[CAUT] Shank to Hammer weight spreadsheet

[David Love]

Yes, I understood that to be your procedure. 

My own method using a table saw to taper all hammers pretty much from the
tip of the tail to the top of the molding, I've found, produces hammer
weights where you don't have a .5 gram difference between adjacent hammers.
I spec out the action first and make a predetermination as to how much I
want the hammers to weigh (approximately) at note 40 and the lowest note in
the tenor.  The amount of initial taper will depend, then, on where
approximately I want the SW zone to be when everything is assembled.  As I'm
tapering the hammers I have the gram scale handy so that I can weigh the
hammers on either side of the bass break.  I often will alter the table saw
jig to take off a bit more as I go down through the bass so that the hammer
weight transition is a smooth one between the tenor and the bass.  

Once I'm done with that I simply dry assemble the shanks and hammers and
then use the Stanwood scale to weigh the SWs.  I chart those and then figure
out where I have to alter them to achieve a smooth curve.  It's an eyeball
method and I make an attempt to achieve the curve with the least amount of
manipulation. Rarely do I need an alteration as much (or greater) than .5
grams.  More often it's in the .3 range.  I don't alter at .1 but do at .2
or greater.  Typically, I opt to build up rather than pare down but if I
need to remove some weight a simple additional pass through the table saw
with a slight shaving does the job neatly and cleanly with no hourglass
shape.  Yes, craftsmanship and appearance do count.  The addition of lead
solder to the molding serves to add weight and is not visibly offensive.   

Either method works.  My own experience having done both is that this method
is much faster.  I've found that the method you describe often leaves some
alteration to be done anyway as I haven't been able to find the perfect
match for the hammer and shank weight variations to make the curve work
without some additional work.   My method involves only one weighing and
charting as opposed to two and also combines the dry fitting of the pieces
in the process.  I presented it as an alternative to those who want the same
result and value a smooth strike weight curve but want to get it in a
shorter time--at least it's shorter in my view.  But, to each his own.     

David Love
davidlovepianos at comcast.net 
www.davidlovepianos.com

-----Original Message-----
From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of Jon
Page
Sent: Sunday, February 17, 2008 5:11 AM
To: caut at ptg.org
Subject: [CAUT] Shank to Hammer weight spreadsheet

If pinning is an issue, repin.

As far as weighing the shanks... I'll go through this once more.

The weight range of shanks in any given set is at least .5+ grams.

Let's work with notes 26 & 27 at a bass break.

Now if you pull a shank out of the box for this area it could have
its own SW of 1.6, 1.7, 1.8, 1.9, 2, 2.1 or 2.2 grams.

Let's say that hammers 26 & 27 weigh 9.5 & 9, respectively.

You pull a shank out of the set, it's 2g and place it with 26, SW=11.5g
For 27 you end up haphazardly with a 1.6 shank, SW=10.6g

Now what do you do? Pare down 26? Increase 27? Meet in the middle?

Had you purposefully placed the 1.6 on 26, SW=11.1
then placing the 2 g shank on 27 SW=11

See a pattern?  Whatever the SW is actually, it more than likely IS right
on the curve or an acceptable curve. No further mass alteration required.

The appearance of the set remains intact with no hour glass figures.

Spend time fiddling with each and every individual hammer mass
or spend the time sorting shanks and mating. I've done it both
ways and much prefer the outcome of the later. Because quite frankly,
hammers that have been aggressively pared down look as if some
hack got at the action.

Let's not forget that craftsmanship also entails appearances, after all
why did Studley go through all that trouble of making just another tool box;
to prove what, that he had a lot of spare time?

When it comes down to it, there are some people who think that
a smooth SW is a waste of time.
-- 

Regards,

Jon Page