hammer that won't detach from the stiletto

Wait for Paolo maybe... he will surely know how to give you a hand..but..would you want to put the new felt back in by yourself?

no I would like to save the hammer and only change the shank. It shouldn't be complicated if the hole remains clean and clear. I have seen that for some people just heating it is enough, but in my case, the glue they used refuses to melt

Understood, understood.. I also saw on my Yamaha that the glue (I think hot glue or some kind of special glue) leaks out even from the hole to form a small raised ring in the wood.. they perhaps give a little more... than what is needed to ensure grip..

You should talk to Paolo... send him a private message if anything..

Or wait until he sees the post.

But how did you try to heat it up?

Try with steam. Put a small pot with water and cover it with aluminum foil. Use a cutter to make a slit in the foil. Steam will come out during boiling. Bring the glued part of the hammer close for a few minutes; the hammer will unglue and you will be able to clean the hole well.

Thank you Pianoexpert. The steam worked, even if with much persistence. I was wondering where I could obtain new hammers to replace them. From Ftp Pianoforte, it seems to me that we only have a few measurements. My measurements are 18 and 13 (from pin to roller). Furthermore, the color of the hammer shank is dark brown (hornbeam? excuse my ignorance....)

I don't quite understand what you have to do...... be careful, the new shanks must bring new hammers and the old ones must remain mounted on the old shanks. Do not unglue the hammers... otherwise you will lose the copying of the striking point. Replacing a hammer rail is something for experts and there is a risk of losing the design measurements. In the old stiletto, furthermore, one must observe the equality with the new one... also regarding the height of the forcola....

I hope you don't want to replace the stilettos by reglueing the old hammers; it would be against all common sense.

Let me explain myself better, Prof. Ferrarelli. The piano is antique with a new action. But ever since it was delivered to me, it has had a problem with the very last bass key. The hammer shank had been poorly glued and also turned out to be shorter. I didn't give much importance to the fact since those are keys that I have never used. Now, however, I would like to correct this as well, and I thought the best thing would be to keep the hammer and replace the shank. If the shank must remain original, how should one proceed in case it has been seriously damaged?

A photo is welcome.

https://drive.google.com/open?id=0B0gPLk9t_1hEY3cwR0FMazNsMms

here is the photo. The rod is shorter than the others.

I don't think you will be able to find the rod, because it seems out of size and with a particular yoke. A new one would need to be adapted, copying the exact measurements, heights, and shapes. However, it won't be exactly identical to the original. Alternatively, with a diagonal cut, glue only a final end piece, obviously longer, using hot glue and matching the color of the old part. (You can try with those special wood touch-up markers - testing first on the new wood to reach the identical shade). After gluing the cut, wrap a good amount of sewing thread around the joint, thread which you will remove after a few days once the glue, after setting, has reached its final hardening (use bead glue to be heated in a bain-marie at a temperature not exceeding 60°C).

Paolo. It would be the classic amber glue, right? Once upon a time it was the old CARAVELLA carpenter's glue, if I'm not mistaken.

Yes that one, the one that is always used on instrument parts.

Anyway, since I use quite a lot of glue, I have devised a way to make a bain-marie that doesn't cause the glue to boil, otherwise I would always have to be there checking it...

antares86 wrote:

Yes that one, the one that is always used on the parts of instruments that sound.

Anyway, since I use quite a lot of glue, I have devised a way to make a bain-marie that doesn't bring the glue to a boil, otherwise I would always have to be there checking...

In my opinion, on new wood, or at least wood not previously treated with hot glues, white glue (PVA) can also be used very well. It is a different case when one must re-glue a failed or detached inlay... then the choice is mandatory. But the statement that hot glue "is what has always been used on the parts of instruments that sound" is perhaps your own consideration, not an absolute truth, given that times and techniques evolve, and given that for example Ciresa (to cite an important soundboard maker) uses specifically a vinyl-type glue for the joints between the boards, which are executed as dovetails, and the same thing he recommends using for the gluing of the soundboard to the rib... to cite a maker who is not "just anyone".... a formidable vinyl glue, but still vinyl and not hot glue... obviously it must be used in the correct way, specifically it must be applied to the two parts to be glued and pressed well...

The same argument applies if it is used for gluing the hammers, as many important factories have done from the 70s onwards... C. Bechstein for example.

Then there are also other types of glues that are used, for key coverings which vary depending on whether it is ivory or plastic... certainly one could not use carpenter's glue to apply ivory, since it is semi-transparent.... nor white glue which turns dark when drying...

Not everything is always so obvious and so simple...

Ok personally I would never use vinyl, especially on the soundboard... Then again, everyone does what they want; at most, I would use it to glue the keyboard board, maybe I'm being too extreme.

Anyway, I wasn't referring to the keyboard, I don't even use the caravella there.

The world of adhesives is also a world unto itself, in fact. I have used many of them in the field of fine arts.

In the field of musical instruments and regarding the performance of certain materials in relation to sound (sound modifications based on the adhesives used), these issues prove to be thorny. It wouldn't be bad to talk about it.

http://www.ciresafiemme.it/images/testate/tavolaarmonica/tavolaarmonica4.jpg

Observe this photo, it is very clear that the adhesive used for the ribs is of the vinyl type, vinilforte or similar... the photo is from Ciresa. But I can also affirm this from personal experience after having used their soundboards and their glues in restorations when it is necessary to replace the soundboard... it happens...

I agree that in the restoration of historical pianos, hot glue of the same type as that used originally should be used, if possible, and we do so if a rib is detached near a crack, if the veneer lifts, or in general when it is not possible to perfectly scrape away the old glue; this is because it is compatible with what was used in the past and can be rediscovered with heat, reactivating it....

but closing oneself off without reason to technology and evolution seems absurd to me; furthermore, stating that "personally one would not use vinyl glue for the soundboard" is equivalent to saying that a leading company in the sector (which supplies soundboards to Fazioli, C. Bechstein etc.) is making a mistake....

come on, please... it seems excessive to me...

anyway, I would like one thing to be clear: any glue, if used incorrectly, is ineffective...

if in 100 years we find ourselves re-gluing a Ciresa rib, I will no longer be here but I doubt it will happen, we will have to use vinyl glue....

How do we use spirit varnishes on antique furniture, or in the re-polishing of historical soundboards....especially because removing the original varnish from an instrument is a crime...it's criminal....

but on new ones, polyurethane is used, sprayed even for the boards....

so? The important thing is, in any case, not to make those thick blobs of varnish as one often observes on poorly repaired instruments....because they are errors that impact the sound quality...