Terry, I'll run the numbers in my spreadsheet and see what I come up with, but at first glance it looks like you have a combination of too little FW compared to the SW's. Looks to me like the action would need whippen springs to work comfortably. If you look at your worst case notes and compare your existing FW's with the FWceiling you'll see quite a disparagy... . More FW will of course lower your DW and BW right ?? (seems like you had it backwards in your comments below). The erracticness of the action is certainly not much to do with your SW curve. You got that analysed right. But an even SW curve set up against an uneven FW curve is a recipie uneven play. In addition you have a bit of up and downs with your friction... tho none of those figures are particularilly high. Your KR is on the low end of what I usually see... so you should be able to push a good deal of weight upwards,,, which also fits with the low FWs we see. My initial impulse would be to bring up the FW's to conform to the FWC table, take care of all friction concerns and leave it at that. That will improve your situation immensly. If you have helper springs, then you can use a bit less FW. Then when you are done and are runing your BW check, you can mark off how many grams you want to change useing the traditional weighing off style, keeping in mind that you want a pretty even curve of FW. Any isolated key that doesnt fit in with that even curve should point you to look at friction or leverage uneveness for that key. Remember... if you have an Even FW curve AND and even SW curve...then any uneveness is simply got to be found in either friction or leverage. I'll run these numbers... and I am sure David Love will too. It will be fun to compare what we come up with. Cheers RicB Farrell wrote: > Well, I'm trying to plug along here with my Yamaha G5 heavy action. Below is a table of my data for ten sample notes (I hope it comes through un-screwed up). I think all is fairly self explanatory perhaps except for the last four columns. FWC is Front Weight Ceilings (from Stanwood data tables). FWT is Front Weight Targets, which is the FWC, less 10% (safety factor). BWC is Balance Weight achievable with using the ceiling FWs. BWT is Balance Weight achievable with using the target FWs. > > > # DW UW F BW FW KR WW KC SW R FWT FWC BWT BWC > 16 61 37 12.0 49.0 29.0 0.49 18.4 16.5 11.9 5.8 33.8 37.5 44 41 > 17 67 39 14.0 53.0 30.3 0.49 19.4 16.5 11.9 6.2 33.5 37.2 50 46 > 28 59 38 10.5 48.5 23.1 0.48 18.9 16.5 11.3 5.5 30.6 34.0 41 38 > 29 73 48 12.5 60.5 17.7 0.50 19.1 16.5 11.2 6.1 30.3 33.7 48 45 > 40 67 40 13.5 53.5 14.1 0.48 19.7 16.5 10.5 5.5 27.0 30.0 41 38 > 41 72 46 13.0 59.0 13.5 0.50 18.5 16.5 10.4 6.1 26.6 29.6 46 43 > 52 66 47 9.5 56.5 3.6 0.48 18.6 16.5 9.6 5.3 22.6 25.1 38 35 > 53 68 46 11.0 57.0 8.0 0.50 18.4 16.5 9.5 5.9 22.2 24.7 43 40 > 64 62 41 10.5 51.5 2.6 0.48 19.3 16.5 8.3 5.4 17.2 19.1 37 35 > 65 63 41 11.0 52.0 6.7 0.50 19.0 16.5 8.3 5.9 16.7 18.6 42 40 > 76 59 41 9.0 50.0 -1.7 0.48 18.3 16.5 7.3 5.4 10.4 11.6 38 37 > 77 62 42 10.0 52.0 -0.3 0.50 18.8 16.5 7.1 6.0 9.9 11.0 42 41 > > Action spread is right on the money at 112.5 mm. > > My SWs are right along the divide between medium and heavy hammers on the smart chart. I should think this is a reasonable weight set of hammers. I see someone forgot to put lead in the keys along the line somewhere! But I also see that even if I go right up to the FW ceiling, I will be a bit over ideal DWs. > > Not having seen all this data before, it seems rather erratic to me. How in the world can the BWs range from 49.0 to 60.5? And that is with a very smooth SW. I assume this is mostly erratic leading? Leading is two in bass, one in tenor, small one near center rail in treble, and one in rear of key in high treble. I just played around a little with weighting key #16, and I would have to add two big leads and one small one to get near the FW Target or Ceiling. But perhaps that is OK - basically three big leads in the bass keys. > > Recommendations? > > I should point out here that this piano is in a small church, and it seems that the piano is not a high priority for spending money - so I'm probably not going to get to do everything I might want. > > I could trim all hammers, but I hate to have hammers too light for tonal reasons. Geez, I look at this mess and start to think that I simply need to take a saw and cut off everything above the keyframe and start all over. Help! > > I know I can trim hammers a bit, and add lead until I get about to where I want to go, but that seems so........ pre-cambrian. Waddaya think? > > I think I also need to regulate out a few notes to be sure that the current geometry is not requiring excessive dip. -- Richard Brekne RPT, N.P.T.F. Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html
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