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I'm at my wits end with a very expensive replacement keyset I bought for my Steinert several years ago. The wood for the keysets was advertised as the same that is used on "expensive European pianos". There were many issues with the keyset, including faulty geometry, unfinished sharp edges on the Theran keytops, and more. After considerable post-purchase and installation expense and labor, the keyboard has been working for me, but is subject to what I believe is a recurring problem...

That problem is premature wear of the key bushings. My technician friend replaced ALL the keybushings at the front as well as the balance rail a little over 2 years ago. After just 1 year of my playing, 18 sharps were clicking when hit from the side. Rather than re-bush, we treated ALL the sharps with ProFelt, and... it improved things for close to 6 months.

Practicing the leaps at the end of the 2nd movement of the Schumann Fantasy yesterday, I discovered that... at least 2 of the sharps are clicking AGAIN!

I'd blame it on my playing, except that when I practice the same passages on my Konzert8, NO CLICKS - just a rock solid keyboard. I split my practice time about equally between the pianos, so it has certainly got wear on it as well.

So...my thought is to rebush the Steinert keys again, at least at the front pins, with leather - like Bechstein does.

If any of you have any insights/thoughts about using leather like this, I'd appreciate reading about them here or by DM. I also need a source where I can buy the leather.

And, before you ask, my technician used high quality felt of the right sizes when doing the re-bush (of a keyset not more than a year old!). The felt was high quality, and so was his installation work.

Thanks to the Piano World "Hive Mind".
Good Day to All.

A very important point in bushing keys with felt is one must "overbush" slightly to begin with, and after the glue and keys have dried for a couple of days sitting on the keyframe in the depressed position, then ironing them down to final size.

There is a specific tool for using a small soldering iron with a current controller to establish the proper temperature to use the ironing cauls to densify the felt.

The final sizing can be done with warm key easing pliers a couple days after that.

Properly done felt keybushings take a process spread over many days to get lasting, quality results.

Greetings,
I use felt for bushing. The quality is variable out there, some felt is far too soft, others are inconsistent. I use the best I can find, which seems to come from Pianotek, now days. I bush with cauls that are the same size as the pins, and I use a felt that is thick enough to provide sufficient compression when the cauls go it so that the cauls cannot be shaken out. After drying over night, I put one or two drops of VS-Profelt solution on the felt and reinsert cauls that are .001" larger. These I let dry for a full day, after which the cauls will just about fall out of the mortises.

The solution causes the felt to swell against the cauls, but when dry, the felt is no longer tight. It is denser, but it is also stable at a dimension that is .001" larger than the pin, so there is that clearance built in. I use hot hide glue to do this, so the wood will have expanded some. This procedure obviates the need for the sizing pliers and leaves me a very uniform key bushing. I don't like to use the pliers because what they crush is the wood fibers behind the felt and some of these pianos (in university settings) will need numerous rebushing over their lifetime.

The pins must be highly polished for a bushing job to last.
Regards,

Assuming that Ed M. Is referring to the Key Bushing Iron currently marketed by Pianotek, I am responsible for that little innovation. I was given the idea from Samuel Wolfenden's book: A Treatise on the Art of Pianoforte Construction", pages 114-115. I simply modernized it by figuring out compatible broach sizes, machined to fit a soldering pencil, and added a temperature modulator to make it usable.

Yes, this tool (used wisely) will effectively compress and smooth the cloth for better wear and less friction. Some like to add a small amount of powdered Teflon to the bushing as well. I like this too.

In my own rebushing (of course using the BUSHMASTER and ACCU-CAULS) I like to leave the cauls in as long as possible (days, if possible). I find I have a more stable result this way.

As to bushing with leather, there was some discussion on this forum about that some time ago. It is important to locate the right stuff and be capable of skiving it to the proper thickness. Much easier to work with brand new, consistent mortices over inconsistent pre-bushed ones, but doable with concentration. Shell Cordovan leather was what was recommended if memory serves.

Peter Grey Piano Doctor

Sorry...double post

Peter Grey Piano Doctor

My procedure is very similar to Ed Foote's. Remove bushings on day one, install new bushings on day two (tight fit), and and size with VS Profelt on day three. If I'm in a hurry, I can install the bushings in the morning and size them in the evening before bed and they will be ready the next day.

For your piano I would inspect the key pins very closely. If they have any kind of roughness to them at all the bushings will not last. I always polish key pins when rebushing keys.

Thanks, Bill, et al, for all your tips. As to the key pins, they don't seem to have any roughness to them. They were all replaced when the new keyset was manufactured to fit on the old keybed frame (sorry if that's not the correct term).

Will discuss options with my tech and go from there.

SO FRUSTRATED.

I've just re read your op.
Faulty geometry? Many issues?
Has the action been adjusted over and over to try and get it working properly? Could it be something really basic like, for instance, are the slots for the bushings parallel to the pins and in exactly the correct place in the key?
Nick

Causes could be:
- Poor quality bushing cloth
- Rough surface on the key pins - being new doesn't mean they are truly smooth and polished!
- Insufficient cloth depth in the key mortice

I'm not thinking of much else that might be causing front bushings to become loose so fast. I'd be interested in photos of the bushings - could there be some kind of lubricant that is causing the felt to become compacted rather than worn out? I have seen that before.

As to the leather question, they cause much more friction when used at the front rail. They last extremely well, but would need to be lubricated regularly in order to play any kind of glissando!

I despise leather key bushings. So many problems to list.

I do wonder if ecsaine would work better.

Peter thank you for the key bushing iron!!!! I love it.

I also heat my key easing pliers and almost never use them to crush the wood.

It is best to let keys fully dry over several days before final sizing with heat alone. It is possible to crank the job out, but problems happen then!!!

Ed, looking here https://www.ecsaine.com/en/function/, your idea seems brilliant to me. At this point, I think I'll look into doing a few sharps with it as a test.

Clicking Problem Solved! (at least for now).

First, I just wanted to thank those of you who chimed in with your expertise and your suggestions. I really appreciate your willingness to help without monetary compensation.

Regarding the details of the problem and the fix, while things are fresh in my mind - I just reinstalled the action after putting the stack back on and did some test playing - I will take you through how I figured out what the problem was, and how my technician friend fixed it for me.

As can be seen in the thread, I originally posted a question based on identifying premature bushing wear as the root cause of a clicking problem with some sharps on my keyboard. This was after less than 2 years of wear on bushings made from PianoTek's bushing cloth, installed by a technician who has done HUNDREDS of keyboards in his 47 years in the trade.

So... at my instigation, we went chasing after leather, and ecosaine. He had some ecosaine; we tried it on 4 sharps. It seemed to solve the problem on 2, but there were still 2 clickers remaining.

WHAT COULD BE CAUSING THOSE CLICKS?

We kept going down the same holes (literally), looking at the inner surfaces, checking the quality of the gluing, and... NOTHING.

Today - I tried something different. My technician had suggested turning a front rail pin as a way to make the key fit snugly enough to stop the clicks (yes, probably not best practice, but worth a shot as a diagnostic). So, prior to adjusting the front rail pin on one of the offending sharps, I removed the two naturals around it, then hit the key from the side again, and... NO CLICKING NOISE.

Hmmmm.

So I put the naturals back around the sharp, tried hitting it again, and CLICK CLICK.

Light bulb goes on over my head: It isn't the bushing that's the problem. The sharp is rubbing against the adjacent natural all the time, clicking when hit forcefully!

And, that, dear readers, turned out to be the root cause for not just the 4 sharps on which we were focused, but something like 90% of the naturals. There were clear scuff marks up in the area near the key-weights.

The fix: hand filing the naturals for a better fit + a bit of front rail pin adjusting.

FWIW - my technician told me in unequivocal terms that this is the first keyboard in 47 years of rebuilding and refurbishing actions to exhibit this particular problem, and he attributed it to a lack of precision in the fabrication of the keysticks - CNC machine or not. This problem is one more thing I can add to the list of errors that were made in that fabrication job. It also, to my way of thinking, shows the value of fine manual craftsmanship COMBINED with powerful automation tools. We believe that some "hand finishing" should have been done at fabrication time since the fabricator had the keyframe and many of the original keysticks. I can also state, without equivocation, that the original keysticks did not have that problem. Not after 80+ years of wear.

BTW - I just thought of an analogous situation from a different discipline - dentistry. I recently had a crown made for one of my molar teeth. In the past, dentists would make a wax impression of the tooth and send that to the crown fabricator. Now - a 3D image is taken with some sort of laser gizmo, the image is viewed, enlarged, on a computer screen, verified, then sent to the fabricator who reproduces EXACTLY what was sent in the specification. HOWEVER - there is still "hand work" to be done. Once the crown had been installed, my dentist had me bite down on "bite paper" which leaves a mark on the tooth from where that tooth has been struck by the opposing tooth (kind of like a sharp hitting up against a natural...). The final part of the work is for the dentist to file down the crown surface until no marks are shown. So... this is a combination of state of the art automation with fine craftsmanship.

Nattered on more than enough.

Live and learn.

Good Day to All, and thanks again.

That makes a lot more sense than loose enough keybushings to allow a key to slap into it's neighbor. There must be clearance clarence!