May 22, 2012

Preparing to finish the legs for the stand-up desk

It has been very cold in NW Missouri, which prevents me from using the finishing room to complete the spraying of the toner coating on the dust cover for the desk; I would have to open windows to bring make-up air into the shop (the exhaust fan pushes out 2,200 CFM – a complete change of volume in the shop every 5-1/2 minutes!). So, for now, the dust cover sits in the finishing room, where it is a cozy 74°F. Meanwhile, after many hours shoveling snow, and pushing it around with the tractor, I finally got into the shop again today. And I turned my attention to some pre-finishing on the walnut legs.

Garnet shellac enhances the color or walnut. That is what I will apply as the first step in the finishing process, using lint-free rags. But first, the sanding dust must be removed, using moist lint-free rags:

As soon as the wet rag hits the wood, the grain “raises” and the wood surface becomes rough. I use 600-grit sandpaper with light pressure to remove the raised grain, and make the surfaces smooth again:

The garnet shellac I have been using for several years is Target’s Ultraseal-WB, a waterborne, dewaxed shellac that seems to meld with the Target topcoats; notice the gorgeous color imparted to the walnut by the garnet shellac:

Because the Ultraseal-WB contains water, the wood grain will again raise, but only slightly. With two applications, the coating can be sanded smooth, without cutting through the coating into the wood. I will check results in the morning, and continue with the finish. At this stage, only the garnet shellac will be required, and the legs will be ready for initial assembly of the desk.

Al Navas

The stand-up desk: Double tenons for the leg stretchers, using the FMT

With my left shoulder on the mend (keeping fingers crossed…), and not having to lift above shoulder height, I decided to use the Leigh FMT to make the joinery for the end stretchers. These will connect the front legs to the back legs on the stand-up desk. Later, I will use a medial stretcher to connect the end stretchers.

I normally make at least five legs for a large piece like this desk. As usual, I use this extra leg, and a “spare” stretcher, to fine tune my setup with the FMT. I suggest you do the same with all joinery, as it will save many headaches. All dimensions on the spares are identical to those of the actual work pieces.

The photo below shows the twin tenons allowed by the 2-inch thick stretcher, just as I finished machining them – the tenons are 3/8-inch thick, 1-1/2 inch wide, and 1-1/4 inch long:

stretcher-tenons-target-view

The tenons aligned on the mortises:

stretcher-double-tenons-2

And, finally, the first dry fit:

stretcher-double-tenons-3

The fit was a little snug; but that is not a problem, as I can tweak the fit in 0.001″ increments. Now I can move to making the joinery on the real legs and end stretchers. Late in the day, I decided to wait until morning to do the real thing.

.

Page optimized by WP Minify WordPress Plugin