Continuing the Keyboard

I spent several hours fabricating more parts: 25 Bolivian Rosewood sharps, 2 arcade blanks, one Maple, one Bolivian Rosewood. I’m still uncertain which combinations of wood to use so I’m fabricating several choices to create some mockups. The comparison of these sharp sets reveals quite a difference in weight. I compared 25 sharp blanks of each type and got these results:

  • Bolivian Rosewood 209g
  • Walnut 165g
  • Mahogany 122g

I don’t want to make the decision solely based on weight and figure I could make up the difference by judiciously carving the keysticks to remove enough weight to make up the difference. So I’m looking for keys that are as light as possible? Ernie said he tried this once with poor results, so I think I’ll stay away from that process.

The next task was to create a couple of mockup keys to compare how they look and feel. Today, in addition to the sharps, I made maple and rosewood arcade blanks. I also milled up 1/8″ keytops (heads and tails) of Bolivian Rosewood. I thought I would make some sample walnut and mahogany tops to create mockups to compare and figure out what I like the best.

Started working on some key mockups of various wood combinations to see what I like. Made 2 rosewood keys, 1 walnut. 1 walnut, 1 rosewood, 1 mahogany sharp. Cut out the mockup keysticks, glued all of the tops on and cut the decorative lines as outlined in Ernie’s Harpsichord Project book. For a finish I decided to use the Birchwood-Casey Tru-Oil. Put on 4 coats all together so far.

Completed the sharp mockups today, with final coats of finish, then buffed with steel wool, then polished with a soft cloth. When I do the actual sharps I’ll fill the grain with the Birchwood-Casey  (Gun Stock) filler and instead of steel wool, I’ll wet sand with 2000-grit paper, then buff to a low luster.

Here are the key mockups, left to right:

  1. Bolivian Rosewood Top with Maple Arcade
  2. Walnut Sharp
  3. Walnut Top with Bolivian Rosewood Arcade
  4. Bolivian Rosewood Sharp
  5. Bolivian Rosewood Top with Walnut Arcade
  6. Mahogany Sharp
Note: the sharps will actually need ‘bone’ tops later
Harpsichord Key mockups

Harpsichord Key mockups

After much thought and discussion with my mentor I decided on the maple arcade as it is more traditional and looks really nice.

Laid out the complete keyboard and laid out and cut the arcade, then attached the arcade to the keyboard blank. So I fit the maple arcade blank to the front of the keyboard. Then I trimmed the arcade flush and trimmed the overall depth of the keyboard to 15 3/16”.  I needed to plane the bow out of the board by hand using a block plane.

Laying out the keyboard

Laying out the keyboard

But here it is all installed and ready to ‘split’ the key sticks apart with the bandsaw.

Harpsichord Keyboard with Arcade Installed

Harpsichord Keyboard with Arcade Installed

About npcarey

Amateur Luthier, woodworker, music enthusiast, software enthusiast
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2 Responses to Continuing the Keyboard

  1. Dan says:

    May I ask how exactly you divided up the keys? In studying manual construction I’m having a hard time figuring out how exactly everything is divided up. If you divide the forward part of the octave by seven and the tail end by twelve, things don’t line up quite right.

    What I *do* know is that BDO specs for organ manuals dictate that naturals F, G, A and B are wider at the front than C, D and E in order to employ “relaxed spacing,” which allows more finger room on the tails of G and A natural. But this just seems odd to me…natural keys of different sizes. Sharps are all 12.5mm wide – all dimensions here represent the cutting line, or “on center” dimension – and the tail dimensions for the naturals are 14.40mm in width for C, E, F and B, the tails outside each of the two groups of sharps, and 15.03mm in width for D, G and A, the tails in between adjacent sharps.

    Please feel free to email me. Just looking for your opinion as well as any wisdom you can or are willing to share on the subject matter. Thank you so much!

    • npcarey says:

      Dan, I’m certainly no expert here. This is my first harpsichord. The ebook I’m working from explains this process is great detail That said, the octave that I am using for this harpsichord is 6.25″ at both the front and the rear, so the division is actually pretty straightforward. The plan according to the ebook is to use a 6.5″ octave at the key head and 6.25″ at the tail. The keys are splayed to make them fit. I’d recommend getting the ebook if you want to learn more about how this is done, but realize that at least in this type of harpsichord the keys are all the same width with the exception of the high D at the treble end.

      Perhaps an illustration will help. This image shows how the 6.5″ layout at the front ‘splays’ to the 6.25″ layout at the rear.

      I hope this helps somewhat. Why is mine different from what is in the ebook? I started building the keyboard before the ebook was finished, and was working from a plan I had from the writer using the 6.25″ spacing. At the end of the day as long as the 6.25″ spacing is correct everything lines up with the registers that hold the jacks.

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