[CAUT] Damper wire alignment (was:Underlever Felt)

David Ilvedson ilvey at sbcglobal.net
Mon Aug 24 20:22:59 MDT 2009


Well, that is a pretty cool idea.   I will give it a try...

David Ilvedson, RPT
Pacifica, CA  94044

----- Original message ----------------------------------------
From: "Jon Page" <jonpage at comcast.net>
To: caut at ptg.org
Received: 8/24/2009 6:30:19 PM
Subject: Re: [CAUT] Damper wire alignment (was:Underlever Felt)


>>I still have a problem determining which way and how to bend the 
>>wire for fit in the top flange...do you see something in particular 
>>that tells you I need to bend the wire towards the bass?   The first 
>>bend is above the top flange?

>With the wire perpendicular to the guide rail and the head centered
>over the unison, the unsecured top flange should be free to move
>on the wire. I'm assuming the guide rail is parallel to the string plane.

>One way to visualize the offset is to make a few tools.
>One wire is suspended from the strings perpendicularly.
>The other wire is inserted in the top flange.

>This gives you the offset and the angle at which the
>wire needs to enter the top flange. If you hold the damper wire
>with a square against the guide rail and a sample wire
>in the top flange, it does the same thing.

>Many times I find it necessary to ream the top flange hole
>.003 to .005" larger than the wire to insure easier assembly.

>I also try to make the wire offsets parallel to the damper head,
>at least the top section.  I use my 90 degree damper wire bender
>for combination handle to sight this and it is also is scored
>at two points for indexing the bends.

>First, place the wire in the guide rail and square it off.
>Center the head over the unison: remove the damper and make
>the appropriate bends at the head; check that the head is parallel
>to the top section of wire by holding the bending tool against the head.
>Reinsert the wire in the bushing, square it off and recheck the damper
>head alignment over the unison. This may take a few readjustments.

>With the wire braced perpendicularly to the rail, ascertain the offset
>and angle of the bottom section to the top flange hole alignment wire.
>Correct the bends to allow the top wire section to remain perpendicular
>to the rail while the lower section inserts freely into the top flange.

>Secure the set screw. The damper should travel straight up and down
>without drag.

>The other school of thought is to have the wire pressing into the
>guide rail bushing. This may save time on installation and assist
>damping by bracing the wire but I see it as unnecessary friction
>because frictionless damper motion dampens as well (if not better).

>I don't want to make the damper wire up tight,
>I like it free and easy. Friction is like a real  drag.
>-- 

>Regards,

>Jon Page



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