Jon, You have given somethings to think about. Thank you. The sorting by knuckle height, do you think a player feels any uneveness if this is not done, or is this mainly the elegance of straightlines? Something BTW that I am all in favor of but had not considered. THanks, Chris Solliday ----- Original Message ----- From: "Jon Page" <jonpage at comcast.net> To: <caut at ptg.org> Sent: Friday, February 15, 2008 10:05 AM Subject: [CAUT] hammer line > I weigh shanks and separate them into piles to the .1 g. > Then I measure the height of the knuckle, measuring > the shank too (the shank width variance is negligible) > but the knuckles are not always pressed in the same. > So I further break down each weight pile into three groups: > low, med, hi. I try to keep the variance within .010" (.25mm) > and set aside ones out of the 'window'. > > I weigh the bored/tapered heads and plot their weights on a chart. > > According to the hammer weight, I'll select the appropriate weight shank > to achieve as smooth of a SW curve as possible bearing in mind knuckle > height groupings to place the med's more central and the low's and hi's at > the extremes, screwing the shanks to the rail as I go. > > Grouping like-height knuckles leaves a more even let off button line and > one less variable with note to note wippen/shank vertical placement > (I know there's a better word for this). > > By assigning a specific weight shank to a hammer weight less SW adjustment > is needed at the end of the process, ie; if the hi bass weighs 9.5 and the low > tenor weighs 9, using the same weight shanks will leave the .5 g difference. > But if you place a 1.7 g shank with the bass hammer and a 2g shank > with the tenor you will come out with 11.2 and 11, respectively. Depending > on the availability of sizes, you can strive for the same weight or a > .1g difference. > > I then install the hammers and let dry, then remove them from the rail. > Next is to cut the shank protrusion off with a band saw and rough cut the arc. > Cut all tails to a even length ( I order longer moldings to accommodate a > tapered bore) and sand the tails to a 3" arc. This produces a nice > finished edge. > Arcing removes about .3g. > > Now comes the final weigh off. Usually only 12 to 18 need addressing. > I precut the hammer leads so I only need to look at the graph to install the > appropriate lead. If material needs to be removed. I'll first look at > the front side > of the cove to remove a few tenths with a Forstner bit. I order sets uncoved > as well; so as not to be hindered in the arcing process with a deep cove. The > cove removes so little weight, it is not worth the effort in the > scheme of things. > > FInally, easing the rear edges and bottom of the tail with a file. Reinstall. > -- > > Regards, > > Jon Page
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