At 11:08 -0700 23/4/10, Bob Davis wrote: >I hope this doesn't show up twice, but I posted it yesterday >afternoon at 5:30 and haven't seen it, so I'm going to try again, in >case something went awry. > >Dear 19th Century Experts, > >We just got in an 85-note straight-strung Broadwood, about 7'2", >maybe 1870's but could be later, for some work. It's all original, >looks clean... That's the way I'd keep it. Its value as a musical instrument is little enough as it is. If you make the modifications you are contemplating it will be less. >...It came in about 1/2 step low in the bottom, drooping gradually >to about 1 1/2 steps low at the top. I was hoping to pull it up to >pitch just to make sure if it was going to fold up, it would do it >now while it's cheap. However, I got it up to about 50 cents low, >and five strings have broken, so I don't see much hope for 440. Spot >tension calculations indicate around 120-130 pounds through the >plain wire @ A=440Hz, unison tension in the bass 260-300. This piano >was probably designed for 448-454, so I was hoping to string it and >tune it to 440 successfully. Any reason not to? Any argument for >taking everything down a half size? Why did the strings break with such low tension? Why would you want to lower the tension any further? >The plate webbing is cast, with an integral flange up against the >stretcher, which should make that part fairly strong. There is a >hitch panel, which is not particularly thick, maybe 1/4". It is >connected to the beams with nose bolts, and to the webbing piece by >two fairly hefty struts (between string sections), which are butted >up to projections on both pieces, secured by flanges (the metal >kind, not the bushed, rotating kind) with big screws. A roughly 1/2 >inch x 2 inch bar is screwed to the straight side as a similar >stretcher/connector, and another at the treble end. There are also >fins connecting the webbing panel to the belly rail. Decent but not >enormous beaming underneath. > >Second question - I've heard of bass strings where the winding >continues on across the bridge, but why? They also have cloth sleeves where they cross the bridge. It gives them that inimitable Broadwood sound. If you don't replicate the design then you'll make a big difference to the downbearing. >And is there any reason to duplicate that? Generally speaking, the >owners would like a piano which is playable at 440, while retaining >as much of its character as possible, so although we'll replace the >pinblock, we'll retain the original tuning pins. Really. (And I hope >none of them shear). They won't shear if they're loose, and if they're not loose why replace the plank? >Finally, who's had experience with Pure Sound wire, and would it be >appropriate? By 1870 everyone was using wire much stronger than PureSound. I have chosen not to gain any experience of PureSound. JD
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