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Orchestrelle, Chapter 15.1
Rebuilding the Æolian Orchestrelle
58-Note Player Reed Organ, 1912 Model "W"
by Richard Vance
Copyright (C) 2000 by Richard Z. Vance
rev. A, 26 November 2000

Chapter 15.1 - The Spoolbox

    This cross section shows that the spoolbox assembly seems to be absurdly complicated, but Aeolian must have had their reasons.  Two features about the tubing are important.  First, the tubing inside the box must be brought outside, in a way that does not cause leakage of the wind from inside the box.  Second, the spoolbox and the manual valve box are outside the swell box that surrounds the reed ranks, but the primary and secondary valves are inside the swell box.  The big vertical board on the back of the spoolbox forms part of the lower wall and floor of the swell box.  I always wondered how the tubes got through the swell box envelope, but now I see the clever way they did that.

    This spoolbox I got with the organ may well not be the one originally fitted, since the player had been removed at one time.  This box may be an earlier model; the black finish and brass tracker bar places it after 1906, but it came with a tempo scale in the bottom.  This is characteristic of earlier instruments which used a drawstop rather than an indicating arc lever like mine, to set the tempo.

    The spoolbox had been stored, perhaps in damp conditions, and the black shellac finish was not only crazed, but had the little white cracks all across, indicating water damage.  So the whole thing had to be refinished.  First it was all taken apart and the old gaskets washed off.  The two sides, the bottom and top, the upper and lower back panels, the two thin covers over the tracker bar tubing, and the cover frame (all in one glued together piece) were refinished with sandable primer and Sherwin-Williams black auto enamel, as described in Chapter 14.1.  The only difference is that these pieces were already finished, and had to be stripped.  This is essential when redoing any black player finish; the old shellac will interfere with any new finish system that is attempted.  Following D. L. Bullocks advice, I used a liquid methylene chloride based stripper, rather than the modern paste or safety strippers.  Just slop it on and wrap the wet pieces in plastic to prevent evaporation.  After an hour, all the shellac was softened, and could be easily scraped off.  Follow this with a wipe down with paper towels and more liquid stripper.  The wood is left perfectly smooth, without any lifting of the grain that occurs if "water washable" paste strippers are used.  It is a lot easier to "rub" the finish with polishing compound, if the piece being rubbed is screwed to a scrap board to hold it steady.

    All the gaskets are remade and glued on.  In the case of the removable cover frame, it is gasketed with soft, thick deerskin, to give a very compliant seal. since the cover assembly is fixed in place with flat hooks instead of screws.  The gaskets inside, which seal the sliding glass door, are the same material.  Since it would be difficult to trim the gaskets along the edges after gluing, and keep a neat, straight line along the exposed edges at the edge and the window frame, these packings are accurately cot to width and carefully glued against the edge, working a little at a time.

    The joints that make up the five sides of the spoolbox itself were pouch leather.  The panels forming the box are very accurately cut, so they fit together tightly even with such thin packing.   To insure good tracking of the roll, the spoolbox structure must be fitted together exactly as originally made, so pouch leather was used again for these gaskets.  A rubbing was made using paper made sticky with Spray Mount and a soft pencil.  Since it is hard to butt join such thin leather, the back panel gasket was made in one piece.  Not as uneconomical as it seems, as the two C shaped gaskets can be "interlocked" on the piece, leaving a square in the middle from which all the other gaskets were cut.

    First the top and bottom; then the two back panels, and finally the extension board at the left, are assembled.  Two little gasketed wooden cubes are fitted between the back panels, to complete the outline against which the tracker bar assembly is gasketed.  Afterwards, the edges of the pouch leather gaskets that show inside the box, were blackened with a very fine felt pen.  The hinge bar that holds the tracker bar flip cover, won't come apart, so it has to be put in while the box is being assembled.  There is no bushing or packing around the hole where this rod emerges from the box at the right; only a close fitting hole.  This hole was smeared with Dow-111 to make a seal around the rod.  A punching of thin green action cloth, darkened with a marker, goes around the ends of the rod, to keep it centered, so the arms will not scratch the sides of the box.

    The tracker bar was cleaned with lacquer thinner to get off any remnant of old lacquer; Naval Jelly to remove the bulk of the corrosion, and then lightly polished with Brasso, and rinsed again with thinner.  It was lacquered with metal lacquer thinned 2/1, wiped on with a cloth.  Lacquer interferes with the smooth running of the music roll, but such a thin coat is soon rubbed off the active part of the bar, leaving the ends still shiny.  The inner part of the circuit was retubed.  I discovered that the tracker bar, the old type made from thin sheet metal with the nipples squared and soldered right through to the face, actually deflects at the center under the combined tension of 58 rubber tubes put in tight.  So each tube was left with a slight bow, to keep them slack.  A deerskin gasket (not shown) was made for where this assembly flanges up to the rear of the spoolbox.

    The upper chamber of the spoolbox had no clack plate, but the area where the rerolling D-ring smacked the wood was severely eroded.  So, following Aeolian's later practice in pipe organs, wine colored velvet was glued to thin pressboard and cut into 1-1/2" strips.  These strips were cut to length and stuck in place with Spray Mount (completely reversible).

    The left hand extension board, and the tracker assembly, was attached to the box.  All the screws that show inside the box came from my collection of nickel plated oval headed wood screws, with their heads (perhaps futilely) lacquered with clear nail polish.  The complete box was then attached to the back board.  The four screws that hold it on were stripped out, because the heavy box had not been properly supported at one time.  I found some old 3-1/2" #10 screws that went way in, and fixed that.  Tubing the tracker bar back flange to the tee bar proved to be a challenge.  There is not much room for the bends, which have to be clear of the primary valve box.  The modern tubing from Player Piano Co.  apparently kinks easier than the original, thick walled cloth covered tubing that was used.  After much trial and error (and wasted tubing), this method seems to work.  Starting at the center, the middle tubes with straight nipples on the tee bar can be put in in the regular manner.  For the majority of the tubes that connect to the tee bar with 45 elbows, I tried to keep the pile of tube bends only four rows deep.  The first step (this picture did not come out) is to connect every fourth tube (every second tube on the lower row of staggered nipples at the top) and mold the bends into a single, concentric layer.  A pile of front rail punchings screwed on, forms a sort of capstan, to keep the smallest bend from popping into a kink.  Then make a second layer out of tubes 3, 7, etc., and a third layer from tubes 2, 6, etc. (every other nipple in the upper top layer).

    Then make the final layer from the remaining tubes.

    The primary pouch board is attached to the top of the tee bar.  A deerskin gasket is made, and punched using a rubbing made with a strip of making tape.  Following Aeolian's practice for this type of joint, #6 organ chest springs (O. S. I. item #7800.06) were used on the screws

    The spoolbox and backboard was temporarily installed on the organ, with two wooden angle brackets.  Until the case comes back from the refinisher, I don't know exactly where it will finally go.  At that time, new permanent support bars will be made.

    To test the system as done so far, the tee bar is temporarily tubed to the manual valve box.  First the manual valves are debugged as described in Chapter 14.4.  Once all the keys reliably switch wind to the primary circuit only when pushed, the rest of the primary circuit is tested.  First a tube is plugged into the place where the touchbox tube normally goes, and that circuit is tested by blowing.  One can easily detect with the tongue, the movement of the pouch when blown, and the air can be felt coming out of the tracker bar.  Three of the pouches wouldn't blow; I had forgotten to poke out the glue bubble that sometimes forms when a closely punched "channel" gasket (for the primary pouch board attachment) is put on.  After that was fixed, the test continued using the organ's wind.  When the tracker bar was covered with the flipper (see chapter 15.2), pushing a key would make the primary pouch lift two nickels. With the tracker bar open, the wind can be felt coming out of the tracker bar port, and the primary pouch will lift only one nickel.  The pouches fell back too slowly when the key is released, but that is explained by the fact that new bleeds with tiny holes were used on the new primary pouch board.  I know that 6/inch bleeds are much larger, but I don't know the exact size.  This can be easily fixed later, when the instrument is complete and tested with my new test roll from Kevin McElhone, which includes trills in each note for this purpose

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