At 06:43 PM 1/31/97 -0500, you wrote: >List Members, > >I have what I think is a 1930 Steinway B with a telfon action >that has been installed / serial # 272377. The key frame >is replaced & .147 balance rail pins , originals would have >been .160, and the half round "accelerated" dowel. >Hammer c/p to wippen c/p = 4 1/2 " >Hammer c/p to hammer center = 5 1/8 " >Keybed to hammer c/p = 5 3/4 " >Are these numbers close? >The action feels like a truck down weight started out at 85 gr. >with an up weight of about 40 - 41 gr. With some weight removed >from hammers and shanks and some other friction problems - >got down weight to 69 gr. there are still a lot of problems. >Question is can this ever work? I think the best thing would be to >start over again, but the client just got the instrument (should >have called a tech first) . The piano really sounds pretty good >refinished and re-strung w/ new block - soundboard is in very >good condition. Just wonder if I'm spinning my wheels and >wasting time and client money on this current action? > >Any help or input on this would be greatly appreciated. >Mark Ritchie RPT >Cols OH > > Mark, June issue of Journal, pages 16-18 show David Stanwood's article. The numbers you have here initially shout hammers heavier than keys. Balance weight is way off. Friction levels will change after repinning parts (see below) Leverage needs calculated (under leveraged aids in same results). On about 6 or 8 sample notes, take the measurements according to the article. You'll need Note DW UW BW Fric Strike W FKeyWt KeyRatio WipWt WipBalWt TopBalWt StrikBalWt Strike Ratio. The formulas are given in the article. A spreadsheet is easily created for a working table like the one below. The first example is taking your UW & DW (with assumptions of SW, FKW, WpWT & KR) The SR on this scenario is incredibly high (excessive friction will do this as well) DW UW BW Fric SW FKW KR WpW WBW TBW SBW SR 85 40 62.5 22.5 10.7 33.1 0.496 17 8.432 95.6 87.168 8.15 Other Sample Stuff 51 19 35 16 11.9 46.1 0.53 18 9.54 81.1 71.56 6.01 52 22 37 15 10.9 49 0.52 18 9.36 86 76.64 7.03 47 23 35 12 10.2 28.2 0.51 18 9.18 63.2 54.02 5.30 60 42 51 9 11.4 22.1 0.48 18 8.64 73.1 64.46 5.65 60 40 50 10 11.9 46.1 0.53 18 9.54 96.1 86.56 7.27 60 40 50 10 11.6 24.7 0.49 18 8.82 74.7 65.88 5.68 Repin all teflon parts (on a few samples). Dry teflon powder knuckles, polish capstans, and be certain that the rep spring isn't binding in lever---keys/bushings can create alot of friction all by themselves---free them: do UW & DW again. This should change numbers dramitically. The existing parts should be replaced anyway. New Renner samples applied ( regulated, rep spring tension, checking, etc.) will greatly improve your numbers...chances are you will need to move your capstan down a bit (which is good-improving leverage). Create your straight line from balance rail pin to whippen flange centerpin (I use a piece of thread). Optimal line-up would be capstan moving through the line at half keystroke. Spread is close...4 13/32 might be better. Try with Renner samples and check spread measurement, you may find a slight difference. Other numbers ok. What shank is used? (most likely the brown knuckle 15.5 centerpin to knuckle core). If so, remember that this is a low leveraged shank...houses less hammer weight. Using the new Rennner modified 16.3 (correct me list, it might be 16.5) allows for less hammer weight reduction=higher leverage. The larger size Steinways do seem to vary from one piano to the next...B's & up. S,M,L seem more consistent. Considering that the instrument is a "B", it is well worth replacing the action components with superior parts. Taking these crucial measurements will also aid in the determination of other problematic areas. David Stanwood offers application of his patented weighting system as well as complete re-design, hence the New touchweight metrology. You may write to David at the following e-mail address: stanwood@tiac.net The existing parts, even if one were to spend all the time and effort replacing teflon/repinning, still would not be nearly as nice or long lasting as new parts. You'll extirpate many demons choosing new parts and your customer will play with immeasurable joy (I was going to say jump, but...). Best wishes Dave Swartz, RPT dms2000@pioneerplanet.infi.net Majestic Piano Website: http://www.majesticpiano.com
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