Action Geometry Consistency

[Richard Brekne]

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"Bradley M. Snook" wrote:

> RicB: "Yes, you should. And its no big deal to do so really. A good
> set of pinchers applied neatly at the knuckle core and you can pop
> them right out. Just make sure you keep track of which way the nap of
> the leather is going. Reglue carefully to line up better then you
> started out with. You see this all the time, and out of place or angle
> knuckles can really affect the ratio big time. Improving this kind of
> thing not only can help drastically the problem you mention, but also
> make for much more consistent leverage and play." OK, this kind of
> thing is what I was really after . . I'll give this a try sometime
> today. One thing though: I should probably line up the flange side of
> the knuckle (instead of the hammer side), is that right?
> What you want to do is to just make sure the all the knuckles are at
> exactomundo 90 degrees (as in perpendicular :) ) to the shank, and
> that they are not cockeyed so that one side is higher then the other.
> If the slots for the knuckle cores are not in the same place...well
> then you have a bit more work to do, but thats not usually the case.
> Just make them all nice and straight.
>
> So it doesnt matter which side you line up so much... all the sides
> have to line up...sort of like looking down a nice clean hammer line.
>  Richard, you had also talked about looking at the wippen height. Have
> you every bolstered the knuckles to compensate for the unevenness in
> the wippen height?
>
> I have bolstered knuckles on occasion, but only to compensate for very
> flatened knuckles that had plenty of good leather on them. Been a
> while now as I usually just replace them.  In anycase I dont think I'd
> look at it exactly as compensating for uneveness in whippen height....
> tho I see where you are coming from.
>
> Uneven whippen height normally relfects something about the hammer
> line. Either hammer bore is irratic, or knuckles are inconsistant...
> there are other possibilities. A good test is to put a straight edge
> under a whole section of whippen cushions with the rack off of the
> keyframe. This insures a dead on whippen line for the moment... then
> look at your hammer line and note any inconsistancies. Gives you a
> real good picture of some of the problem areas you have in your top
> action. Correct what you can of course :)
>
> Hope this helps.
>
>  Bradley

Cheers
RicB
--
Richard Brekne
RPT, N.P.T.F.
UiB, Bergen, Norway
mailto:rbrekne@broadpark.no
http://home.broadpark.no/~rbrekne/ricmain.html
http://www.hf.uib.no/grieg/personer/cv_RB.html


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