As a hobbyist woodworker/furniture maker, one makes a progression of projects on which to learn technqiues and grow confidence. After I built the requisite coffee tables and book shelves, I moved on to construct something that actually holds people. The futon frame fit the bill. The joinery is easy and the design work can be as simple as a Shaker piece as elegant as something that would befit Louis 14th.

I decided on the Shaker route. The futon frame is simple. The bed is essentially a combination of two box frames with bed slats joined with a piano hinge. The two frames are slightly different in size to accommodate the sitting position where the seat is always shorter than the back. To determine the seat length, I sat in one of our dining room chairs with a ruler pushed against the back and measured to the bend of my knee. The height of the back is the difference from the seat length subtracted from the width of a full size mattress. This explains why people my size are more comfortable in it.

The mechanism for moving the futon from the sitting to the prone position and back is what makes this project a winner. There are futon plans available in every woodworking magazine. I started with one I found in Fine Woodworking, issue 77. The design's mechanism, however, seemed to be clunky and inelegant. This one called for a set of 4 pins, which passed through the arm rest into the bed frame. To change position, all 4 pins were removed by hand and the bed frame, now loose, was moved into position and the pins replaced. A design that requires a person to hold bed frame with one hand and poke a pin through one hole with another is not something that will catch the imagination.

On commercial futons, I found the mechanisms were made of complex sets of hinges and runners constructed of steel, nylon and other materials not available in my work area. Each manufacturer had its own designs, including some that appeared to be modeled on convertible sofas and loungers. These designs are based, however, on brute-force engineering rather than craftsmanship.

The design I used has two sets of 3/4 inch guides routed into each arm rest. The bed frame has 3/4 inch roller bearings mounted on 1/4-20 bolts attached to the bed frame. This rides in the guides while the bed frame moves between the sitting and lying position.

The shape of the guides is critical. In the back of the arm rest the guide is vertical and attaches to the rollers in the seat back so that it's held at a comfortable recline. The lower guides for the seat bottom rollers are based on a modified crescent-shape design, open side down. The back of the crescent is lower than the front, which locks the seat bottom into the the sitting position at a comfortable 8 degrees. The front of the crescent is higher and holds the seat level while in the prone position.

To move the futon from the sitting top prone position, the person stands directly behind the couch and lifts the center of the back part of the futon. Lifting unlocks the lower rollers and starts each moving up the inverted crescent. The seat back is then lowered. While the bottom rollers continue up the crescent to the front position, the back rollers follow the vertical guides down. To go from the prone position to the the sitting position, one person lifts the back, this time bringing the bottom rollers down the crescent. When the back is lifted as high as it can go, it is then lowered locking the bottom rollers again. Cool, eh?