pianotech: CA repairs

[Dean May]

>>What I dont really get is how you appy the accelerator, if you spritz it
all over the board and ribs how does the glue get penetration?

I spray the accelerator along the top surface of the rib, and around the rim
wherever I can reach. I have in the past actually put it into a hypo oiler
so I could be more directional with putting it on the joint only, but it
isn't necessary. By spraying much of the accelerator goes places you don't
need it to go. But no harm, it just wastes some accelerator. If you wait 15
or so seconds before applying the glue, the glue won't set up right away,
giving it time to penetrate the joint. 

>>I was thinking, with the piano on its side, to put accelerator on the
bottom joint of the ribs and apply glue from the top, it will run down hill
along the length of the rib.

Yes, that is the way the glue runs. In doing so it runs through the
accelerator I have sprayed on, then into the joint. The accelerator doesn't
have to get into the joint. It just needs to be on top for the glue to
contact it before the glue runs into the joint. If you see the glue going
into the joint and not just running along the top, you know there is a void
there. Give it some extra glue and accelerator to fill it up.

If you observe glue running all the way through and coming out the bottom of
the rib then you need to spray accelerator on the bottom of the joint to set
the glue up there and form a dam. 

>>Its easy to get glue to the straight side rim but how do you apply it
along the belly rail and the bent side?

I've already said how to do this, but it sounds too fantastic to be true. Do
the bent side first while your glue bottle is full. Holding the bottle
vertically aim the tip at the bent side rim joint and squeeze- squirt the
glue vertically at the joint. The capillary action of the glue will actually
suck it vertically up into the joint. Remember it is not the force of the
squirt pushing it into the joint. You just need to get the glue there and
the capillary action takes over. 

The rim joint on a grand can often also be done from the topside without
turning it on the straight side. Just run some glue down around the
perimeter of the soundboard. The capillary action will pull it on into the
joint. 

The belly rail usually gets plenty of glue from the excess that runs down
the ribs. But if you feel it needs a little more, point the tip of your
bottle in that direction and squirt. 

Don't forget to do the bridge to soundboard joints, as well as any bass
apron joints. You don't need to turn the piano up for this either. Just run
a bead of CA along the joint. If there is a void the capillary action will
pull it in. 

One more thing: after applying all the glue while the piano is on its side,
be sure to spritz accelerator over everywhere you glued and wait for a
minute. You want to make sure all the CA is set up before you set the piano
upright. Otherwise it will drip down onto the carpet. DAMHIK

Be sure to tell us how it went. And don't hesitate to ask if you have any
more questions.


Dean

Dean May             cell 812.239.3359 

PianoRebuilders.com   812.235.5272 

Terre Haute IN  47802


-----Original Message-----
From: Dave Doremus [mailto:algiers_piano at bellsouth.net] 
Sent: Monday, June 18, 2007 11:42 AM
To: deanmay at pianorebuilders.com
Subject: pianotech: CA repairs

Hi Dean, Ive been reading your CA rib advice and have an Erard with
mysterious noises and no detecabe seperations I d like to try it on. What I
dont really get is how you appy the accelerator, if you spritz it all over
the board and ribs how does the glue get penetration? I was thinking, with
the piano on its side, to put accelerator on the bottom joint of the ribs
and apply glue from the top, it will run down hill along the length of the
rib. Its easy to get glue to the straight side rim but how do you apply it
along the belly rail and the bent side? Thanks for your help, I hope this is
not an imposition.

Dave

Algiers Piano Works
New Orleans