Making the Keys

The keys are made of poplar, with hardwood faces (birdseye maple for the white keys, and ebony for the black). The poplar key bodies were cut from a single piece. Each key drops over an eighth-inch SST (stainless steel) dowel pin in the center rail -- and another one on the front rail. These keep the key aligned while permitting it to move.

All the rails are (will be) covered with self-adhesive felt to silence the action.


Making the Frame

The frame consists of three rails. The keys "teeter" on the center rail.

 


Milling the angle on the midrail


Assembling the key frame.

Making the Keys

The process was:

      • Lay out (draw) all the keys
      • Drill the pivot and guide holes
      • Saw the keys apart
      • Glue the key faces on:
        The key faces were first positioned with double-sticky scotch tape, then drilled for 1/8" dowels. Finally they were glued in place with urethane glue.

 


First, I laid out the keyboard on the blank. The keys are made of poplar, and started out as a single board, grain running the length of the keys. The board is made of several pieces, carefully joined so the joints fall between the keys.

 


This keyboard blank is set into the frame (see the last 2 pictures on this page), shimmed to center it, and then frame & keys are line-bored for the dowel pins which will form the guide pins and the pivots.

 

 


The pivots will receive an additional guide plate on the top of the pivot pins -- formed of white Delrin©. The slots are milled in the Delrin©. Next, the individual keys are cut apart on the bandsaw on the lines visible in this photo. (The Delrin© is cut at the same time)


The bandsaw marks are removed by taking a "cleanup" cut with the mill on all sides. The overall spacing between adjacent keys is about 0.050"

 

 


Cleaning up the sides of the key. You can clearly see the undercut here for the bird's eye maple key faces.


Cleaning up the corner of a white key.

 

 


Next the blanks for the white key faces are prepared. I decided not to use ivory (or ivory-colored plastic), opting instead for bird's eye maple. It will be given a natural-color finish, and I hope will contrast nicely with the ebony of the black keys. Here, the underside angle is cut on the front of the key.


Trimming the side of the white-key faces. The 2x4 in the vise is a jig to make it easier to cut all the blanks the same.

 

 

At this point, I was left with a challenge. I wanted the key-faces to be absolutely straight, but the underlying poplar key bodies were ... well ... less that perfect. I needed to apply the keys to the bodies very, very accurately. How I did it was to arrange the key faces upside down in a tray and then transfer them all at once to the key bodies. Like this:

 


Now came the task of establishing uniform spacing between the keys. I wanted them to be as accurately spaced as possible -- so I used a 2 step process: 1) align the key faces in a temporary "tray," and 2) transfer them to the poplar key bodies Here, you see them being "test-fit" in the temporary tray.

 

 


Here's a close-up of one of the key faces.

 

 

 

 


Narrow strips of double-sticky scotch tape (the orange stuff in the picture) were used to temporarily attach the key faces to the temporary key tray.

 


Peel the backing

 


Inserting the key faces. Washers were used to establish 0.050" spacing between the keys. Normal hardware-store grade washers have quite a thickness variation -- I selected the right thickness to fill all the available space.

 

 

 


Detail showing the spacer washers.

 


The assembled key tray. The key faces are all upside down.

 

 


Now, to transfer the key faces to the key bodies, the first step is to remove the rails.


Removing the rails from the temporary key tray. Note that the key faces are upside-down here ... the exposed surface is what touches the key bodies -- the chamfered end is the front.

 

 


The Key faces will now be transferred to the key bodies. Not obvious in this photo is the double-sticky scotch tape applied to the keys. (Its white backing hasn't been peeled off yet)

 


Test-fitting the keys, before I peel the tape backing off.

 

 


NOW, I peeled of the backing ...


... and applied the key faces to the keys.

 

 


Firm pressure forms a stronger bond to the key bodies than to the temporary tray.

Key faces in place.

 


With a little gentle prying, the temporary tray was coaxed off the key faces. The narrow strips of double-sticky yielded easily leaving the key faces firmly stuck to the keys.

 

 

To make the attachment permanent, the key were drilled and doweled from behind with 1/8" poplar dowels. The double-sticky tape was removed, and the faces were glued in place with urethane glue. .

 

 

 

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