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Hi

Samick upright piano -

I just started seating the strings on the bridge by gently pushing with a wooden dowel. The strings began "pinging" down into place quite audibly and with a distinct clicking movement as it released from the notch in the pin.

I stopped to check my texts as it seemed a little 'robust' of movement despite my gentle pushing.

1) Reblitz says to push the 'strings' onto the bridge. As I was doing.

2) Pianos inside out says never push the strings onto the bridge as you will dent the hardwood. It advocates a sideways 'pull' of the string 'toward' the bridge pin. (Not 'away' from the string as I would have assumed - to release it from the notch it floats in so it can drop from this notch down to the bridge??)

And another source says to tap the pin to lower the pin 'and' string without removing it from the notch formed in the pin.

On these strings I was seating there was a definite 'click' as it popped out of the notch and down onto the bridge.

I am a little confused as to which technique is appropriate.

To compound the issue -

Someone just posted some great illustrations of seating the strings in the brass rod thread and they were doing it on the non speaking side of the bridge.

Are there varying opinions about this?

I was wondering how the string in its notch on the speaking side of the string bridge pin would be affected.
If seating from the non speaking side wouldnt the string on the speaking side bridge pin still be floating above the bridge in its worn bridge pin slot?

If there are notches on the bridge pins there are much bigger issues at hand and one might need to consider repinning the bridge. Generally one avoids over manipulation of the speaking length. One shouldn't play with it much beyond string leveling. If one has properly seated the string on the bridge pin and clarified the bends of the wire at the back length after raising to pitch there should not be an over obsession of tapping each string at the bridge. Generally one can tell where its sitting and the lightest of taps to properly position it is all that is needed. I think it is best to start with a coaxing of the wire especially in the treble where one needs to space the strings at the capo or pressure bar.

Tapping on a bridge pin to "move the wire while in the notch" is going to create problems, and more then one started with. Remember that seating strings is more about a solid termination of the speaking length and ensuring good contact with both the bridge pin and the bridge itself.

<about the "dents", the bridges are always dented somehow, and designed for those dent to happen, to add more one must be really brutal, as I suppose the wood under the wire is yet dense and compressed.

But anyway gentle taps or massages is all is needed

Thanks.

So -
What issues might cause notches in the bridge pins?

Also, the bridge pins seem tight and do not depress if i push on them gently with the wood dowel.
I am only guessing there are notches but the clicking could have just been the string breaking free I suppose. But I did feel i was pushing the string too low and perhaps 'bending' it out of position slightly.

So, I seat the strings at the non speaking side of the bridge pin. Lightly.

How do I clarify the strings at the back end?

And what is coaxing of the wire?

Lastly - I'm starting to get the picture that seating the string on the bridge should only really be done as a last resort when trying to eliminate a false beat.
NOT as part of maintenance or regulating.
Am I getting closer now?

It depends how the piano is played, strings raise in the high treble more than wanted.

if a tuning done after one year, it can be done generally , in treble and high treble.

Not much on pianos lightly played.

Yes it clicks even without dents in the pins, but dents arise, the string vibrates and rub, steel against steel it can create that.

Have alook at the pin's level, if a pin raised it can be noticed. it is relatively rare. tapping with a light hammer and a hammer shank you hear/perceive it if the pin is firm in the wood.

greetings,
Any downward pressure on the bridge, via the string, will increase the depth of the depression left by the string in your bridge cap. You want the least of this! Strings will often have a lot less tension in the back string due to the bridge pin's stagger, and a disturbance at the pin will allow this equalize. This is one source of the click you hear, and you will often hear this on bass strings if you put a pair of pliers on the loop's barrel and gently twist it from side to side.

Other than that, the yearly movement of the wood in the bridge will often leave the very proximal point of contact, behind the speaking length bridge pin, off the bridge. You can usually settle the string back down with a light sideways tap on the string, in the speaking length, directly towards the pin. This is so light of a tap that a wooden hammershank should not be damaged by doing a whole set of strings. I personally use a very small hook and lightly pull the wire towards the pin with a light massage just proximal of the pin. This is not a permanent fix,but will often cause a string to become more focussed during the tuning. I have a number of often tuned pianos that respond well to this on certain notes about twice a year.

Sideways force on bridge pins tends to loosen them, and this is a primary suspect in false beats, so, caveat Jubal !
Regards,

Brass and copper plated mild steel bridge pins will indent very slightly from the string. The nickel plated and stainless pins do not.

I prefer the softer pins as I "think" the sound is warmer. I have not done a bridge with a variety of pin types to test this. I simply cannot afford that much rework to return a test piano to "normal".

Its my feeling that the setting of strings on the bridge is not something that should be necessary on a regular basis. Perhaps as often as leveling the strings. Obviously, after a restringing, training the wire and setting it on the bridge is part of it. Well made pianos, and those well prepped shouldn't need to be touched for some time. Lesser instruments OTOH, may never have had it done. Normal seasonal movement, I would think, shouldn't make it necessary, unless there are rather extraordinary circumstances. But if there was that much soundboard and bridge movement to have unseated the strings or altered deflection angles, perhaps as a result of a very low humidity situation, I would be concerned about other structural issues as well. As the Baldwin accu-just hitch pin taught us, one doesn't need much down bearing for it to work. But it is imperative IMO that the bridge pins be absolutely secure in the bridge, which to me means an ample gauge bridge pin and well drilled holes. On cheaper grands of my acquaintance most of the tone problems they have seem to be a result of a.) poor bridge notching, b.) narrow gauge pins, c.) shallow drilling for too short of a bridge pin.

As my Baldwin F rebuilding project comes to an end I have my eyes fixed on playing around with a Samick grand with lots of bridge and bridge pin issues (to name but a few).

Unfortunately all intense playing impact the bridge/pin setting on grand pianos (less on verticals).

I would buy the seasonal changes (wood contraction) but seem to me the motion of a bridge cap is infinitesimal.

I believe the whippen effect on the wire make them rise or tend to rise when the piano is played strong.

A possibility also that the pins are put in motion by coupling with the wire, those motions allowing the wire to rise... This is difficult to buy , but what do we know about the motions of the wire at that place ?

I would think that with adequate downbearing the strings may tend to stay on the bridge but that is, and always the thin ones (while all the strings can be seated , the basses included, and that is reduced by massaging and straightening the bends .

It should be interesting to see the computation : how much string imprint is allowed to maintain, the correct contact point at the pin?
Due to the way the strings are strongly massaged in factories the bridge may have some imprints when the piano is new (the strings are pushed really strong, on vertical pianos anyway)

Once compressed, the wood under the strings is harder, I am unsure it is so sensitive. It depends of the quality of course.

During grand tuning something to massage the wire in front of the bridge is to be available at hand. It is often noticed as hammer mating problem, left string, corrected often just pushing the wire in its original location.

SOme tuners tap very hard on the wire, creating more wire/bridge contact, and believe they have "added downbearing" as the tone is stronger.

I have seen that done, and probably it was told by someone.

The effect of better energy transmission is evident, but due to the hardening of the wood under the string, and may be a larger contact surface.

No doubt the bridge is to be recapped when new strings are planned then.

P.S yes I know .... dont scream !!!

Hi Ed

So are you pulling the wire horizontally towards the 'bridge; pin? Or are you pulling it away from the bridge pin and toward the 'tuning' pin?

thanks
Ben

The pressure is towards the bridge pin. On a grand, I use the hook in my right hand, and when I can't hear or see a clear center to a string's pitch, a very light massage, as though I was trying to straighten out the wire's curvature in the speaking length, just proximal of the bridge pin, will often clear things up. Though haven't measured, I would be surprised if I am using more than a pound of force.

I give the back string a light press towards its respective pin before doing this, just in case there is some amount of curvature left in the wire behind the bridge. It sometimes occurs that I hear the string move across the bridge pin when I do this. If that happens, the the speaking length wire will have some curvature that goes away with a light massage.

All this manipulation of the wire carries a risk of loosening a bridge pin, or denting a bridge cap. Small dents, or kinks in the wire, while not ideal, will rarely cause there to be any difference in sound. I tuned an upright piano for some years without noticing that there was a severe kink in the wire around C4, down near the bridge. It never made a difference in how that unison tuned, so I don't' think it makes any difference what you tap wires with, just how hard they are hit.
Regards,

It is also a good idea to loosen the bend at the front after a pitch raise, to help wire motion on the bridge.

Straightening remaining curvature done in a second stage, is indeed efficient to clean the tone.

Too strong tapping on the bridge lessen the amount and force of partials, reinforcing fundamental at the expense of the "halo" in the ton e (and may create some dullness and false beats at worst)

Experiences have been done by adding some thin steel plate under an unison seem to show that a harder material add energy transmission.

Stiffer or less long back length is effective that way (as shorter strike dimension) less deformation of the wire at impact time mean better energy.

Excellent, thank you.