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#1162146 - 03/13/09 12:23 AM Attn Rebuilders: Pounding in machine  
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Supply Offline
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Rebuilders -
I have been thinking about developing and building a simple pounding in machine. It would really be advantageous for a shop to have a machine that pounds every key about 20-30,000 times after regulation and first voicing, to stabilize the tuning, bring action and key felts to the state of compression they will eventually attain, pound in the voicing etc. Then fine regulate, tune and voice and you can send the piano out to the client and not have to worry about major changes in the first months of playing.

This is what factories do, and it makes real sense. Would there be a market for such a machine? What would it be worth to a rebuilding shop?


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#1162150 - 03/13/09 12:28 AM Re: Attn Rebuilders: Pounding in machine [Re: Supply]  
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I've been thinking of making my own. Mason & Hamlin has a nice machine based on a series of cams. Never gotten around to it to this point. I figure it would take me about two days of labor to build once I get the design on paper. Parts wouldn't be that big an expense. So it would have to cost less than the two days labor it would take to build myself????


Dale Fox
Registered Piano Technician
Remanufacturing/Rebuilding
#1162153 - 03/13/09 12:50 AM Re: Attn Rebuilders: Pounding in machine [Re: Dale Fox]  
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I use a Playola that works great. I have a disk I play at night that pounds in the notes for 10 hours.
What I like is it also plays music during the day.
I have over 5000 songs on disks.

I paid $1,500 for a used one and felt it was worth every bit of that.


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#1162174 - 03/13/09 02:44 AM Re: Attn Rebuilders: Pounding in machine [Re: Rod Verhnjak]  
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I've thought about it for years! It's a great idea Jurgen.

Rod - do they still make Playolas?


Ryan Sowers,
Pianova Piano Service
Olympia, WA
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#1162196 - 03/13/09 05:46 AM Re: Attn Rebuilders: Pounding in machine [Re: rysowers]  
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Okay, it´s not the same like a machine, but it helps to work all new felts (excepted the hammer felts)and leather with a hammer. Just pounding them with a hammer on the work bench.

Gregor


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Münster, Germany
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#1162212 - 03/13/09 08:03 AM Re: Attn Rebuilders: Pounding in machine [Re: Gregor]  
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Just bring your niece's and nephews under the age of five over, they always like to pound on mine when they visit.... grin ha


Les Koltvedt
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#1162216 - 03/13/09 08:24 AM Re: Attn Rebuilders: Pounding in machine [Re: Les Koltvedt]  
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Anybody have a picture of one that piano manufactures use? All I can think of is that scene from Barbarella!


Jeff Deutschle
Part-Time Tuner
Who taught the first chicken how to peck?
#1162277 - 03/13/09 11:14 AM Re: Attn Rebuilders: Pounding in machine [Re: UnrightTooner]  
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Sign me up..

Sally


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#1162327 - 03/13/09 01:23 PM Re: Attn Rebuilders: Pounding in machine [Re: S. Phillips]  
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piano tech - tuner - dealer
Münster, Germany
www.weldert.de
#1162333 - 03/13/09 01:38 PM Re: Attn Rebuilders: Pounding in machine [Re: Gregor]  
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Thanks, Gregor!

Hey everyone, there is a model of an upright action with a true repetition lever on that site!


Jeff Deutschle
Part-Time Tuner
Who taught the first chicken how to peck?
#1162340 - 03/13/09 01:46 PM Re: Attn Rebuilders: Pounding in machine [Re: UnrightTooner]  
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Here's the model mentioned by Jeff:

[Linked Image]

Do you think that action could be troublesome?

Last edited by Erus; 03/13/09 01:49 PM.
#1162400 - 03/13/09 04:32 PM Re: Attn Rebuilders: Pounding in machine [Re: Supply]  
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Originally Posted by Supply
Rebuilders -
This is what factories do, and it makes real sense. Would there be a market for such a machine? What would it be worth to a rebuilding shop?


I think so. I've been using one for about 15 years now.

ddf


Delwin D Fandrich
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#1162429 - 03/13/09 05:37 PM Re: Attn Rebuilders: Pounding in machine [Re: Del]  
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accordeur Online content
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Unright or Erus,

You should really start a new thread with that action model. To me, it looks like it would be difficult to regulate, especially drop and let-off. I think the Fandrich action is simpler, easier to regulate and more elegant.


Jean Poulin

Musician, Tuner and Technician

www.actionpiano.ca
#1162485 - 03/13/09 08:36 PM Re: Attn Rebuilders: Pounding in machine [Re: rysowers]  
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Originally Posted by rysowers


Rod - do they still make Playolas?


Yep, PianoDisc makes them. Way to much money for what we need them for.

Last edited by Rod Verhnjak; 03/13/09 08:37 PM.

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#1162488 - 03/13/09 08:49 PM Re: Attn Rebuilders: Pounding in machine [Re: Rod Verhnjak]  
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Originally Posted by Rod Verhnjak
Originally Posted by rysowers


Rod - do they still make Playolas?


Yep, PianoDisc makes them. Way to much money for what we need them for.


They do?

ddf


Delwin D Fandrich
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(To contact me privately please use this e-mail address.)

Stupidity is a rare condition, ignorance is a common choice. --Anon
#1162505 - 03/13/09 10:05 PM Re: Attn Rebuilders: Pounding in machine [Re: Del]  
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I believe it was a QRS product, not Pianodisc. I don't see it on the website currently.


Roy Peters, RPT
Cincinnati, Ohio
www.cincypiano.com
#1162536 - 03/13/09 11:28 PM Re: Attn Rebuilders: Pounding in machine [Re: RoyP]  
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Last edited by Rod Verhnjak; 03/13/09 11:30 PM.

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#1162578 - 03/14/09 01:29 AM Re: Attn Rebuilders: Pounding in machine [Re: Rod Verhnjak]  
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Yeah, $4200 is a chunk of change. You could hire a lot of child labor for that amount.


Ryan Sowers,
Pianova Piano Service
Olympia, WA
www.pianova.net
#1162585 - 03/14/09 01:50 AM Re: Attn Rebuilders: Pounding in machine [Re: rysowers]  
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This one is for sale on ebay. Still $3,000.00

[Linked Image]

[Linked Image]


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#1163049 - 03/15/09 08:42 AM Re: Attn Rebuilders: Pounding in machine [Re: Supply]  
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Jurgen, I'm certainly interested, but don't go into production for me! I am getting started at rebuilding, and expect to be full time when I retire from my current job in about 5 years. Anyway I'd think every rebuilder needs one. Priorities and money are the thing. I'd think that you need to come in at less than $1000 - $1500. More than that and this inventive crowd will probably be in the DIY camp. Just my guess.


- Duane McGuire
www.mcguirepiano.com

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#1165080 - 03/19/09 02:16 AM Re: Attn Rebuilders: Pounding in machine [Re: Duane McGuire]  
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Yes, I was thinking in that ball park.

If it is the floor model I visualize, it will need to have a certain amount of mass to keep it stable. Which means that shipping cost could stifle the sales potential for the machine.

Perhaps just produce blueprints for techs to build the machine or have it built for them locally?

#1165088 - 03/19/09 02:28 AM Re: Attn Rebuilders: Pounding in machine [Re: Supply]  
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Sorry my good friend but before you get into business.

You mean like this?

[Linked Image]

When built it looks like this.

[Linked Image]

And Sounds like this.

http://www.youtube.com/watch?v=2a_uTTMT30A&feature=player_embedded


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#1165099 - 03/19/09 03:08 AM Re: Attn Rebuilders: Pounding in machine [Re: Supply]  
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Originally Posted by Supply
Yes, I was thinking in that ball park.

If it is the floor model I visualize, it will need to have a certain amount of mass to keep it stable. Which means that shipping cost could stifle the sales potential for the machine.

Perhaps just produce blueprints for techs to build the machine or have it built for them locally?
Or leave a shelf or box that could be filled with sand or rocks.

Personally, I am not interested. If a part sticks, it will stick when it is pounded, so it will not wear in anyway.


Semipro Tech
#1165360 - 03/19/09 03:08 PM Re: Attn Rebuilders: Pounding in machine [Re: BDB]  
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Originally Posted by BDB
.. If a part sticks, it will stick when it is pounded, so it will not wear in anyway.


It has nothing to do with sticking parts. If parts are sticking, your repair and regulation is incomplete. Finish doing that work before you hit the switch of the pounding machine.

Pounding machines are used to play all keys vigorously, usually about 20,000 times or so, after which a final regulation, voicing and of course tuning takes place. This will result in a piano that is much, much more stable in tuning, touch, and voicing after delivery.

I see that Rod has found a source for such a machine that I was not aware of. Thanks Rod!

#1165375 - 03/19/09 03:37 PM Re: Attn Rebuilders: Pounding in machine [Re: Rod Verhnjak]  
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Quote
And Sounds like this.


Pounder refrain

Kind of catchy. Reminds me of...

Never mind
grin


Steinway 1905 model A, rebuild started 2008, completed 2012
Yahama CVP-401
Will somone get my wife off the Steinway so I can play it!
#2017676 - 01/20/13 06:28 AM Re: Attn Rebuilders: Pounding in machine [Re: Supply]  
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Hi! I´like to revive this post because Im restoring about 20 pianos for an institute, and after replace all felt and bulkskin from the action i have to regulate again about a month of use, but they don´t play all the keys and the compression on the felt is not even. Who wants to wait and regulate over and over

I have draw some ideas of a 2 lever pouding machine like the one on the video but to be place on top of the piano to avoid that big box. I haven´t build nothing yet,

I´ll love a electronic one with solenoids but still to expensive and more living in mexico, I have talk to a WN&G tech and they have design a pounder over the pianodisk system, the hardest part is to hold down the solenoids up side down with springs.

The playola is too old and for the price, the lx system is far less expensive than that and better,

Who has more ideas, pictures or drawings of your machines? I guess most if not all restorers should have one on the shop.

someone here has an old (but not to old) un-used pianodisk system or parts sitting around the shop getting dusty I´ll be interested

I´ll apreciate your comment

Thanks




Sergio L. Ruiz Jones
Piano Tech
Pianos & Pianos
Piano tuning, service and restoration
Afinacion y Restauracion de pianos
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Sergio.ruiz@pianosandpianos.com
Mazatlan, Mexico.
#2017735 - 01/20/13 10:08 AM Re: Attn Rebuilders: Pounding in machine [Re: Supply]  
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I learned to pound with 2 hand pounders, then a regulation pass is necessary. And earplugs
Keyboards are stabilized with a long lever that push on the underside of the pinblock and an adapted woodblock above the balance (als used to lower a key that is only a little high) balance punchings where ironed before installation, also , it does not make them so even but it helps.

Using first grade paper punching is also a must. The ones sold by Yamaha are good, not too sensitive to moisture and rigid enough.

The machine pounding is more efficient for the hammers and the action, but hand pounding can be firm , also on a new stringed piano you have to tune hard 4 times and that pound also , regulation passes and voicing are inserted between those tunings. I will pass the exact procedure.

So I always have think I need a machine, but can live without it.
I believe the machine pound not so hard, also , I asked how many strokes and had no precise answer, but even 10000 have been said to me too much.

Do someone know an exact range ?



Ps felted blocks in wood (leaded) are placed on the strings to avoid too much noise , it also make the pounding more efficient. (not anyone agree on this, but the noise is really too much, I also dont like to pound strong on bass strings)

Last edited by Kamin; 01/20/13 10:35 AM.

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#2018356 - 01/21/13 12:57 PM Re: Attn Rebuilders: Pounding in machine [Re: Supply]  
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The idea of the pounder is to effectively and quickly put the equivalent of 10, 20 or more hours of playing onto the new or re-built piano. In factories, this noisy process is done in sound insulated rooms. It seems they want the strings to resonate freely.
At two blows per second, a pounder can rack up 10,000 keystrokes for every key in short order (extended lunch break!).
This would be hard to beat pounding by hand.

#2018404 - 01/21/13 02:15 PM Re: Attn Rebuilders: Pounding in machine [Re: Supply]  
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Sure Jurgen , at 7200 impact one hour, I dont compete...

Then :

I hit several times before regulation to check the jack alignment

Then after finishing regulation I do the first tuning with tough strike

After that I do the damper works – then a second tuning with hard strike

Then second regulation and pre-toning, after that a third tough tuning

After that the finish regulation, finish damper regulation and finish voicing.

Now if you have counted well – the amount is a little less than 10000 …..

The reason is that regulation stability comes with time and in the correct relation between strike power to strike amount.

Too much is not automatically better.

( I am just jealous wink
 



Last edited by Kamin; 01/21/13 04:34 PM.

Professional of the profession.
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#2018441 - 01/21/13 03:06 PM Re: Attn Rebuilders: Pounding in machine [Re: Olek]  
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Originally Posted by Kamin
...Too much is not automatically better.

( I am just jalous wink

...but not enough is automatically worse!... I kind of wish I had a pounder too...

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