tight fitting to prevent possible binding when adjusting the height. I slathered the legs with floor wax to reduce friction to help movement as well. Overall, it works pretty well. It has a lowered height of about 28” with a raised height of about 46”. The table itself is very heavy, about 150 pounds and it should be able to carry a 500 pound payload with ease.
You can find the SketchUp drawing on GitHub.