Dean Moore's Question on Valve Blocks
By Les Smith
Hi, Dean. When you actually get to rebuilding those Amphion valve blocks on your Ampico stack, let me know how many extras you need and I'll be pleased to supply you with however many you need. The problem with the valve blocks is rarely with the valve itself, but rather usually with the pouch, or more correctly the lifter disc. For some reason Amphion used an extremely thick lifter disc. Over the years, as the leather pouches lose some of their dish, the thick lifter disc prevents the valve from properly seating, creating a problem. The only way to correct it is by replacing the pouch and to do that you have to break open the valve block. BTW, when I replace the pouches I DON'T reuse the original lifter discs, I use new, slightly thinner ones. I would like to congratulate you on even THINKING about rebuilding the valve blocks. In 99% of the Ampicos and Amphions that I see the valve blocks are never opened up to replace the pouches and lifter discs, which is why most regular players that utilize an Amphion stack, even after they've been "rebuilt", won't work with the foot pumps and almost invariably have been "electrified". Like-wise,the valve-blocks are just as infrequently rebuilt even on Ampico grands, so it's not uncommon to find their electric motors out-fitted with pulleys the size of saucers! With some of those Ampico grands out-fitted with over-sized pulleys, it's tough to decide whether the piano's going to "hula" itself right off it's legs and crash to the floor, or lift off the floor and start heading for the ceiling because of air turbulence! Sanding all the finish off the valve blocks will reveal the glued joints that have to broken apart. Another technique is to place the valve blocks, a few at a time, in either a conventional or microwave oven, in order to soften the glue, so that they can be disassembled. If you choose this latter technique, MAKE SURE that you remove the top seat and valve first! Anyway, if you do inadvertently trash some valve blocks in the disassembly process, let me know how many you need. Good luck!
Les Smith
lessmith@buffnet.net |
(Message sent Thu 7 Mar 1996, 20:56:05 GMT, from time zone GMT-0500.) |
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