Cleaning the keyboard contacts on a Schober Recital organ

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Cleaning keyboards

Adding connectors

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Pedalboard

Specification

Preparation

The gold-plated springs and bus bars in Schober (Pratt-Reed) keyboards weren't supposed to need cleaning, but after thirty some years most of them do.  Originally the wires from the keyboards were soldered directly to terminal points at locations H through W on the terminal board,  but I strongly recommend adding connectors.  This will facilitate temporarily re-installing the keyboards for testing and then removing them if necessary for further cleaning.   Otherwise you may end up unsoldering and resoldering the keyboards wiring many times.

After reading through the procedure below, the next thing to do is to order the supplies, which typically take a week or so to arrive.  Find some area which is secure and free of cats, and set up a table for working on the keyboards.  Provide a towel or other soft surface so the keyboards can be turned over without scratching the key tops.

Removing the keyboards

	Removing the keyboards is fairly straightforward.  First remove the trim boards under the keyboards, each of which is secured with four brass screws.  Set these aside in a safe place until it's time to re-assemble the organ.  Then carefully lift the nameboard, and insert a spacer of some kind on either side of the Swell keyboard (in the photograph, the spacers were two rolls of electrical tape).  From the back of the organ, unsolder the keyboard wires from the terminal board.  Remove the screws which hold the Great keyboard to the key shelf.  To remove the keyboard, lift it only by parts that are made of steel.  Be sure not to touch or damage any of the contact springs underneath the keyboard or exposed at the bass end.  I usually place one hand at the front center under the the keys,  against the frame and touching the steel key stops, and the other at the back center grasping the steel tails of the keys.  The hand at front center carries most of the weight of the keyboard, so try to avoid putting force on the plastic key tops.  It may be easier for two people to lift the keyboard, one near the bass end and one near the treble end, but always lifting by steel parts at the front and back. Carefully slide and lift the Great keyboard out and place it on the table with the keys on top.  Collect the screws and washers in a glass jar so they won't get lost. When the keyboards are out of the console the exposed gold springs at the bass end are especially vulnerable, so always lift the keyboards by the steel parts at the front and back.
	Once the Great keyboard is safely removed, it's easy to remove the Swell keyboard in a similar way.  Remove the screws from under the key shelf of the console, then grasp the key tops to gently pull the keyboard toward you until there is plenty of room to reach behind it for lifting.  Lift the Swell keyboard in the same way as the Great keyboard, and place it on the table with the keys on the bottom and the metal brackets facing upward.  Remove the metal brackets, noting how the overhangs are positioned at top front, and set them aside.  Gather the screws, washers, and nuts into a glass jar.  Now you are ready to clean the Swell keyboard.

Cleaning the contacts

I cleaned all the gold spring contacts in the keyboards, pedalboard, and stop assemblies using DeoxIT cleaner, followed by DeoxIT Gold (formerly ProGold).  I'll describe the procedure for the keyboards, but it is similar for the stop switchs, couplers, and pedalboard contacts.  Except for the keyboards, it's not necessary to remove any of these from the organ in order to clean them.  The coupler switches are relative inaccessible, but you can apply a drop of cleaner to the tip of a knitting needle or awl, then transfer the drop to the a contact point.  A bit tedious, but probably better than removing the stop assemblies.  An alternative is to buy a small can of DeoxIT spray just for the coupler switches.

	It's not necessary to clean the entire length of the gold springs, but only the area where they make contact with the gold busses. This can usually be accomplished by depositing one drop of the DeoxIT cleaner at the contact point with the contacts closed, then operating the key a number of times. The DeoxIT cleaner has a penetrating effect, and within hours or at most a few days it spreads along the entire length of the springs anyway.  In fact, you will see red dots of solvent (picture at left) surrounding the springs on the clear plastic switch arms.  Don't be alarmed, the solvent appears to be compatible with the plastic.  But if one or more dots don't appear after a few days, check to make sure you treated those particular springs.
	If the contact springs are heavily oxidized, you may not see much if any glimmer of gold at first. On my Swell keyboard, it seems that copper has migrated through the gold layer and oxidized. Initially it appeared that DeoxIT wasn't penetrating this layer, but after two treatments one week apart, gold began to show through. Don't worry if some parts of the gold springs or busses still look oxidized -- what counts is how clean they are in the small area where contact is made, and how well they work.
	After cleaning, plug (or solder) in the keyboard and try it. If there are a few problem notes, try just playing the organ for a few days then checking again. Be sure to play in enough different keys so that you use all the notes! Also, use the 16 foot stops or coupler some of the time and play an octave higher so that you exercise the top octave. Play some chromatic scales to make sure you hit everything. If you still have a lot of bad notes after a few days of use, remove the keyboard and clean all the contacts again. If there are just a few bad notes, make a list and concentrate on those. Don't apply DeoxIT Gold until you are happy with the results; the cleaner is to get the contacts working, and DeoxIT Gold is to keep them working.
	If there are problem notes that don't respond to two applications of DeoxIT cleaner, strips of lint-free cotton cloth (available from Caig) can be used to lightly buff the contact area. I generally cut these to about 3/8" or 1/4" width, then gently pull them through the contact area with the contacts lightly closed. It may be necessary to apply more DeoxIT cleaner and to do this several times. If desired, more oxide can be removed from the non-contact surface of the gold busses by wetting the tip of a cotton swab with DeoxIT cleaner, then rubbing it along the busses.  Be much more cautious about cleaning the non-contact areas of the gold springs.  If you attempt it at all, be sure to use lint-free swabs and to apply almost no pressure.
	When you are ready to apply DeoxIT Gold, start by applying a single drop at the contact point with the contacts closed.  As with the cleaner, the contact treatment will spread along the springs of its own accord.  If desired, you can use a cotton swab to apply a thin layer of DexoIT Gold to the non-contact areas of the gold busses.

Other stuff to clean while you are at it

While the keyboards are out is a good time to vacuum all the dust out of the console.  Use care when cleaning the pedalboard switches.

Since you have the supplies, this is also a good time to clean the wafer switches that control Pedal Volume, Vibrato Depth, and so on.  Apply a drop of cleaner at each switch contact location, then rotate the switch a few times.  Spread cleaner over the silver-plated surfaces with a lint-free swab. Let the cleaner sit on the switches overnight, then user fresh lint-free swabs moistened lightly with cleaner to remove the oxide.  Finally, apply DeoxIT Gold to the silver-plated surfaces.

Clean the edge connectors on each stop filter card by applying two or three drops of cleaner, then rubbing with a piece of lint-free cloth.  When the oxidation is gone, treat with DeoxIT Gold in the same way and plug the card back in.

Supplies

DeoxIT contact cleaner and DeoxIT Gold (formerly ProGold) contact treatment are available from Caig Laboratories.  The 25cc needle dispenser bottles (DeoxIT D100L-25 and DeoxIT Gold G100L-25) are the most convenient and economical for working on Schober (or other Pratt-Reed) keyboards and stop switches.  One bottle of each will normally be enough to clean and treat all the gold spring contacts in a Schober organ many times.  Despite the name, DeoxIT Gold can also be used on silver contacts such as wafer switches and DIN connectors.

Qty	Part number	Description	Comment
1	D100L-25	DeoxIT 25cc needle dispenser	Contact cleaner
1	G100L-25	DeoxIT Gold 25cc needle dispenser	Contact treatment
1	K-AS10	Accessory Sampler kit (swabs, lint-free cloth, etc.)

You will need lint-free cotton cloth and small lint-free swabs.  The K-AS10 Accessory Sampler Kit contains enough lint-free cloth and some useful swabs and brushes.  You will probably need more lint-free swabs than provided in the kit, though ordinary good-quality cotton swabs can be used for cleaning gold busses (but not the gold springs!).

Last updated April 25, 2007