Roger action Geometry

[Richard Brekne]

Roger Jolly wrote:

>
> >.
>
> Hi Richard,
>                  Since the springs are only supporting 5-10gms it stops
> that wip bounce, before when they were supporting 30-35gms, and noisy.
> Changed the jack spoon felt buttons,  (nice soft red type) also a big
> reduction in noise.

On mine, removeing the jack springs entirely had no effect on the amount of
whippen bouncing. Sounds crasy, but the keys were so lightly weighted that the
weight of the whippen / hammer literally threw the key downwards. You could see
this happening. They wouldnt reach bottom at the same time and the result was
blubbering until all settled down.. very noisey stuff. Increasing the front weight
a bit (there was like almost no front weight to begin with ) slowed the key down
just enough to lick this problem. But no doubt a whole lot more woulda needed to
be done to really make the thing play well.

>
> T
>
> Gina and I have some good photos in upcoming Journals re tailing.

Good deal, nice series by the way.

>
> Unless you get hammer mass, bore, rake, and tailing correct, it's a futile
> exercise to start a serious weight off. ... snip snip

This of course was my thinking in regards to the whole Stanwood process.. But as I
havent really had a chance to dig deeply into that yet, I will take the time to go
a bit overboard with those measurements and figureings...grin.. Still I have to
aggree that getting the geometry at optimal first has got to be the right first
step.


I am gonna be really interested to see in the end how Stanwoods modeling of the
system handels geometric problems. There seems to be some potential problem here
with relocating capstan. I am not yet convinced that following Stanwoods specs
will result in an optimal geometric positioning for the capstan in any given
action.  But perhaps it will. Looking forward to this little adventure. grin

>
>
> Dry hang the hammer at various weights then do the DW/UW measurements. as you
> increase hammer mass 1gm, a rough rule of thumb for DW is 5gms.  Most times
> just selecting the right hammers for the job can save a lot of extra work.
>

Here is an area where I definantly gotta suggest one looks closer at Stanwoods
method. Instead of Dryhanging, one can choose a desired Strike Weight and Strike
Weight ratio and work the balance equation in the direction of solving for Front
Weight. (This works great on paper anyways,,,grin... I'll let you know how it
works in reallity as soon as I myself know..hehe). In anycase the obvious gain
here is that knowing ahead of time how much each hammer assembly is going to weigh
saves a lot of time. Secondly I like the idea of a consistant graduation of strike
weight. You might start thinking a bit along these lines Roger... play around with
it a bit in your thoughts. See what you can come up with..grin.

I'll be in touch about the Petrof...

>
>
> Roger Jolly
> Saskatoon, Canada.
> 306-665-0213
> Fax 652-0505

--
Richard Brekne
RPT, N.P.T.F.
Bergen, Norway