Changer adjustment

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Bill Atwood
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Changer adjustment

Post by Bill Atwood »

I am about to begin assembly of a newly refurbished 1984 Sierra 12-U. I need help with the adjustment of the return springs on the bottom of the changer. Can anyone tell me the proper proceedure? Prior to disassembly, I took pictures so I can get close. I would like to get it right!
Thanks
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Larry Bell
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Post by Larry Bell »

The purpose of return springs is to bring a lowered note back up to pitch and to hold the lower finger against the stop while the string is being raised. When adjusted too tight, the action will become stiff. When too loose, it won't return from a lower properly or won't raise completely without the lower finger pulling off the stop and limiting the raise. Raises don't need return springs, since string tension returns them pretty well, but both raises and lowers need to be examined re: the return springs.

To adjust:
For each string, activate the pedal or lever that lowers that string the most. Check to be sure it comes back to pitch when released. If not, tighten it. If it does, loosen the spring until it just brings the string back to pitch and then 1/2 turn more to allow for stretching. NOW YOU'RE HALF DONE. For each string, activate the pedal or lever that raises the string the most. Be sure the spring holds the lower finger firmly against the stop while the raise occurs. If so, you're done. If not, tighten it until the lower finger stays put while raising.

That should do it. I'm not sure whether the Sierra has adjustable springs. If it does, turning the adjustment screw on the endplate will vary the tension. Otherwise, you have to cut the spring to tighten or stretch the spring slightly to loosen (PITA). Lets hear it for adjustable return springs. Image

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<small>Larry Bell - email: larry@larrybell.org - gigs - Home Page
2003 Fessenden S/D-12 8x8, 1969 Emmons S-12 6x6, 1971 Dobro, Standel and Peavey Amps
C Dixon
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Post by C Dixon »

Excellent advice Larry,

carl
Bill Atwood
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Post by Bill Atwood »

Thanks Larry
It does have adjustable springs and your advice is quite clear. I should be able to get back up and playing. I've always wanted a lacquer finish on some beautiful wood. I replaced perfectly good laminate with a nice walnut burl veneer. If I can stay patient with the finish, it's going to be a beautiful one of a kind!
Thanks again.