Lower front weight first?

davidlovepianos@comcast.net davidlovepianos@comcast.net
Wed, 08 Sep 2004 03:57:32 +0000


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Balance weight should be equal and I like to set it around 38 grams.  You shouldn't have to worry about FW maximums with the numbers you've posted.  To increase balance weight on the extra light notes you will be reducing front weight and vice versa.  Strike weight should be a smooth curve.  Given all R's and BW's are equal, the frontweight curve will follow the SW curve.  Given equal BW's downweight will decrease as friction decreases with decreasing strikeweights.  Don't worry about the downweight.  If you set the balance weights equal and address friction where it is a problem the downweights will take care of themselves.  With normal friction (15 - 10 grams) at 38 BW the DW will decrease from 53 (38 + 15) to 48 (38 + 10) grams.  
Projection of the piano will depend as much on the belly as on the hammer weight.  Experiment and listen if you are not sure until you get the kind of tone you want.  Likely a small change in the SW is not going to make a big difference, though it might make some.  

David Love
-------------- Original message -------------- 

> Hi Richard, 
> 
> Thanks for your reply. 
> 
> you wrote: Stanwood suggests given SW curves for 
> > each Ratio and BW... 
> > tho you dont see that on most of the Smart Charts 
> > published. 
> > 
> > If you give us some more specifics, perhaps we can 
> > offer better advice. 
> 
> Where are these sw curves suggested in correlation to 
> particular ratios and BWs ? You referred to a number 
> 10 curve. I'll give some more details here about this 
> action. This is with the new hammers. 
> 
> N SW D U BW FrontW R WBWAvg. 
> ___________________________________________________ 
> 1 12.1 56 27 41.5 37.5 5.7 9 
> 2 11.6 56 27 41.5 32.9 5.6 9 
> 9 11.5 50 23 36.5 39.0 5.78 etc. 
> 10 11.7 53 28 40.5 32.6 5.4 
> 16 11.4 48 20 34 40.8 5.7 
> 17 11.1 48 21 34.5 37.1 5.6 
> 28 10.8 48 25 36.5 32.1 5.5 
> 29 10.4 44 19 31.5 35.2 5.5 
> 40 9.7 31.6 
> *(40 10.8 48 26 37 31.6 5.5) 
> 41 9.6 40 17 28.5 33.1 5.4 
> 52 9.5 44 22 33 29.2 5.6 
> 53 9.3 46 21 33.5 27.2 5.5 
> 64 8.3 46 27 36.5 20.3 5.7 
> 65 8.2 44 26 35 19.3 5.5 
> 87 6.6 49 29 39 6.8 5.5 
> 88 6.4 50 34 42 3.5 5.7 
> 
> (*C40 had 1.1 g temporarily added to the hammer) 
> 
> Do I understand that BW should be fairly constant 
> across the keyboard while SW, Frontweight and 
> downweight are going to smoothly decrease? Although, 
> downweight may just decrease from 52 to 48. 
> 
> Also, for good tonal projection is a sw of 12 enough? 
> 
> I hope this info will help you advise me if you don't 
> mind. Thank you. 
> 
> Bob 
> 
> 
> 
> > Hi Bob 
> > 
> > You dont really leave us much to go on here to offer 
> > any real advice. 
> > One of the great assets of Stanwoods method is the 
> > whole slew of terms 
> > and definitions that allow us to easily converse 
> > about and understand 
> > any given touchweight situation. You mention a 5.5 
> > ratio as an optimal, 
> > and that you are having problems dealing with 
> > appropriate Frontweights 
> > for a given Strikeweight curve.. without mentioning 
> > what that curve is. 
> > 
> > To begin with... A 5.5 ratio will yield a number 10 
> > (if I remember 
> > right) curve assuming a 9.0 whippen radius weight 
> > and a 38 gram BW. 
> > This will also yeild the maximum Front weights 
> > published in the Stanwood 
> > kit. 
> > 
> > From that perspective... it doesnt really matter 
> > which you do first.. 
> > All that matters is that you do your diagnostics 
> > right and arrive at the 
> > correct Balance Weight Ratio... (SWR). 
> > 
> > 
> > The point is... when you know your Ratio, have 
> > decided upon your desired 
> > BW... the rest is more or less given. You can 
> > juggle SW curves if you 
> > want... but 
> > 
> > Cheers 
> > RicB 
> > 
> > 
> > Bob Hull wrote: 
> > 
> > >These are questions about component touchweight 
> > >balancing with the SmartChartTM. 
> > > 
> > >I have put new hammers on an action and I'm working 
> > on 
> > >getting the strike weight smoothed. There are a 
> > good 
> > >many keys that exceed the front weight ceiling. The 
> > >leading doesn't "look" excessive like some leading 
> > >I've seen before. 
> > > 
> > >A strike weight ratio of 5.5 is what I understand 
> > to 
> > >be best for this piano. 
> > > 
> > > 
> > why... specifically ? 
> > 
> > >Should the front weight issue be adressed first 
> > even 
> > >if it has to be adjusted again? The strike weights 
> > >will need to be adjusted mostly upwards. 
> > > 
> > >I'll appreciate your comments. 
> > > 
> > >Bob 
> 
> 
> 
> 
> 
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