Carol Beigel wrote: > It never occured to me to measure the upweight. I assume you do this in > reverse - put damper pedal down, put a weight on the key, and see how much > weight is sitting on the key as it begins to rise? > > Are you saying, that by removing friction (cleaning pins, using teflon > powder on knuckes, protech on hammer lever flanges) to adjust the > downweight, that if the ratio of upweight to downweight is not correct, then > the problem will reoccur when the friction returns? No... I'm just saying that you cant just assume you have a friction problem unless you know what your friction levels are. Just because DW changes as you have described does not mean necessarilly that you have a friction problem. If you had 10-12 grams of friction origionally with a 65 gram DW, then you have an action with a 54 - 55 gram Balance weight... and in that case your problem is definantly not friction related. Bostons I've seen the past couple years ususally come in with somewhere around 40 grams BW...which is in itself starting to get a bit heavy touchwise. To get that with 65 grams of downweight you'd have to be seeing an upweight of 15 grams... which would defninatly show up in your initial comments in terms of sluggish sticky play What you did mention was heavy play, lots of DW which came back after applying fairly routine first aid friction control. This adds up to a potential BW problem if you ask me, and I wouldnt rule it out unitil I had the measurements to be sure. Nor would I start advising you to do this or that until I first advised you to take UW measurements and take a look at just what friction and balance weight levels you are looking at. That you managed to temporarilly reduce this DW by employing some friction reduction measures that very often end up being shortlived. Teflon powder comes off knuckles easily, and cleaning centerpins is a 50 - 50 proposition as best in my experience. All this said... it may indeed end up being largely a friction problem.... but I'd be willing to be its somewhat exhasperated by an action thats a bit heavier then perhaps it should be to begin with. > This is a Boston grand action on a 7 foot piano - only two years old. I > thought these things were designed by Steinway and built by Kawai and > supposed to be good. Am I still missing something here? Thanks for the > responses. > > Carol Beigel > Dont take anything for granted. Perhaps the keyleading was done with extremely low friction levels... we just had that conversation.. :) Besides... When you first are doing DW measurements... it should be just a natural to take the UW measurements as well... Quickly done, and gives you much more information to go on. DW alone really doesnt say much at all. Cheers RicB > > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html http://www.hf.uib.no/grieg/personer/cv_RB.html
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