On Mar 13, 2009, at 1:41 PM, Porritt, David wrote: > OK, what’s the theory here? When knuckles need to be bolstered or > the leather tightened – what was the cause? Did the core felt get > too packed, or did the leather stretch? If the leather stretched, > the bolstered knuckle will be larger changing the action ratio > some. If the felt packed down and you make the leather shorter the > knuckle will be smaller and also change the action ratio. Since in > many cases we didn’t see the knuckles when new and even if we did > there’s probably zero chance that we’ll remember how large the > knuckles were originally. Which repair would keep the action ratio > the same? If you have the time and money to worry about action ratio, you can replace parts. If you have an old action where either the leather has stretched and become sloppy, or the core felt has compacted, leaving the leather sloppy, you can improve the feel and response of the action by tightening the leather. Bolstering, to my mind, is not as good a way to go, as it misshapes the knuckle - and it's a pain in the butt to do. If the action is worn enough that the cause is compacted felt, there are no doubt other issues that would be dealt with in an ideal scenario. But stretching will improve things, regardless. The tiny difference in knuckle diameter will have a small effect compared to the impact of tight vs sloppy leather. That's my take, at any rate. Regards, Fred Sturm University of New Mexico fssturm at unm.edu -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/caut_ptg.org/attachments/20090313/bd4a0a91/attachment-0001.html>
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