[pianotech] CA Glue and Tuning Pins

[Mark Purney]

Lee,

A respirator is a recommended, as is ventilation, if possible. Of 
course, you will need to warn the client about the fumes. They don't 
last long, but they are very harsh, and if you are up close to the work 
without a respirator, they can be very harmful to you. Never use cotton 
cloth with CA glue. It can ignite on contact with the glue.

Have acetone standing by for any cleanup or glued-finger emergencies, 
but be careful so you won't need it. Get the thinnest CA glue you can 
find. Many technicians use medical syringes, and I've tried them with 
about 5 different gauges of needles, and I find that it's hard to 
control the amount you are dispensing. I've found that the standard 
hypo-oiler bottles with the screw cap with the built-in needles are 
superior. Unless you can burn the glue out of the needle afterward, the 
oiler bottle is pretty much disposable, as the needle will clog. To load 
the bottle, compress it, dip the needle into the container of CA, and 
let the suction fill the bottle partially. You can also take off the 
needle cap and pour the glue directly in to the oiler bottle, but you 
run a higher risk of spilling that way.

Tilt the piano on it's back (upright). For grands, remove the action and 
put newspaper down on the keybed in case any CA drips down through the 
bottoms of the holes. Apply a healthy amount to where you can see it 
pool around the entire circumference of the base of the tuning pin, but 
not enough to where it runs on to the plate. Start with the pins you 
normally tune first, and proceed as you would on a tuning. Repeat for 
all pins to be treated. Wait a few minutes, and tilt the piano back up, 
and the pins you started with should now be tight enough to hold a 
tuning, unless the pinblock damage is too severe for CA to work.

Once you start applying the glue, you'll find that it goes pretty 
quickly. But you may want to set aside an hour for your first job, and 
decide from there what pace you want to set. I'm sure there are some who 
can do an entire piano in about 20 minutes. I set aside about 45 minutes 
so I don't feel rushed. But when working with CA, never allow a time 
constraint to interfere with being careful. CA can have disastrous 
results if you are not careful with it.

If I missed something important, someone else will surely point it out. :)

Good luck,
Mark




On 7/5/2011 12:17 PM, lee innocent wrote:
> Hello All,
> I am considering CAing an upright piano, I have never tried this 
> method before, always repinned.
> What I would like to know is:
> 1.  Is this a permanent fix for loose pins
> 2.  What is the best method for a thorough job
> 3.  How much time should I allocate
> Thanks in advance
> Lee