> One other thing that comes to mind is if the wippen heal/capstan interface > starts out way above a line drawn between the key/balance rail contact > point > and the wippen flange center pin, then the vertical travel of the wippen > will be reduced. More so if the capstan and wippen heal are both angled. > If you haven't already checked this I would and if that points starts way > above the line then cut a thick piece of action cloth and insert it > between > the heal and capstan and turn down the capstan. See if that doesn't buy > you > some additional hammer travel. Perhaps you've already checked this. ****Yes I have checked this carefully - the line bisects the whippen heal/capstan interface throughout its travel. > > With the front weights you've given removing lead from the keys seems a > low > priority if necessary at all. > > David Love > www.davidlovepianos.com > > -----Original Message----- > From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On > Behalf > Of Gene Nelson > Sent: Friday, March 13, 2009 8:39 PM > To: pianotech at ptg.org > Subject: Re: [pianotech] high leverage action > > > > >> >> That being said, I'm something that on the surface seems at odds. Deep >> key >> dip combined with shallow blow suggests very low leverage yet the weights >> you describe (low SW's, medium FW's and relatively high BWs) don't seem >> consistent with that but rather with a higher leverage. Have you actually >> set the regulation in the piano as opposed to on the bench to be sure >> that >> there isn't some bedding difference that might account for the regulation >> oddity here? I would want to resolve that apparent discrepancy before I >> pursued major action modifications. >> > ****Yes, regulated samples in the piano and on the bench. The key frame is > bedded - did that before I took the bed to hammer flange distance > measurements. > > If there are minor discrepancies it is because the hammers and whippen > heals > > are not glued on yet - just stuck on lightly with a post it pad type > adheasive. > > Other factors that I cannot figure is that the Tokiwa whippen for the > Knabe > fits ok but the distance from the whip flange center pin to the jack > center > pin is less on the Tokiwa than the original by 2mm - not certain if this > affects leverage or not. It does not help with knuckle/jack alignment. > I have both whippen heal sets - short and tall - either seems to work ok > and > > I cannot see any differences. > > Not mentioned was the key leading pattern - three 1/2" leads in the bass > tapering to one in the treble and I think that I can remove the one in the > top octave. > > The whip rail is adjustable and I will play around with the spread > tomorrow. > > Gene > > >> David Love >> www.davidlovepianos.com >> >> -----Original Message----- >> From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On >> Behalf >> Of Gene Nelson >> Sent: Friday, March 13, 2009 7:35 PM >> To: pianotech at ptg.org >> Subject: Re: [pianotech] high leverage action >> >> >> Thanks Dave, >> >>> I would guess that the hammers are bored too short or worn--check again. >> >> ***** The hammers are new and I have just bored them and they are correct >> based on string height and hammer flange center height - no need to >> recheck >> something that I have already rechecked at least two dozen times. They >> are >> light but I have a 5 pound roll of lead wire to help bolster their mass >> and >> intend to use it. >> >> , play with the spread a bit and see what you can do in terms of >> changing >>> the dip/blow balance, >> ***** At 113mm I suppose this normal number may be excessive for this >> action. I have not played with this yet. >> >> otherwise, on this piano power is probably not that >>> much of an issue and redesign costs might be prohibitive. Keep it >>> simple. >> >> *****This piano is my spec piano and has a new custom board, redesigned >> scale and bridge. As with so many aspects of novice rebuilding it is not >> easy to see difficult issues before they manifest. >> I am not opposed to action redesign but would like to make this one work. >> It >> >> is my education so the expense is worth it to me. >> >> Gene >>> >>> >>> David Love >>> www.davidlovepianos.com >>> >>> -----Original Message----- >>> From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On >>> Behalf >>> Of Gene Nelson >>> Sent: Friday, March 13, 2009 4:52 PM >>> To: pianotech at ptg.org >>> Subject: Re: [pianotech] high leverage action >>> >>> >>> >>>> Hmmm... I think we'll have to be a bit more specific then that. A 10 >>>> gram >>> >>>> strike weight in the top low strike weight zone equates to something >>>> around hammer number 5. A weight of 5 at key 88 is perhaps a quarter >>>> zone >>> >>>> higher... that means you have really low hammer weight if this is >>>> reflective. >>> ***** I will probably push the hammers up to number 6. As I said, I have >>> not >>> >>> done any corrective hammer leading yet. >>> >>> Front weights... assuming we are balancing the >>>> same notes you mentioned for hammer weights then you have an action >>>> ratio >>> >>>> of 6.2 in the bass ranging to 7.8 in the treble. Kind of wild... but >>>> suffice to say you have a high action ratio... which fits at least your >>>> KR >>> >>>> and Knuckle configuration. Without more specifics this is just ball >>>> park. >>> >>>> I'd ask for at least 7-8 samples of SW, FW, BW, and KR along with your >>>> WW >>> >>>> to get a more accurate picture of your situation... say all C's but I >>>> think its safe to say you have a pretty high action ratio....no matter >>>> which way you look at it. >>> >>> ******My samples were not all C's but they are all naturals, first and >>> last >>> in each section. - here it is: >>> note# SW FW BW KR WW >>> 1 10 30.1 41.5 .55 16.4 >>> 25 10 26.7 42.5 .52 16.4 >>> 27 9.3 23.8 39.5 .54 16.4 >>> 45 8.4 15.5 44 .54 16.4 >>> 47 8.7 16.6 42.5 .53 16.4 >>> 66 6.8 7.7 42.5 .54 16.4 >>> 68 6.5 6.5 41.5 .54 16.4 >>> 88 5.0 6.8 36.5 .53 16.4 >>> Note that the WW value is the same because it is the average - the range >>> was >>> >>> from 15.9 to 17.2 >>> >>>> >>>> Why you end up with such a short blow distance and deep key dip to get >>>> any >>> >>>> aftertouch is a good question if the above is close to the truth of the >>>> matter. A short bore length would force you to raise the shank closer >>>> to >>>> the strings... ie raise the underlever (whippen) which should not >>>> require >>>> a deep key dip to get aftertouch. A long one would keep your shank just >>>> off the rest cushion at a shorter blow distance... and perhaps fit the >>>> condition of a high action ratio thats heavy, has keep key dip and >>>> short >>>> blow with minimum aftertouch. But if you are certain about bore length >>>> being at String height - hammer shank center height then something is >>>> not >>>> quite right with this whole picture.... grin.. or its just so late over >>>> here that I've got things backasswards again.... wouldnt be the first >>>> time. :) >>> ****I am absolutely certain that the bore distances are based on String >>> height - hammer shank center height. >>>> >>>> As far as minimum 44 mm. I think thats about as short a blow as you >>>> can >>>> allow for without sacrificing too much power. Usually you find >>>> somewhere >>>> between 45 and 49... sometimes 44... sometimes 50.... rarely outside >>>> that >>>> because of what implications it has for the rest of action regulation >>>> specs. We have this ideal of about 10 mm key dip, and about 1.5 to 2.5 >>>> mm >>> >>>> letoff... which more or less dictates blow for any given amount of >>>> aftertouch. It all adds up usually to somewhere between 44 and 50 for >>>> blow. >>> **** I measured the height of the sharp blocks to get an idea of maximum >>> key >>> >>> dip. Not that I like that much necessarily. >>> >>> Gene >>> >>>> >>>> Cheers >>>> RicB >>>> >>>> >>>>> >/ What are your Hammer Strike weights >>>>> /*****10 in the bass and 5 in the treble - no corrective weighting >>>>> action >>> >>>>> taken yet. >>>>> >>>>> and key Front Weights ? >>>>> ***** >>>>> 30 in the bass and 6.8 in the treble >>>>> >>>>> Your dip >>>>> >/ and blow say low ratio but your KR and knuckle distance says high. >>>>> >How >>>>> />/ much aftertouch are you getting with things as they are... >>>>> /***** about 1.5mm or slightly less. >>>>> >>>>> how far out >>>>> >/ from under the knuckle does the jack move ? >>>>> /*****Just enough for drop and aftertouch to happen. >>>>> >/ >>>>> />/ 41 mm is on the short end of the stick to be sure. I usually dont >>>>> see />/ under 44 and never allow for less when redoing an action. >>>>> /***** Do you have a reason for maintaining 44mm or greater blow >>>>> distance? >>>>> >>>>> Regards, >>>>> Gene >>>>> >/ >>>>> />/ Cheers >>>>> />/ RicB >>>>> />/ >>>>> />/ >>>>> />/ Hello list, >>>>> />/ Thought that I would seek comments on an action with high >>>>> leverage. >>>>> />/ Key dip is 10.5mm and blow distance is 41mm. >>>>> />/ The touchweights are in the low 50's down and low 30's up. >>>>> />/ Knuckle spread 16.5mm >>>>> />/ Key ratio is 1.81 >>>>> />/ Action spread is 113mm and is adjustable. >>>>> />/ Any more dip will make the sharps about level with the naturals >>>>> when >>>>> />/ depressed. The feel of the samples are acceptable. Seems that >>>>> 41mm >>>>> />/ blow distance is short - but is it too short? Maybe some loss >>>>> of >>>>> />/ power? Is there a down side to this action? Any corrective >>>>> />/ suggestions? It is in the sampling - disassembled stage. >>>>> />/ Thanks, >>>>> />/ Gene >>>>> />/ >>>>> />/ >>>>> />/ / >>>> >>> >>> >>> >> >> >> > > >
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