[CAUT] Ivory Tack

[reggaepass at aol.com]

All materials are different, wood, ivory, metals, etc... And they should be treated as being different. For instance, buff a capstan with tripoli buffing compound and then buff one with a buffing compound specifically formulated for brass, you will be shocked at the difference. Although some may say this is insignificant, it is not, there is a difference



Hi Mike,

And what IS the difference between the result from Tripoli  vs. "compound specifically formulated for brass" (which would be marketed under what name?)?

Thanks,

Alan Eder



-----Original Message-----
From: Mike Morvan <keymaestro at verizon.net>
To: caut ptg chatline <caut at ptg.org>
Sent: Wed, Dec 9, 2009 5:17 am
Subject: Re: [CAUT] Ivory Tack


  
Copied from a private post,
    How are you, long time no speak. I have been following the thread on ivory and have considered making a post but have not done so yet. 
So here it goes:
1. Yes we can replace individual 1 piece ivory keytops. 
 
    The reasons for the crack in the corners (notch area) of 1 piece keytops are many, and I'm not sure if I know them all but I'll list a few. For one, this is more likely to happen with new keysticks. New wooden keysticks, even properly dried down move more than 75 year old keysticks. Wood continues to shrink a bit as it ages and looses some of it's elasticity to a point. I would bet the mortgage that the preparation of new keyblanks is a fraction of what it was during the pre Great Depression era. Climate, our climate is much different here than in Germany where these keyboards in question were made. Fine furniture and other products made of natural materials should be made in an environment where the EMC is within 2% of it's destination environment. No chance of that happening with any imported or domestic piano. Ivory, the ivory itself is a natural material similar to wood and it needs to be properly dried down before it's application or it will shrink, distort, and sometimes crack. Glue, if the glue used does not allow the keytop and keystick to move independently with climate changes than things break. Something has to give and it's not going to be the keystick, it will be the thin ivory laminate. This crack in the corner happens on keyboards with plastic tops as well. There is a prominent Asian manufacturer that had this problem with their plastic covered keyboards as well. I believe it has been resolved.  And last but not least, sharp 90 degree corners are a source for stress concentration, if the notch had a small radius instead of a sharp 90 degree corner than the chance of it cracking there would be reduced, but again, using glue that is forgiving solves most of these problems.
 
2. Concerning the slippery feel of 1980's Kluge 1 piece ivory tops, I'm confused. Without seeing them and feeling them myself, I can only offer what I have learned in dealing with them in the past. The way that we prepare our new and vintage ivory leaves it a high gloss and initially it feels very smooth, but with a few hours of play the smoothness fades and the keys have the grip and texture that only ivory and bone are famous for. I've heard that some manufacturers use a "grain fill" or something to that effect which as you know from grain filling the pores of wood on piano cases, leaves them very smooth, perhaps forever smooth. We have restored many of the German 1 piece top ivory keyboards and never heard from the client with reference to them remaining smooth to the point that they can not be clearly distinguished from plastic. One time a client sent a Kluge keyboard here for recovering and he thought it was an off-white plastic when in fact it was an original 1 piece ivory keyboard with very little visible grain, they do seem to lack the traditional flame-point or fingerprint type pattern that we are used to here in the United States. We supply the new mineral plastics which are cool to the touch and grip your fingers a bit, but ultimately nothing plays like ivory or bone.
    The "pronounced" grain that someone spoke of could be the grain rising a bit. Ivory is a natural product similar to wood and has a lot of the same properties as wood, one of them being grain rise. If you wet an area wood it will swell and rise, same with ivory. The areas that are rising are more exposed (perhaps lost their finish) than the areas that are not rising, making them more susceptible to the effects of climate change. Lightly resurfacing the keytops and buffing will make them smooth and flat again.
 
I honestly do not know what was used to buff the German keytops originally, nor have I ever heard of a bees wax based buffing compound. I'm not saying it doesn't exist or doesn't work, I just have not heard of it. I would not use tripoli either, as someone mentioned, it's made for metals and is not a polishing compound but a cutting compound. All materials are different, wood, ivory, metals, etc... And they should be treated as being different. For instance, buff a capstan with tripoli buffing compound and then buff one with a buffing compound specifically formulated for brass, you will be shocked at the difference. Although some may say this is insignificant, it is not, there is a difference. If someone is playing horseshoes or hand grenades than close enough is close enough, we don't play that here. I've always been horrified by what I call "the supply house effect". Some people think that because a supply house markets something and assigns it a purpose than it is the right thing to use, in a lot of cases it couldn't be further from the truth. Buffing consists of two stages, cutting down and coloring. Cutting down prepares the surface and removes scratches, this could be considered the sanding of the ivory and preparing it for buffing; and coloring (a misleading term) removes the fine scratches and leaves a high luster. 
 
I don't know if this helps but good luck.  Happy Holidays, Mike
 
BLACKSTONE VALLEY PIANO
Michael A. Morvan
76 Sutton Street
Uxbridge, Ma 01569
(508) 278-9762
www.pianoandorgankeys.com
mike at pianoandorgankeys.com
www.thepianorebuilders.com

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