Sunday, September 4, 2016

Day 130: Bracing for Fun

After getting the Cheeky Brace installed and proudly sharing it on good, old Facebook, I was smacked around pretty good by a few of the Master Builders, which I happen to like. Their points were well-taken, but the motivation for this particular brace was something Owen Daly of Owen Daily Early Keyboard Instruments had shown me as a way to prevent warping and woofing of the cheek and bentside joint.

Some of the comments were related to the fact that my choice was somewhat, um, unconventional and that its size might cause dampening of natural resonance of the instrument. The thing is, I just want to get this instrument completed and, besides, I would not consider Mr. Miller's bracing scheme, both upper and lower, to be traditional to Ruckers instruments. So, at the risk of screwing things up, I innovated a bit with the entire upper bracing complex by reducing the number of braces and adding the Cheeky Brace, something I believe will serve the instrument well for many years to come.

One of the comments from Owen after seeing the Cheeky Brace was that it was "bigish." Well, I understood this to mean that it simply had too much lateral bulk, so I took it upon myself to chisel, rasp, and file it down to more manageable and, I thought, less dampening dimensions.

This took quite a bit of slow, patient work, neither of which I excel at. I finally got to the point where it was shaped as I wanted, so I cut a brace and glued it up.

It turns out that Owen's comment was related to the thickness of the board I used, not its overall size. He was thinking more in terms of 10mm (roughly 1/2" for my American friends), rather than the 3/4" I used, but I made my assumption and charged ahead. Regardless, I'm pretty happy with the result. In engineering terms, you can see in the photo above where stress from the cheek and bentside will be driven into the cross-brace and held - at least that's the idea. Only time will tell whether this was a good idea or not.

Owen and Bill Jurgenson (a world-class builder living in Germany) were kind enough to share photos with me of original Ruckers instruments on their spines with their bottoms off (I know, it sounds kinda weird). I noticed several things in these photos, including fewer and less bulky braces than in Mr. Miller's eBook Most Excellent and no glue - they simply nailed the braces to the liners. Because I chose to put the case onto the bottom so early in the game, I did not have the luxury of sufficient room to drive nails, so they all got Titebond and clamps.

The final piece to put in was an "upper belly rail stiffener." Now, whether this is a traditional part or not is kind of a mystery to me at this time; it's definitely something I will be looking into when Opus 2 kicks off sometime next year. You can see where the 1/2" x 1 1/2" piece fits onto the upper belly rail in the photo below.

Fortunately, my clamps not only close up, they expand by pulling the top piece off and switching it around accordingly. This prevented me from needing to use nails or screws to secure the piece for the glue-up. Once the stiffener set up, all of the bracing was completed.

This is another milestone that keeps me in the game. It's been slow going at times, but I learn something new just about every day I work on the thing.

Once I completed the bracing, it was time to start on the upper and lower registers. These are the slotted pieces that guide the jacks when they are pushed up by the end of the key. In this case, Mr. Miller recommends a register cutting jig that will reduce the time it takes to produce register slots, so I started making the jig right away.

I'll explain more about this jig in a later post. For now, I'm happy with my progress and looking forward to completing the registers so I can get on to the exacting task of building the jacks (and another attendant jig).

Until next time...

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