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403 South Jefferson Ave.
Saginaw, MI 48607



Wednesday, November 14, 2012

Photo Summary, Nov. 14 - Organ Project

A summary of organ project benchmarks is documented photographically with captions provided courtesy of technician Joe Granger of Scott Smith Pipe Organs.

1. The Chamade in the process of being removed for shipment to Maryland for revoicing, including new tongues and shallots for transformation into Solo Tuba. These pipes will be the only pipework from the 1965 rebuild to be incorporated into the finished instrument. The surprisingly large scale of the pipes allows for successful revoicing into a true solo stop of Skinner tone that will be heard over the top of the full organ.
2. The Choir regulator removed from chamber. Regulators allow the air pressure to remain constant and steady, essentially a lung that never runs out of air. There will be a total of nine regulators when the organ is completed.

3. Choir regulator in process of teardown, removing old leather and rubbercloth.

4. Choir regulator with new spring arm to replace the one removed in the 1965 rebuild to lower the pressure. New spring arms of maple to original specifications will bring pressure of Choir back to factory spec and allow the pipework to speak and sound as they did in 1928.

5. Releathered Choir regulator, completed and ready for reinstallation.

6. The original cone valve gasket inside the choir regulator keeps the pressure constant; note the coal dust accumulation from the past 80 years, from the coal fired power plants.

7. Underneath the cone valve gasket shows molded felt, which forms a tight seal around the cone valve.

8. New leather, which has been skivved (a process of shaving down the edges of leather using a beveled razor blade to form air tight seal when glued), formed around the felt donut, and reapplied with hide glue. Creating a cone valve gasket is one of the more labor-intensive and difficult processes when restoring a Skinner regulator, for the leather has to be cut very precisely, skivved on all four sides, stretched, glued, heated and tacked to ensure a proper seal around the cone valve.

9. New blow strips of leather are applied over the glued and doweled joints in the bed of the regulator to assure air tightness and no leaks.

10. The completed cone valve gasket and blow strips.

11. The French Horn from Skinner Op. 748, 1927. These imitative pipes, when restored, will be added to the Choir division; these are some of the most desirable Skinner pipes ever created

12. Removing the Choir mechanism, including stop action, pouch boards, and primary pneumatics from underneath the chests.

13. A pouchboard. The valve style here isn't actually the Skinner style and was done by the regional Casavant representative in 1965. These valves will be replaced with Skinner-style valves that do not have huge felt pads (so the diaphragm, itself, tents a little higher). Note: the top is missing pouches where the super-octave was, which will also be replaced. The white leather top actually seals off the air from the bottom of the pipe and when activated, these pouches deflate and allow the air in the chest to flow into the toe of the pipe causing the pipe to sound.

14. The pitman rail. Note that the super octave is filled in with dowels. The paper packing of the pouchboard was also left unpunched. These will be drilled out to accommodate upperwork.

15. The primary pouches for the Dulciana borrow action. These are still original and not in too bad shape either. Even at over eighty years old, this leather was in far better condition than the leather used in the 1965 rebuild due to a key chemical process used in tanning of leather (Chromium) that was taken out of process in the late 50s. The new leather that will replace this will be tanned using the same process as the original leather, extending its life to up to eighty years. The leather from the 50s-70s has a life of about thirty-five years.

16. Two pouches off a pouchboard. The dowel on the back is meant to hold the spring secure. The springs are correct, but Skinner pouches have a second disk with a hole in the center for the spring to fit inside which will be recreated to Skinner specifications.

17. The Choir pouchboards cleaned off and ready for new leather pouches.

18. Choir pouchboards with springs in place for new pouches. These springs counteract the air pressure.  When deactivated, the pouches spring back to a closed position extremely quickly and cut off the air supply to the pipe above.

19. A completed pouchboard. There are over forty-eight of these boards in this organ, an extremely labor intensive process that takes steady hands and patience.

20. The Choir stop action torn down and ready for new gaskets and pouches. This device activates the nine ranks of pipes within the Choir division. Each division has its own stop action.

21. Replacing the old pouches on the stop action of the Choir division.

22. Replacing the old pillow gasket on the stop action – one of the more difficult and skillful processes of restoring a Skinner action.

23. The newly completed pillow gasket will ensure an air tight seal.

24. The high-pressure Tuba and French Horn regulator under the Choir division. As in the Choir regulator, the spring arms and some of the springs have been removed in the 1965 rebuild to lower the pressure.

25. Newly fabricated spring arm of maple. Luckily, during the 1965 rebuild, one of these arms was left in place, allowing technicians to create an identical arm.

26. New leather blow strips for the tuba regulator will ensure air cannot seep through the joints in the wood.

27. Completed cone valve gasket for the Tuba regulator.

28. The completed Tuba regulator will create 10” of pressure and will not only supply air for the existing Tuba, but also power the soon-to-be-installed French Horn, also on 10” of pressure, helped by the new spring arms visible in the middle of the regulator.

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