[pianotech] Knuckles Replacement - the details

[Joseph Garrett]

No. That's the short answer. Occasionally, a little "slice" if there is a
large glue glob at the base of the knuckle. However, the "slightly
modified" fence wire cutters take care of most of that.
joe


> [Original Message]
> From: David Weiss <davidweiss at embarqmail.com>
> To: <joegarrett at earthlink.net>; <pianotech at ptg.org>
> Date: 2/6/2012 3:10:04 AM
> Subject: RE: [pianotech] Knuckles Replacement - the details
>
> Joe,
>
> Thanks for the details.  Before you remove the knuckles with the fence
wire
> cutting pliers do you get them loose with heat or wallpaper remover or
some
> other method?
>
> Thanks,
>
> David Weiss
>
> PS.  Any chance we could see a photo of the modified fence wire cutting
> pliers?
>
> -----Original Message-----
> From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On
Behalf
> Of Joseph Garrett
> Sent: Sunday, February 05, 2012 9:51 PM
> To: pianotech
> Subject: Re: [pianotech] Knuckles Replacement - the details
>
> Just finished swapping out the 10mm knuckles for some 9mm ones. As I was
> doing it, it occurred to me that the fine details might be of use to those
> who have not done this job. So, here they are:
> I removed the original knuckles with Fence Wire Cutting Pliers(slightly
> modified<G>).  As I did, I cleaned the notches and removed any residual
glue
> from the shanks & mortises. I did this with Nicholson 4" files, one with
the
> sides made "safe", the other left as is. It turned out that the "as is"
one
> was .001" thinner than the "safe" one, which was used as the final thing
to
> clean out the mortise and size it. The "as is " one was exactly the
> dimension of the mortise. <G> Once all the shanks were prepped, then each
> individual knuckle was fitted for it's shank mortise and the nap of the
> leather was determined. The nap needs to be smooth towards the end of the
> shank and rough towards the centerpin. The "rosewood" of the knuckles is
not
> absolutely the same size, nor are the mortises of the shanks, so
individual
> "fitting" is needed. Once the knuckle was "fitted", it was then glued into
> the mortise. I use modified clothes pins, (the spring type), to add just
> enough pressure to hold the knuckle at right angles to the shank and in
the
> bottom of the mortise, without crushing the knuckle. At the same time as
the
> gluing process, I double check for damage from the removal of the other
> knuckles. If found, I press glue into the
> crack(s) and the clamping does a double duty. I have 16 of the clamps, so
I
> just pull from the first of the shanks, when I get to #16 I use #1. It
seems
> that the cold hide glue has set up sufficiently in this amount of time.
The
> work goes fairly quickly, even though I'm doing a bunch of things to each
> one of the shanks, in the process. Once the glue is set, I clean up any
glue
> beads/smears on the outside of the joint(s). Of course, in the process, I
> make sure the knuckles are in exactly the proper position in relation to
the
> shank/motises.
> Hope that helps.
> Joe
>
>
> Joe Garrett, R.P.T.
> Captain of the Tool Police
> Squares R I
>