Hello Mark,
You haven't said anything about the size and/or make and value of the piano. I wonder if this piano is a case of where the owner should cut the losses and rather put the money toward a better instrument? It sounds rather like a bushel of trouble. For instance, is it a short piano with a short backscale length for the bass strings?
You mention "some of the bass strings have gone dull", which suggests that at least some are not dull. In that case I think your primary issue for the bass tone quality (especially in view of the rattles) is the strings themselves. But you can test that quite readily by just picking one of the dull bass strings where you really have nothing to lose and see if changing the twist improves the situation. I have done that on some occasions and had success for some and for others not. In one instance it turned out that too much twist on the string had caused it to go dull; another time adding some twist brought them to life (which I can't now recall if it was a half turn or a full turn). You can test and gauge the amount of twist by clamping a small vise grip plier onto the loop section, loosen the string by turning the tuning pin just enough to allow you lift the loop off the hitch pin with the plier attached, then carefully allow the vise grip plier to rotate in the direction it wants to go while counting the turns (don't just release it, instead control the turning while allowing it to untwist). The amount of turns the string unwinds will give a clue what to do: if they come off with no twist then try adding a turn. If they come off indicating a significant turn amount then you may want to try reducing the turns.
But in the case of rattling bass windings, I doubt you can do much about it. I suspect it's just a case of poor (read "cheap") set of bass strings.
Re. the metallic sounding and zinging plain wire strings - you don't indicate if those are in the agraffe section or the v-bar section or both. If you suspect it's the agraffes themselves then you won't be able to do anything about without replacing strings, in which you can consider using this Walter Titex K1113-1.6 countersink bit
to recondition them, available from MSC Direct (see <www.mscdirect.com>):
Metric Radius Cut 60° Incl Angle High Speed Steel Combo Drill & Countersink 4mm Body Diam, 1.6mm Point Diam x 4.25mm Point Length, 35.5mm OAL, Right Hand Cut, Double EndMSC Part #: 01032259,
Mfr Part #: 5073546
Bar code #
4031132158983
Made in France
But new agraffes might be a better bet?
If the v-bar is grooved and source of the zinging, you can consider "machining" it to eliminate that source of false tone. Daniel Farrah in Canada has a good method for that, which you might want to explore.
But, as I mentioned at the outset, consider if the value of the piano warrants any such effort. Unfortunately the previous work proved unsatisfactory, and can you guarantee repeating that work will produce good results? All the money spent on repairs both past and future would be a significant amount toward a better instrument.
I could suggest an option for the bass bridge too, but the scope of this project sounds like it may be getting out of hand?
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Ernest Unrau
Morden MB
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Original Message:
Sent: 02-18-2020 06:03
From: Mark Davis
Subject: Advice needed
My thoughts on the matter,
1. The downbearing needs to be reduced. Not sure exactly how to do that. Any advice on how to do this would be appreciated!
2. The bass strings may not have turned when installed so hence the dullness and rattling and metallic zinging. So, they could be checked when addressing the excessive down bearing. If they have not been turned then I would turn them and once retensioned and tuned see if they have improved, if not I would need to quote for new bass strings.
3. The metallic sounds, sizzling and zinging may be hammer to string mating (I forgot to check this) wear in the agraffes and capo bar areas.
4. I am fine with hammer filling and hammer to string mating but have never addressed agraffe and capo bar string groove removal/filing. Not sure how difficult this is and how much time it would take and how to price for it?
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Mark Davis
Piano Tuner/Technician
Original Message:
Sent: 02-18-2020 03:45
From: Mark Davis
Subject: Advice needed
I recently tuned an old grand piano, approx 80 years old, for a new client. New tuning pins, steel wire and bass strings were installed in this piano about 4 years ago.
The sound is constrained, some of the bass strings have gone dull and others are rattling and metallic sounding and many of the steel wire strings have metallic zinging and sizzling in the unisons.
I have checked the crown, which is currently at 0 to 0. 5mm and downbearing which is about 3 to 4 degrees across the scale.
The mechanism was also restored with new Abel hammerheads (not natural felt) installed too.
All the work was neatly done but the grand has these problems.
Any advice on what should/could be done on this grand would be appreciated.
Thank you.
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Mark Davis
Piano Tuner/Technician
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