adhesive for ivories

[MICHAEL MORVAN]

Alan,
    You're right, perhaps I should clarify. Use the glues best suited to the 
materials being bonded, ivory/bone to wood, or plastic to wood and the glue 
best suited to the situation, in a clients home or in the shop. Hot hide 
glue and a clear drying industrial pva are by far the best glues for natural 
materials. Pvc-e and eva have good characteristics for bonding non-porous 
materials to porous materials. Spray painting the keystick with white paint 
clogs the pores in the wood and leads to a poor glue joint especially when 
coupled with ca glue.
----- Original Message ----- 
From: "Alan Barnard" <tune4u@earthlink.net>
To: "Pianotech" <pianotech@ptg.org>
Sent: Thursday, January 05, 2006 3:38 PM
Subject: Re: adhesive for ivories


> Having said all that, what are you recommending? Only wafers, even for
> incidental repairs?
>
> I, like many others apparently, have had good success with the PVC-E.
>
> On another note (A B-flat, perhaps), when I have had thin, very white
> ivories to replace, I have not been above spray painting the wood white
> before applying glue and ivory. Anybody else do that?
>
> Alan Barnard
> Salem, Missouri
>
>
>> [Original Message]
>> From: MICHAEL MORVAN <keymaestro@verizon.net>
>> To: Pianotech <pianotech@ptg.org>
>> Date: 01/05/2006 2:29:54 PM
>> Subject: Re: adhesive for ivories
>>
>> Water based glues/adhesives will curl natural products, in this case
> ivory.
>> To counter this effect slightly wet the top off the ivory with water and
>> you'll find less warping takes place. If the underside of the ivory still
>> has the wafer attached, then you are not gluing ivory to wood, you are
>> gluing glue to glue, with another glue (what remains on the ivory and the
>> key). Compatibility of glues is a factor. Ivory is translucent, so what
> one
>> does with glue will show through (repairs etc..). The linen wafer is what
>> makes ivory appear white. Titanium dioxide helps only a little at best.
>> Titanium dioxide mixed with glue remains in suspension, it does not
> dissolve
>> in the glue, so when it is clamped nearly all the glue (and whitening) is
>> squeezed out leaving a tan ivory appearance not the desired "white"
>> appearance. Pvc-e glue is not a wood glue. Wood, bone and ivory are
> natural
>> materials and should be bonded with a glue made to glue "natural
> materials"
>> together.  Pvc-e glue has very poor strength, creep and rigidity
> resistance.
>> Pvc-e glue works well for plastic to wood in the case of plastic keytops.
>> Plastic is not a natural material and is not affected by environmental
>> changes that much, when wood moves with environmental changes you need a
>> glue that remains gummy and offers very little resistance. If the top
> can't
>> move with the key it will break. Ivory and bone are natural materials and
>> move together, plus the joint between the head and tail acts as a
> built-in
>> expansion joint. When applying one-piece ivory tops you must use a glue
> with
>> less creep and rigidity resistance or it will crack between the head and
>> tail.
>>
>
>
> _______________________________________________
> pianotech list info: https://www.moypiano.com/resources/#archives
>