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Additions




The Apollo Organ is important for several reasons; this particular instrument was one of the last built by Rushworths and it is in near to original condition. But more importantly it is used as a practice organ every day and must therefore be kept in perfect regulation. In 2004 a Swell to Great reversible pedal was added which simply draws the Swell to Great stop on depression, and takes the stop back in on pressing it again. Plans for the action were kindly supplied by Messrs Harrison & Harrison, Organ builders of Durham. The pedal was installed at the extreme left of the pedalboard where a section of casework could be unscrewed and a pedal accepted, this was neccesary so that none of the case was altered and can be put back at any time.

More recently, a system of pneumatic thumb pistons has been installed undernieth the great manual. These (will) act on the Great to Pedal coupler; the Swell to Great coupler; and two other stops (as yet, not decided).

At the moment, simply the primary action is in place (thumb pistons and pallet valves), which will soon be tubed to a pouch box fed with suction from the main bellows. The pouches will direct suction to the correct pneumatic motors which will collapse and draw one stop each.

Photographs of the thumb pistons are shown below:





The Organ with both manuals removed, the pistons have been temporarily installed so as measurements can be taken.
Thumb pistons





The 4 pistons installed and the brass rods which they actuate are cut to the correct size so that the pistons all sit the same distance from the keyslip.
Thumb pistons





The keys are re-installed into the keyframe. The 4 holes visable in the photograph are ready to accept lead (or other suitable material) tubing. When a piston is pushed, a felt-covered round pallet valve is opened, this admits atmosphere to the end of the tube. This signal is sent to the puch box where it comunicates with a valve which allows suction to feed to the correct motor pneumatic which will draw the stop associated with that particular piston.
Thumb pistons





The 'finished' installation. At this point, the pistons do not have any effect on the organ, further details will be added when the system is complete.
Thumb pistons





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