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
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