[pianotech] Balance rail bushings

[Scott Helms, RPT]

I like to use a 50/50 mix of water and DIF wallpaper remover (available at
paint and home improvement stores). Soak the old bushings for about 20-30
min with this stuff, and usually they pull right out very cleanly with
tweezers (sometimes they just fall out on their own!) Make sure to let the
keys dry completely (I wait overnight at least) before rebushing them.

Scott
------
Scott A. Helms, Registered Piano Technician
480-818-3871
www.helmsmusic.net






> Matthew,
>
> One thing I discovered when I started replacing keybushings back in the
> 90's, was that it was easy to have them come out too loose. I like a firm
> balance rail bushing with only a few thousands of play. If you use
> standard
> 146 cauls and leave them in to dry, your balance rail bushings will be too
> loose.
>
> Nobody ever told me this when I was starting out!
>
> Bill Spurlock sells a set of balance rail cauls that are not oversized
> like
> the standard ones. These will leave the bushings a little tighter. Even
> so,
> I pull the cauls out after about 15 minutes to allow the bushings to
> expand
> slightly. This seems to get them very close to where I like them.
>
> Also I prefer the balance rail bushings to have ears. Others prefer to
> have
> them cut flush with the top of the key, but I see no advantage to this. By
> stretching the felt over the top of the key, I believe it puts a little
> tension in the felt which I feel is beneficial. Additionally, the ears sit
> up about a millimeter or so above the surface of the keybutton - this
> gives
> slightly more support - again, another advantage from my viewpoint.
>
> If anyone knows of a functional advantage of having the cloth cut flush,
> I'd
> like to know what it is.
>
> Of course, *hot hide glue is the correct glue to use.* It gels on the
> surface of the felt, leaving it more resilient, and it is easier to
> replace
> the bushings in the future.
>
> For getting old bushings out, I find it is best to soak them first before
> using the steam. Formula 409 seems to work the best! I mix it with 50
> percent water. I use small wedges cut from hammer scraps that are small
> enough to fit into the mortises. These get soaked in the solution and
> inserted into the keys.
>
> If you leave them overnight they may dry out, so it is best to cover them
> with plastic wrap. In the morning you will find that they will usually
> almost fall out with no steam needed. Sometimes a little steam will still
> facilitate removal.
>
>
> On Sat, Jul 11, 2009 at 3:00 PM, Matthew Todd
> <toddpianoworks at att.net>wrote:
>
>> I will be doing a balance rail bushing job soon, and just wanted to see
>> how
>> replacing the balance rail differs from replacing the front rail, i.e.,
>> the
>> key buttons.  I am assuming I can take off the old ones using steam.
>> And
>> then, what would be the best cauls to purchase.
>>
>> Thank you for the advice,
>>
>> ***TODD PIANO WORKS*
>> Matthew Todd, Piano Technician
>> (979) 248-9578
>> http://www.toddpianoworks.com
>>
>
>
>
> --
> Ryan Sowers, RPT
> Puget Sound Chapter
> Olympia, WA
> www.pianova.net
>