I described the beginning of the desk project in Part 1.

The horizontal rails fit into pockets in the leg assemblies. I cut the pockets using the same template and router guide bushing technique as I used on the bookshelf supports.

 

The corners are squared up with a chisel later.

 

Before gluing the rails into the leg assemblies, I needed to scribe1 the legs to the floor. I already knew the floor was not flat. It’s just vinyl plank over the basement concrete. I didn’t want to do my glue up without fitting the legs to the floor, because the result would be guaranteed to be out of square.

Using a laser level2, I checked the spots where legs would sit, and found the lowest and highest spots. There was about ¼” difference. I had actually planned ahead for this, and cut my legs ½” long of required length. The plan was to set the legs up where they will eventually be installed, prop up the low spots until the legs sat level, then mark the legs at the high spots and cut them back.

To allow fine adjustment of the height, I drilled a countersunk pilot hole in the bottom of each leg, and put in a drywall screw. A slight turn in or out allows for adjusting the height in very small increments.

 

 

I’ve tried leveling cabinets, etc. using framing shims to adjust the height. The screw method allows better control and repeatability. After getting all three leg assemblies sitting plumb and level, I used a custom engineered marking tool3 to scribe a line all the way around each leg.

 

Legs assemblies in more or less correct locations.

 

Incidentally, here you can see one of my stupid mistakes4. In this case, it was the leg I glued up out of cherry and maple scraps. You can see the offending leg in the pictures in the last article. My assessment that the leg would not be readily visible due to where it would be installed was very wrong. After a disastrous attempt to stain the maple, I ended up cutting a channel in the wide face and gluing on a scrap of oak faced plywood. You can still see the maple on the sides of the leg, but it’s much less obvious. You also see there is a shoulder cut into the top corner of that leg. I’ll come to that later.

Attempting to cut directly to the marked line with a saw was an objectively bad idea5. Instead, I hogged out material from the center of the leg with a Forstner bit. Then, I walked around the marked line with a chisel, to remove maybe 1/8” of material from the outside of the leg. Finally, I ground out the rest with a coarse sanding drum on a Dremel tool.

 

Leg marked for trimming.

 

With all the legs cut, I stood them back up and checked level again, then glued the rails in place.

 

Cardboard to protect floor from drips of polyurethane glue.

 

The long section has legs at one end, but the other end hangs from the front rail of the short section. I considered trying to make that joint by gluing the long rail into a pocket in the short rail, but had concerns how well that would hold up over time. I also didn’t want to weaken the short rail by cutting material out of it. In the end, I decided on mechanical fasteners. That is, some big fat bolts.

I cut a 2’ piece of angle iron and fit it on to the end of the long section. This piece goes under the angle iron in the long rail, so it will carry the whole load of that end of the long section.

 

“Hanging” end of long section.

 

I clamped that end onto the short section, and drilled holes for bolts. The holes are located such that they go through both the angle iron on the end of the long section, and through the angle iron on the bottom inside of the short rail. I had intended the end of the long section to rest on that shoulder cut in the ugly leg, but after I got everything lined up, the shoulder turned out to be about 1/32” too deep. I don’t think it’ll matter.

 

Long section connected to short section.

 

You can see here that, in an act of complete overkill, I’ve glued angle iron to the back rails also, and screwed the back rails to the wall through that angle iron.

 

Frame completed and installed.

 

Despite my best efforts, my rails are not flat or level between the leg assemblies. The pockets in the legs are a little too deep, so the tops of the rails sit below the tops of the legs. Also, after I cut the rails, the wood started to move around a little. Specifically, the short front rail bows down and in. The angle iron glued to the bottom pulled out some of the bow, but not all. To prevent the desktop from sagging down to the level of the rails, I needed to provide some support.

I got out my mostly-trustworthy 8’ straightedge, and mixed up some two-part epoxy putty. I used System 3’s Sculpt Wood putty. Every 8” or so, I put a blob of putty on the rail, and covered it with a scrap of kitchen plastic wrap. Then, using the tops of the legs as reference points, I used the straightedge to smush the blobs down until they were level with the legs.

 

Epoxy to provide flat level support for the desktop.

 

For the desktop, I could have tried to go really classy and glue up hardwood tops. Or, somewhat less classy and used hardwood faced plywood. But this is a utilitarian desktop, and I’m messy and somewhat careless, so I went with a material that is durable and easy to clean: melamine6. Melamine is a hateful product. The plastic face is brittle at the edges, it’s sharp where it has chipped or been cut, and the core seems to have been made from floor sweepings. Seriously, sometimes you’ll find little bits of metal and debris inside. You need a special blade to cut it, or you’ll get little chips in the plastic all along your cut line.

Because it is so easy to damage the edges of melamine, 4’ x 8’ sheets come oversize by an inch in both directions. I ripped a sheet down the middle to get two pieces, each 24 ½” wide, with one good edge. I planned to put the bad edge against the wall and cover it with trim. I knew the walls weren’t flat, and was not inclined to try scribe melamine.

Test fitting my two pieces of melamine, I discovered that, again, despite my best efforts7, my desk sections didn’t meet at a square angle. I measured the angle and trimmed one end of one piece accordingly. More test fitting, and then I trimmed both pieces for length. If you actually measure, the overhang is not uniform all around, but it’s close enough that it looks okay.

To band the edge of the melamine, I took a 3’ scrap of quarter-sawn oak and ripped it into pieces about 1” by 3/8”. I ripped it so the quarter-sawn figure showed on the 1” face. I worked my way around the exposed edges of the top, gluing on banding, using 45 degree lap joints.

 

Clamps on the banding. Did I need so many? Maybe not.

 

Here’s a short rant on so-called parallel jaw clamps. They aren’t. I used the clamps “upside down” so just a short bit of jaw was grabbing the top of the banding. Otherwise the clamp jaws would have put more pressure on the part of the banding that hangs down below the melamine, and pulled the oak away from the melamine at the top. I tried to get the top of each piece of banding flush with the top of the melamine, and mostly succeeded. I went around after and sanded down the high spots. Then I rounded the top corner with a router, and varnished the banding.

To make sure the two pieces of melamine would line up without a ridge sticking up, I cut a ¼” slot in both pieces and made a spline out of some ¼” scrap. A test fit showed that the joint lined up very nicely, including the mitered ends of the oak trim.

 

Joint with spline in place.

 

And here’s where I made probably my biggest mistake8 on this project, and it’s frustrating because it’s a mistake I make all the time. During dry fit, the spline fit in the slot snugly. Too snugly, as it turns out. You have to leave a little room in a joint for glue. By the time I got glue on all the surfaces and tried to pull the joint together, it wouldn’t close up all the way. Not for lack of trying. There was a lot of cursing. Then hammering. Then more cursing. My wife heard it upstairs. In the end, I was left with about a 1/32” gap along the whole length of the joint. I filled the gap in the oak trim with epoxy putty, mixed with a bit of stain to get the right color. The gap in the melamine I will fill with a white epoxy putty, when I get my hands on some.

To secure the top to the frame, I didn’t want to try run screws directly into the melamine because the particle board core is so shitty, I was afraid the screws would pull out. I glued some scraps of ¾” plywood to the underside of the melamine. I roughed up the melamine with some 40 grit sandpaper first, and used the polyurethane glue again. I drilled holes in the angle iron on the back rail, and glued some little scraps of angle iron to the front rail and drilled holes in those also. Last, I ran screws through the angle iron into the plywood.

 

Desktop from underneath.

 

The last thing was to cover the gap between the desk top and the wall. I dug into the big pile of scraps9 and got lucky: a 9’ piece of white oak, about 1 ½” usable width. I ripped it into pieces about ¾” by 5/16” and pre-varnished those. I tacked them to the wall with little finish nails, again making joints with 45 degree laps.

 

I guess it looks alright.

 

And that is pretty much it. I still need to drill some holes for cabling, and hang some cable management on the underside. But otherwise, I call it done.

 

1  Is scribe the right word here? I don’t know.

2  That has since ceased to work, and the manufacturer regards it as disposable. Screw you, Klein Tools.

3  A utility blade clamped onto a piece of ¼” scrap.

4  That I’m willing to admit in public.

5  I know this because I tried it.

6  Melamine is a low grade particle board faced with a hard plastic, usually white, on both sides. Most cubicle desktops are melamine with vinyl banding.

7  I should stop saying “despite my best efforts.” Apparently my best efforts suck.

8  Worse than the janky leg? I think so.

9  The pile on the lumber rack, as opposed to the small pile of scraps laying on the shop floor.