Height adjustable knock down couch / standing desk
I have built a total of five desks like this so far. The first two here, then another two that I built here (one of these I gave away), then another for a friend (didn't take pictures). Two are in use in the house (see them here and one in my big workshop garage see here). I wanted another one to take to my in-laws to get some work done there.
I built this one out of hardwood, mostly maple. Most of the wood came from large shipping pallets. You can see some of the nail holes in it. So in a way, it's a pallet wood project, but with planed wood so it doesn't look like crap.
Cutting the wood to lengths using my large table saw sled, then squaring and straightening the pieces and planing them. It's usually more optimal to do the planing before cutting to length to avoid snipe, but if there is any twist or bend to the wood, it's less wasteful if it's cut to length first. Thickness planer snipe can be avoided by feeding the pieces through back to back.
I needed three dadoes just over 15 mm wide, with precise 30 mm spacing for the vertical adjustment part. I set the fence by measuring from the blade with callipers. I marked the tooth I measured from so I could make later measurements from the same tooth for consistency.
I usually don't bother setting up a dado stack, but needing three identical dadoes in each of four pieces, it was worth the trouble. The initial fit I got was precise, but too tight. I needed a loose slide, so I re-cut all the dadoes with the fence 0.3 mm nearer to the blade than last time to widen the slots.
In retrospect, maybe I shouldn't have bothered setting the dado to the right width and just planned on getting the right width by making two successive cuts. Setting a dado to width is so much trouble.
I'm joining the leg parts together with mortise and tenon joints, using the metal pantorouter. Normally I'd have one big tenon, but I wanted to try these plastic tenon templates. They are smaller, so I used two of them.
With a long 1/2" spiral bit in the router, I ran into some vibration problems when sweeping side to side. So I cut these by making a series of plunge cuts. First on either side, then in the middle, and then between my previous cuts. After that I moved it side to side while slowly plunging in to clean the cut.
I only had four joints to cut. Even the identical joints weren't quite identical because they are a mirror image of each other, so I had to mount one piece one way, the other the other way around (the mortises aren't laterally centered). So it was easier to just make a line on the wood where the mortise goes and line it up to that instead of setting up stops.
The tenons are towards one edge of the wood so that the corresponding mortises are closer to the center in that piece. A lot of material needs to be milled away, so I cut most of it off with a table saw and bandsaw before milling the tenons.
The bracket is joined with a bridle joint, which I'm cutting with my quick set tenon jig
I'm adding some dowels as alignment pins for this bracket. I started by drilling 1/2" (12 mm) holes in the corners of the bracket, then I clamped the bracket to the legs, and used a hand drill to drill just a millimeter into the leg parts.
I drilled a hole every 3 cm along the legs for bolting them together at different heights. I marked these off with a tape measure. Before drilling them, I also used a very thin blade to cut a shallow groove along the slot where the holes go, to help me center the drill.
I then used these small holes to line up the drill from the other side and finish the holes. No tearout this way.
I then moved one piece by 1.5 cm and did it again, so that I had holes marked every 4.5 cm.
With holes every 3 cm on one part, and holes at 4.5 cm spacing on the other part, I can lock the height at 1.5 cm increments by putting the bolts through different holes.
Here scraping off the old varnish (there was much less of it on the back)
The wood has a solid wood core, but with two layers of veneer on either side. One layer is perpendicular to the grain. This makes these boards act more like plywood, in that it prevents sideways expansion and contraction of the wood.
Because of this, I can put trim around it without having to worry about what happens when the humidity changes
I'm using the template feature of this jig to repeatably cut the fingers of this joint. A bolt (in my right hand) needs to be lifted to move from one notch in the template to the next. More on that here
I actually drilled the holes in the legs and back brace with a drill press, but used a hand drill to drill slightly through to transfer the locations.
I'm using a big scrap of wood with a notch cut in one side as a drill guide and depth stop. It keeps the drill perpendicular, and once the drill's chuck hits the block of wood, I know I have drilled deep enough.
The intended use is for it to be a really low desk that I can pull up to a couch. And for that, it needs wheels. For this one, I'm using rollerskate wheels (I get these for free from discarded in-line roller skates).
A 5/16" (8 mm) bolt fits snugly in the bearings. I'm just screwing this bolt straight into a slightly undersized hole in the wood.
Large knock-down table (easy to take apart for moving)
Compact computer / monitor stand
To my Woodworking website.