Replacement Switches for Pianos
By Robbie Rhodes
I spoke today with saleslady Evelyn at Electric Switches, Inc., in Los Angeles, tel 213-660-1310, and I described the push-pull switch action needed for the Ampico and other pianos. She agreed that Arrow Hart Co. (now owned by Cutler-Hammer div. of Cooper Industries), might have made the original switches in the 1920's, and that she recalled seeing something similar recently.
She mused, "I'm looking right now at four feet of catalogs on the shelves, and I have no idea right now where I saw it. "Evelyn suggested that I phone her next week and hope her memory has revived!
The larger electronic parts catalogs, such as published by Allied and Newark, have illustrations of the common Arrow Hart switches. Style 81084-G is rated at 6 amperes 125 vac, and is a quick-make/quick-break action suitable for piano motors. The internal spring inside the metal push-button shaft makes the switch a "momentary" action; however, an external compression spring pushing on the button would oppose the internal spring, yielding the desired push-pull action. I think a long control rod could safely be brazed to the top of the steel push-button.
My guess is that the original push-pull style switch we are seeking is simply the 81084-G, or similar, without the internal spring which pushes the button out. I hope Evelyn can remember. (She remembers player pianos!)
The rotary switch used in the Ampico B is still listed: style 1561BS, and Arrow Hart still makes several old-style toggle switches with a solid brass bat-handle which could be drilled to accept a linkage pin. I ordered a catalog which gives dimensions of the more popular designs.
Incidentally, the Metal-Oxide-Varistor (MOV) device used in most surge suppression devices for computers is available in sizes suitable for suppressing the arc at motor switches. Has anyone tried this?
-- Robbie Rhodes
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(Message sent Sat 17 Aug 1996, 02:32:48 GMT, from time zone GMT-0700.) |
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