Keyboard 2

The assembly of the keyboard is now complete, although it will undoubtedly need a little more adjustment before it is really finished.

Gluing on the tops of the sharp keys didn't turn out to be nearly as difficult as I had expected it to be.

Here everything is lined up in place ready to be glued - a piece of wood is clamped down onto the tails of the keys at the back of the keyframe to keep everything in place. A steel ruler is used to provide a straight edge to line up the back of the key tops.


The three leftmost key tops are now glued in place.

In order for the keyboard to work correctly the keys all have to be balanced so that they rest in the "up" position and require a consistent amount of force to press them down. This is done by drilling holes at appropriate places in the side of the key and inserting lead weights to achieve the desired effect. Each key is balanced individually by putting a small weight on the front end of the key and then moving a piece of lead up and down along the key to find the balance point. Once that is determined a hole is drilled in the side of the key at that point and the lead weight is inserted. Because the natural keys come in several different shapes and sizes the amount of weight needed and its exact position can vary quite a lot from key to key. The sharp keys on the other hand are much more consistent in size and, on this keyboard, were already almost perfectly balanced.

The only thing left to be done to the keyboard is a final light sanding of the key tops and an oil finish.

Now it's almost time to start thinking about fitting the soundboard but before I do that I want to make sure that everything else is going to fit perfectly.

Note that all stages of harpsichord construction are being closely monitored ...


Here the keyboard and the box guide registers are in place along with the nameboard and the decorative key end cheeks. Both the keyboard and registers fit perfectly.


The end cheeks will need to be carefully filed to match the case once they are glued in place but they too are a good fit and shouldn't present any problems.

A mystery solved ...

I just finished doing the initial sanding of the keytops for the sharps and now they are ready to be glued to their keys.

As I mentioned before, the spacing for the sharps is quite tight in a few places and the C# above middle C has been giving me some cause for concern. There is (just) enough clearance for the key, and I know that with a little careful filing of it and the adjacent keys it can be made to work, but I have been puzzled about why the problem exists in the first place and wondering whether it is because of some mistake that I have made. In particular, I don't want to start filing things to make them fit until I am sure that is the correct way to make the adjustment.

As far as I can see, everything else looks OK - the balance pins are all perfectly straight and vertical, and the keys are all lined up nicely and evenly spaced. I was beginning to suspect that there might have been some small inaccuracy in the way that the keys were cut, but I wasn't sure and then, a few hours ago, I finally saw something that had been staring me in the face since I started working on the keyboard.

Here is a closeup of the problem area of the keyboard:


The problem is that the space between keys 25 and 27 into which the C# keytop has to fit is just slightly narrower than it should be and, now that I have seen it, the reason is obvious.

If you look closely at key 25, just to the right of where the number "25" is written on the key you will see a pencil line running along the right hand edge of the key and disappearing under the keycover at the front of the key. You don't see that line on any of the other keys, and you shouldn't see it because that is one of the marking out lines that indicates where that key should have been cut.

So, the answer is simple - space is a little tight because the right hand edge of key 25 (middle C) is about 1.5mm further over than it should be.

... and, oddly enough, knowing that makes me happy because now that I know what the problem is I am much more confident about being able to fix it correctly. I don't have to win back all of that space - just enough to ensure adequate clearance - taking about 0.25 mm off each side of the C# keytop and the adjacent keys should be more than enough, and I will try to get away with less than that if I can.

Tools

The keyboard is coming along nicely although it doesn't look a lot different than it did a week ago. I wasted quite a lot of time worrying about how well the keytops for the sharp keys were going to fit until I realized that it was pointless even thinking about this until all of the natural keys were lined up and spaced correctly.

Once all of the natural keys were done it became apparent that all of the sharps would actually fit OK. The C# above middle C is a little tight but by the time the keytops have all been sanded there should be enough clearance.

Meanwhile I also spent some time getting my block plane into good working order. I found a very helpful video on YouTube that describes how to do this.



Getting the sole of the plane really smooth took a long time but once it is done it has an almost mirror finish and looks like this:


Seen here with a cat's paw to establish the scale ...


... and, of course, once you have a plane you also have wood shavings ...

Keyboard 1

I am not even going to touch the soundboard for a couple of weeks but there is no reason not to get started on the keyboard.

The first thing to do is to insert the brass balance pins into the middle rail of the key frame. A small wooden block with a hole drilled through it is used to make sure that the pins all end up at the same height and are kept exactly vertical as they are being driven in.



A felt washer is placed on each pin ...


... and we can put some keys in place and start to line up the rear guide.

Each key has a small wooden "thumbnail" which fits into a slot in the back of the key and into the corresponding slot in the rear guide. Eventually these thumbnails will be glued to the keys and carefully shaped and filed so that they move smoothly in the guide but, for now, they are just pushed into the slots in the keys so that I can align the rear guide correctly.

Once the rear guide has been glued in place I insert all of the keys so that I can get an idea of how things are going to line up. At this stage nothing but the rear guide has been glued - the key tops for the sharps are just sitting in place so that I can see how well they are going to fit.


There is still a lot of work to be done to line up, adjust and balance each individual key but so far things are looking very good - the keys already appear to be very level and it looks as if most of the adjustments that will be needed are going to be very small.

Arrival

The kit finally arrived this afternoon - it actually reached San Jose on Monday but sat there for four days before it was delivered.

This is what Zuckermann calls a "Stage 2" kit which means that it comes with the case already assembled.

At the very bottom of the box is the soundboard which, like everything else, appears to have survived its 3,000 mile journey completely unscathed.

I want the wood of the case and the soundboard to acclimatize to the conditions here and not be affected by the fairly large variations in temperature and humidity that I have seen in the garage so the first thing to do is to move both of them inside the house.

The soundboard is safely sandwiched between two sheets of cardboard under the case.

Back in the garage the other parts are laid out so that I can check that there is nothing missing or damaged. Here you can see the keys for the keyboard and the box registers which guide the jacks with the keyboard frame in the background.Here is the brass wire with which the instrument will be strung, lots of little envelopes containing hundreds of pins, nails and plectra and (along with the bottle of "Titebond" and the mylar drawing) pretty much the only thing that you definitely wouldn't have seen in a 17th century harpsichord maker's workshop - a CD containing the construction manual.

In the foreground are the legs for the stand with the music desk behind them along with a cardboard box containing the jacks and, in the background, the curved bridge and moldings.
... and, last but not least, a box of colorful green clamps courtesy of Home Depot ...