Tuesday, January 26, 2016

Day 113: Dados and Rabbets

Just before this last weekend, my laptop's Windows 10 decided to update on its own. At the same time, a message popped up saying Windows Defender needed to run, so, trusting bonehead that I am, I let 'er rip. The result: My computer took such a big, horrific dump that it trashed the BIOS on the machine. I can't even get to Windows to fix it because the machine goes immediately into repeated alarm mode on startup. This has prevented me from updating you, my beloved followers, in a timely manner. Please accept my sincerest apologies. I was able to set up a profile on my wife's machine (while promising not to trash it), so here goes the latest.

Over the weekend, I worked primarily on the dados and rabbets (or rebates for my friends in the UK) for the various boards and beams for the cheek and spine. As you might recall, the cheek is the short piece that runs from the keyboard to the bentside and the spine is the long piece that runs from the keyboard to where it joins the tail. Mr. Miller's eBook Most Excellent has me cutting 1/4" dados and 9/16" rabbets into both to provide insets for joining up the pinblock (wrest plank), name board, and lower belly rail.

This was an interesting exercise because I do not own a 3/8" top-bearing router bit as suggested by Mr. Miller. I do, though, own a trim router and a 1/4" router bit, so I decided to set up guides and use the thing to get the job done. It turns out this was not one of the best ideas I've had so far. It will be okay in the end because, fortunately, I will be veneering the inside and outside of the case with an astonishinly thin quarter sawn red oak paper-backed veneer. This will hide some of the roughness of the cuts, but I certainly will not head down this path in the future, choosing, instead, to pick up that 3/8" top-bearing router bit.

The first step was to measure the width of the trim router guide offset, which ended up being 1 5/8" on each side. I then clamped a small board to a piece of scrap and ran a test cut.

All went well and I also learned that this process produces sawdust nearly on the level of sanding, so I went ahead and donned my HEPA filter mask, which always gives me the Mad Scientist look.

I enjoy this because it's the only time in the workplace I get any respect for having earned a doctorate.

The next step was to jump into the process and start carving out the dados.

The clamped boards in the photos above are guides for the trim router. This worked pretty well, but I would have much preferred tacking a guide onto each as described in Mr. Miller's eBook Most Excellent. The cuts are not horrible, they're just not perfect and I believe the top-bearing router bit would provide a much cleaner, more reliable cut. I will absolutely need to do this on the next one because they're going to be selling snow cones in hell before I veneer another harpsichord case side. Regardless, I charged ahead.

I actually cut the rabbet on the end in the last photo above using the table saw because it required a 9/16" deep cut, rather than 1/4" and I wanted to leave the router and table saw set for the spine work. As you can see below, it worked out pretty okay in the end.

On a completely unrelated note, I visited my friend, Roger Green's, shop as part of a Clark County Woodworkers meetup, which is an offshoot of the Guild of Oregon Woodworkers. We who live all the way up in North Clarkistan get together once a month in a selected member's shop to observe each other's work and generally lie about how much we know. Last week, I got a gander of Roger's beautiful Roubo-inspired, French white oak workbench. Bravo, Roger - nicely done!

While I do have a little 5' x 18" workbench anchored to one of my shop walls and the assembly table squats in the center of the room acting also as the bottom of a go bar clamping setup and the outfeed table for the table saw, both are really too high for my burgeoning purposes; those purposes are centered on doing increasingly more work with hand tools - hand planes, scrapers, etc. This requires a lower workbench to reduce back and arm strain, both of which I enjoy on a regular basis after spending any length of time in the shop.

After seeing how such a bench would benefit me in so many ways, I picked up Chris Schwarz's The Workbench Design Book on how to, well, design the perfect workbench. Schwarz recommends the top height of your workbench meet at the place where your pinky connects to your hand when you hold your arm comfortably at your side. This is a pretty low bench that also offers hand plane storage and multiple clamping opportunities using leg and end vises, as well as a "deadman" for holding your work and dog and hold down clamps. Yes, this design is old, but it's time-tested and it would, I believe, alleviate much of the back pain I experience (and don't talk about here) after working in the shop. Watch for this mini-project to kick up over the next few months.

Until next time...

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