On my grand [Estonia 168 - Oct. 2008] since about a month you hear faint clicks when operating nearly all keys, audibale at soft slow playing in general.

The best way to demonstrate the phenonemon is by gently/slowly depressing any key up to the point of let-off - as if one would check the let-off setting. Just prior to the escape you hear the faint click. When you repeat the procedure immediately on the same key, the click disappears! Leave that key for a while and try again, and there is the click again!

Any idea what might cause those clicks.

This started after the last tuning. No special additional regulation work was done apart from adjusting the hammer line on some keys that were out of range but not on all keys.

Many thanks,

schwammerl.

Oh my! I know exactly what the problem is. The dreaded rep spring clicks.
I'll let Dave chime in on this. He has also dealt with this in a new Bechstein. I've dealt with this when my Bosendorfer was new, and also on a few Seilers, and Schimmels. There are a few suggested solutions. They only work 40% of the time. The manufacturers are also puzzled. Renner doesn't have an anwser.
I know this has been a particular problem with some runs of Renner wippens with the standard butterfly repetition springs during the years from 2003 to 2007.
It has been discussed here in the tech forum. Try a search.

Could also be a simple loose screw below hammer rest bar, which you can fix. Kawais do that now & then. A check you can do from top, looking into strings, probably 4 points you can see and tighten screw. May or may not solve but worth a check! SM

I would agree with Curry on this one: repetition spring clicking in the groove, aka "grub." I've seen so many pianos with this condition, that I've begun to view it as a maintenance issue rather than a manufacturing problem.

Most of the time, applying a lubricant like ProTek MPL 1 to the spring at the place where it contacts the lever will solve the problem, but it will probably come back at some point. It doesn't take long to fix, but it's sort of amazing to me that I see pianos that are 50-60-70 years old that have not yet developed this noise, while 1-2-3 year old pianos come down with it routinely.

I've also been hearing the same sound in damper lever springs, which can cause squeaky notes and really annoying squeaks when operating the sustain pedal.

I 3rd what Curry and Dave said.... Although a bit uncouth perhaps, short or replacement, I've been known to do something like using a small sharp bladed knife in a cupped motion to give it a new spot in which to rest the spring in the slot. I don't remove much stuff. I do it in sort of a brushing motion in a curving fashion, to take a tad bit off from where the spring engages the wippen. It seems to work. I haven't had problems so far with (KNOCK ON WOOD pardon the pun, I couldn't resist it!) with the noise returning but, it hasn't been all that long since I tried it either. Maybe a year or a little longer? Maybe it's just the top layer that is causing the clicking noises? I don't know....

I'm a bit surprised that manufacturers and technicians cannot really pin-point this problem.

Would it not be possible to remove the action and actually see the clicking part move? My intuition tells me that if a part clicks audibly, the movement causing the click should be sufficiently large to be seen at close range. And if you can see it, you should be able to trace it and fix it - not so?

When the tension increases on the rep spring prior to let-off the coil of the spring is shifting/ moving around causing the click against itself.

Not so Mark. The area in which the spring slides in the grub is miniscule. I've had the wippens out and was able to recreate the clicks while examining.
What Jerry said works sometimes, mostly it doesn't and the clicks return. Lubing the grub works but 90% of the time the clicks return shorly after. Removing the old DAG from the grub and re-burnishing and re-daging sometimes works but the clicks mostly return. Another solution is to disengage the spring from the grub and push the coil of the spring closer together where it bushed to the post of the wippen body. There was a PTG Journal article on the a while back. It will work if that is where the clicking is coming from but not if the clicking is coming from the spring sliding in the grub.
I've had a few european sources tell me that there were two issues to blame but Renner denies both. The first being the metal used for the springs was not proper(contaminated)and could cause the clicking. It was also stated that Renner was using a chinese supplier for the springs at the time. This one I don't believe and Renner also denies. The second was that a few runs of the wippens were manufactured with the grain orientation of the wood in the wrong position which is causing the clicking. This seems somewhat plausible but who knows.

curry,

Whether true or not I had the same problem with my W&L 161 that I previously owned. When at the first tuning the tech examined the action he said he could hardly distinguish it form a Renner action.
So apparently the Chinese copied the Renner action so well they even copied the Renner oddities!

schwammerl.

Very interesting Curry. Thanks for the explanation. Nice to know that what I tried probably won't last either so I don't waste a lot of time on that method either then.

Cheap springs could make sense. I wonder (do you suppose) if because these are possibly, crappy springs that they are weaker than normal or some of them (probably not) have tiny fractures in them creating the clicking? You know when a pedal spring like a pelican pedal spring is cracked a little bit, it moves and clicks? That's where I'm coming from.. Maybe?

Mark, there are many problems in pianos that are no so easy to find and fix. Clicks, rattles and buzzes are the most difficult of almost anything to locate. While many problems appear to be caused from one location, we often find the source of the problem 10 feet away in a curio cabinet.

Curry, I'm trying to understand your post, and need to ask: what is meant by "DAG" and "re-daging"?

DAG is a product used by action manufacturers to provide a lubricating film on friction areas of action parts such as the jack toe, jack top, the grub and top surface of the rep lever which is the surface area where the hammer shank knuckle rests. It is also used on bridge tops. It is essentially graphite in an alcohol suspension.

Mark:

You should ask what the grub is. Say a friend wants to know or something...

DAGS are also in the back of the piano to hold the action in place during moving... Yea, they're all over DAGnabit.

My DAG wags his tail when I feed him his grub

The only absolutely permanent solution I have come up with for this is to pop the springs out of their grooves, slip a length of appropriately sized PTFE heat-shrinkable tubing over the ends of the springs, heat-shrink the stuff around the wire with a heat gun, put the springs back in their grooves and re-regulate them.

Provides a smoother lift and speeds up the action a bit as well. Though not enough to warrant doing the whole operation for that reason alone.

ddf

Curry,

I have this friend (on old sea-dog turned piano tuner, would you believe), and when I discussed this thread with him, he said I should ask you what the grub is.

Not sure what (or why) he wants to know, but anyhow:

What's the grub?

I thought Bob just "splained" that? He "Splained a DAG" too.

Mark:

Actually I am a tuner turned sea dog turned electrician/tuner.

My dog used to have two grubs and a wippen. Now he only has a wippen, lol.
On a more serious note. Many older grands from various manufacturers used to have a thin piece of some type of bushing cloth in each grub. I assume to overcome this very problem from ever occuring.

I have to admit, I had not heard the term "grub" before - I've always heard it referred to as the repetition spring slot.

I looked up "grub" in Piano Parts and Their Functions and it was interesting that the only mention of "grub" is to the space in a wooden flange between the ears. They call this the "Grub-out".


However I think "Grub" is kinda catchy and certainly less of a mouthful than "repetition spring slot"!

It'll be on the market soon. Grub-out, the all out eliminator. It'll erase everything. When you're done using this magnificent tool, you'll not only need a magnifying glass to see the grubs but, all you'll have left is a wippen without the whippen minus the whip. A nice clean writing utensil....

Curry, I'm still laughing at that one! So, his wippen, is now just wippen in the wind. Next, you'll have to have him re-pinned.

I'm "sucking hind-tit" here at the "tail" end...

I have a question, I have a similar problem with my action, some keys have a soft squeak when the key is depressed slowly, when the double escape mechanism lifts the hammer after that you hear a faint squeak, my tech showed my that the spring rubs in to this small cut in the wood, that is where the sound comes from, he lubed it and it was solved.
Some have returned and I lubed them again but I do not feel like doing this over and over.... why do some keys have this issue and other not?
What product would be advices in europe to keep it lubed??
My piano is from 2005

Please advice.
Thanks

Although I'm an amateur, allow me to add a thought here, based partially on Arthur Reblitz's book (which I consulted on this issue last night), and partially on information from an Austrian piano builder who worked at Bösendorfer:

It is probably useful to clean the spring (perhaps even polish it) and also the slot (whether it be felted or plain wood) before trying to lube (or re-lube) it.

In the case of my Ibach's damper springs and their felts, they are running absolutely smoothly and silently after I cleaned both the springs and the felts (no lube was added until now). In my experience, washing benzine, similar to white spirits but more volatile i.e. less persistent, is very effective in removing old, sticky lubricant. A drop or two on a rag or cotton bud is all that's required.

My $0.02...

Hi mark,

Thanks for the tip.
It seems logical, it is only some keys that make the squeek, all the others are fine without lube....