Kawai RX3 Hammer Recommendation

[Regi Hedahl]

My customer recently purchased a 2003 Kawai RX3. He originally planned on purchasing a Shigeru Kawai SK3 but ended up purchasing the RX3 instead because of the substantial savings. With the savings, he has some money left over to upgrade this piano. Another piano technician highly recommended Abel hammers and WNG shanks & flanges for this piano. I am a fan of Ronsen hammers and have pretty much used that brand exclusively. However, I have never installed hammers on a Kawai so I'm not sure what kind of results I would get. The last hammer installation I did was on 1987 Baldwin SF10. I installed Ronsen Bacon felt hammers and got very good results with no voicing. Would I see similar results on a Kawai using Ronsen hammers?

Regi

[Joseph Garrett]

Regi,
short answer: I don't think so. Of course the major question is: what type of tonal difference are you seeking.
Personally, I'd install Kawai hammers on that piano. The RX series, imo, has a nice robust tonal pallet that is pretty much in your face w/o being obnoxious. The Kawai pianos are highly engineered and well thought out imo. Unless you are trying to make it sound like something else, go with what is known to work. (Kawai) BTW, I consider the Kawai hammer unique among hammers. They are made different and, I suspect, for a good reason.<G>
Best,
Joe


Captain of the Tool Police
Squares R I
gpianoworks.com

[Fred Schwartz]

Regi,

 

Joe is correct, the RX hammers are really well suited to the piano, but the main problem is that they require a lot of needling when first installed.  So they will be bright, but can be voiced to a pretty wide range of tones according to what the customer wants.

 

I have installed Ronsen Wurzen hammers in RX grands with good effect, and also Abel naturals.  The range of tone (mellow when soft, bright when loud) is not quite as wide as with well voiced Kawai hammers, but in some circumstances that might be what is needed so it’s fine.

 

The key to any hammer you install in pianos is how you voice them.  I feel that hoping to install hammers without doing voicing is not a wise approach – no hammer has the best sound if just installed and regulated.  There will be a much wider tonal pallet if you work with them some after installation.   For example, some years back a technician installed new Abel concert hammers in a Kawai EX concert piano without doing the full voicing prep and hammer shoulder needling.  The piano sounded really poor, and the school that owned it started complaining to Kawai that there was a problem with this piano, it couldn’t be used any more!  So I was sent to work on it and spent a good solid 12 or 13 hours pulling it back into shape – and everything was OK.  But the piano still isn’t quite up to it’s potential.

 

I would not change the shanks to carbon fiber.  Kawai tested this basic design many years back and decided to stay with hornbeam because the sound fit our scales and piano designs better than the carbon shanks.

 

My final thought is, are you and your customer sure you need to change the hammers?  I am suspecting that, if you do not like to needle hammers, perhaps you should try that first anyway.  Needle them using Kawai’s techniques to get a warmer sound, reshape them, refit them to the strings, then decide if new hammers are really needed.  If they aren’t worn too thin the RX pianos have very voiceable hammers.  There is a Kawai voicing guide in the Tech Support area of our web site – if you haven’t seen it before, download and read through the voicing guide.   It is in the “Acoustic Downloads” area.

 

http://www.kawaius-tsd.com/index.html

 

Don Mannino

Sent from Mail for Windows 10

 

From: Regi Hedahl
Sent: Friday, August 11, 2017 5:54 AM
To: pianotech
Subject: [pianotech] Kawai RX3 Hammer Recommendation

 

My customer recently purchased a 2003 Kawai RX3.  He originally planned on purchasing a Shigeru Kawai SK3 but ended up purchasing the RX3 instead because of the substantial savings.  With the savings, he has some money left over to upgrade this piano.  Another piano technician highly recommended Abel hammers and WNG shanks & flanges for this piano.  I am a fan of Ronsen hammers and have pretty much used that brand exclusively.  However, I have never installed hammers on a Kawai so I'm not sure what kind of results I would get.  The last hammer installation I did was on 1987 Baldwin SF10.  I installed Ronsen Bacon felt hammers and got very good results with no voicing.  Would I see similar results on a Kawai using Ronsen hammers?

 

Regi

 

[Regi Hedahl]

Since my last post, I finally got a chance to visit and tune this piano. It was bought sight unseen but it appears like it was a piano that got virtually no use since new; tight key bushings, close letoff, no hammer indentations, no scratches, no wear on pedal, etc. However, the piano is voiced extremely mellow and is located in a smaller room with hard floors. I service some similar RX3's for a school district and they are not even close to this mellow. I never saw these pianos when they were new so I don't have a point of reference. As the piano is now, it is too mellow for the customers taste (as well as mine) and I'm not sure if it'll brighten up considerably over time or if I need to do some type of intervention to brighten it up. I'm kind of thinking that it was voiced this way for the previous customer and therefore, the rather low price the customer paid.

Regi

[Dan Dannenfelser]

Hi, Regi,

Perhaps start with a very light filing of the existing hammers, and have them listen to it for a few weeks, and see if they start to perk up. That should tell you if there's hope for them.

Best of luck

Daniel F. Dannenfelser,
Registered Piano Technician
(916) 224-0122
www.dannenfelserpiano.com

[Joseph Garrett]

Captain of the Tool Police
Squares R I
gpianoworks.com


-----Original Message-----
>From: Regi Hedahl <piano...@gmail.com>
>Sent: Aug 23, 2017 11:29 AM
>To: pianotech <pian...@googlegroups.com>

[Joseph Garrett]

Regi,
Oops, I hit send before typing! My bad.
I'd try a hot hammer iron first and see what that will bring. (almost hot enough to scorch, but not quite.) The Kawai hammer is a unique critter and is very voiceable imo. Even beating on the strike surface of each hammer will bring it up. (support the tails!)<G>
Best,
Joe

[Joseph Garrett]

A quick individual strip sand with 800 to 1000 sandpaper strips will suffice, some times. I watched Don Mannino do it on an atrocious hotel lobby piano, at a convention. It was a very nice transformation, imo. I wouldn't wait a couple of weeks, but just proceed until desired crispness is achieved imo. because it's too soft, you have all kinds of options. (Lacquer is the very, very, very last option imo.)

Best,
Joe

Captain of the Tool Police
Squares R I
gpianoworks.com


-----Original Message-----

>From: 'Dan Dannenfelser' via pianotech <pian...@googlegroups.com>
>Sent: Aug 23, 2017 11:34 AM
>To: pian...@googlegroups.com
>Subject: Re: [pianotech] Kawai RX3 Hammer Recommendation
>
>Hi, Regi,
>
>Perhaps start with a very light filing of the existing hammers, and have them listen to it for a few weeks, and see if they start to perk up. That should tell you if there's hope for them.
>
>Best of luck
>
>Daniel F. Dannenfelser,
>Registered Piano Technician
>(916) 224-0122
>www.dannenfelserpiano.com
>
>> On Aug 23, 2017, at 11:29 AM, Regi Hedahl <piano...@gmail.com> wrote:
>>

[Regi Hedahl]

Joe,

I am familiar with both procedures and will give it a try on this set of hammers. It'll be very interesting to see the outcome because these hammers have a long ways to go.

Also, how about tapering these hammers to take some weight off of them? That would lighten up the action some and bring out some brilliance.

Regi

[Joseph Garrett]

>
>Also, how about tapering these hammers to take some weight off of them? That would lighten up the action some and bring out some brilliance.
>
>Regi

Hmmm? Why would tapering the hammers make them more brilliant? Unless you are generating a whole lot of heat in that process, I doubt that you would get any "brilliance" from that procedure. Reducing mass will make the attack sound better because of less time the hammer is spending on the string(s).
If the action is "heavy", which the RX series does not have, in my experience, I'd look elsewhere before reducing mass in relation to touch. If it is heavy, I'd suspect there's a friction problem or just simply poor regulation.
BTW, Take care of the action condition and the regulation BEFORE committing to "voicing" anything. That's the best advice I can offer,
Best,
Joe

[Fred Schwartz]

Regi,

 

Ah, that’s better news than needing to change the hammers!  The piano most likely was softened by someone wanting it mellow, and if they got the core of the hammer soft using steam or a liquid of some kind it will be hard to get a nice singing tone from the piano again.  If the softening didn’t go too deep under the strike point, then you should be able to get the tone back up.

 

Yes, strip file the hammers, and finish with the finest grit paper you have to get the surface smooth and get rid of tufts and such. A slightly pointed shape usually works best, so put extra pressure on the upper shoulders to slightly flatten that area, then go over the top with fine paper – I use 1,000 grit with a lot of pressure and speed.

 

Don’t neglect the action regulation. Bed the keyframe, straighten the hammers on the shanks (heat the shanks), space hammers to strings carefully.  Get the letoff and drop up like it should be, and check your hammer blow.  If the hammers are sounding better after filing, fit them to the strings nicely and then give the piano a good hard tuning.

 

If the hammers have been softened too much right under the strike point, then lacquer them.  Normally Kawai doesn’t put any hardener in our hammers, but must needs and all that.

 

Enjoy!  It will be a nice feeling to get a nice singing tone out of the piano again!

 

Don Mannino

(Kawai traveling tuner)

Kawa...@live.com

 

Sent from Mail for Windows 10

 

From: Regi Hedahl
Sent: Wednesday, August 23, 2017 11:29 AM
To: pianotech

[Jon Page]

It might be wise to apply a hardening agent to the sides of the hammers under the strike point rather than letting it soak in from the outer edge. Stand the action on its side and apply to each area above the core. Flip the action and apply to the other side. The high treble would require application from the outer surface, unless there is a lot of felt over the core.

[Regi Hedahl]

Follow up:
These hammers responded very well to heat. I used a small clothes iron and turned up the heat to the point just below scorching the hammers. I applied heat to the strike point and down the shoulders. Afterwards, I worked up to 500 grit sandpaper. It made a dramatic difference and I would say the brilliance is very similar to the new Kawai RX3's that I have come across. Overall, I am highly impressed with this piano. The action feels very good and it has excellent tone.

Regi

[Joseph Garrett]

Nanner Nanner. Told ya so.<G>
Best,
joe

Captain of the Tool Police
Squares R I
gpianoworks.com


-----Original Message-----