[pianotech] CA pinblock with tight bushings?

Douglas Gregg classicpianodoc at gmail.com
Tue Feb 15 11:22:11 MST 2011


Hi,
I was using water-thin CA glue. I get it from Rabidmodels.com. It is
true that thin CA glue can get thicker with age. To thin it again, you
can add a bit of acetone.   If you are wondering why I had problems
getting it past the bushing,  perhaps it was because I treated it once
without drilling. Also,  I was not breaking the seal around the pin
first by turning the pins. I did not want to upset a good tuning.
Sometimes the collars just seal up because of the capillary action
that traps some glue  around the collar and pin on the first
treatment. I think that the drilling method is superior because the
contact between the collar and  pin block is not that great. By
drilling first deep enough to put a needle about 1/2 the way down the
pin, you can be pretty sure of good wicking effect around the pin and
not running CA glue down the face of the pinblock under the plate.

I recommend using an 18 or  20 gauge needle 1 and 1/2 inches long with
a 3 cc syringe for good control. Since I am a veterinarian, getting
these is not a problem. For everyone else, I recommend getting needles
and syringes from www.smallparts.com.  They also sell 1/16 drill bits
that are 12 inches long if you are using a regular sized drill motor
and chuck. A 1/16 drill is 0.0625 in.  diameter. The 18 gauge needle
is 0.050 outside diameter.This is the closest size needle that fits,
as the 16 gauge is bigger than 1/16. Do be careful with the 18 gauge
as it might occassionally drip. They have number drills also at Small
Parts Inc. The number 65 drill bit is nearly a perfect fit for a 20
gauge needle, so not much glue will come back out of the hole while
injecting. No mess then. Sorry, I miss-spoke about using a #80 gauge
drill bit. It was a #65 drill bit with a 20 gauge needle after first
trying the 18 gauge in a 1/16 hole which was a bit messy.

 Small Parts Inc. also have lots of other interesting small hardware
and tool  that can be used with pianos or for making tools. I got
Titanium tubing from them and made my own tuning hammer that is really
nice. They have knobs for making jigs. They have all sorts of special
screws, exotic metal stock materials, spring wire, micro torches, rub
on letters, etc. It is a tremendous resource for the do-it-yourselfer.

Douglas Gregg
Classic Piano Doc


On Feb 14, 2011, at 7:30 PM, Douglas Gregg wrote:

> I have used the drilling method on a couple pianos with success. One
> was my own very old upright piano that I first treated by trying to
> wick the CA through the bushing. It did not get to the pinblock but
> sealed the bushing to the plate and pin and would not take more CA. ?

Hello Douglas,

I wonder if the CA you used was truly thin.
It's a real possibility all CA thins are not necessary alike.

I now exclusively use super glues from
Stewart-MacDonald
http://tinyurl.com/ybx5vyf


More information about the pianotech mailing list

This PTG archive page provided courtesy of Moy Piano Service, LLC