Steinway B WD-40 update

[Tom Servinsky]

List,
To refresh your memory, I was dealing with a Steinway B which was sprayed with WD-40 by the owner. The visible signs of the WD-40 were mainly in the belly area, as one could write his/her name through the gooh build-up. A little was in the tuning pin area.
Initially the sustain had always been pretty good, but after the spray, the sustain diminished to about 4 seconds in the mid tenor. The bass was no better. My initial prediction  was that the WD-40 ruined the soundboard and we would have had to start over. Keep in mind that there was excellent bearing and crown throughout.

So here's what I discovered:
Before teardown I had experimented with replacing a few strings throughout the piano to see if the strings were the culprit. Some improvement in tonal clarity and sustain, but not enough to be convinced that was the smoking gun.
Thoroughly cleaned the termination points ( capo/ agraffe and bridge pins/ cap)- on the same strings. Some improvement but not that much.
Replaced bridge pins to the next size with the same length on the same notes. Some tonal improve somewhat.

My gut feeling was thinking that the build up of gooh on the soundboard  had to be the reason for the sustain issue.

After teardown:
Did my usual "thump" test on the board to check for sustain.  Surprisingly pretty nice, full sustainable sound. The board definitely was still very excitable.
Checked the bridges to see if WD 40 had ruined the bridge cap. Some of the list's suggestions were aimed at dealing with the quality of the termination points. Overall, the bridge cap was pretty decent, however I did have some softer wood in the very top section.
Checked the bridge pins- VIOLA! Here was the smoking gun. The bridge pins were so loose that I could take them out by hand. Additionally the depth for the hole was much deeper than the pin length. Replaced the pins up to a #8 x 1" in the treble bridge and to a #9 x1" in the bass bridge. Epoxy was added to the very high treble for additional pin support.

The soundboard was thoroughly cleaned with mineral spirits, then stripped, then refinished. The piano has been restrung and sustain is back to where it once was. Sustain the tenor is now 18 seconds. 

What I discovered: 
Good solid termination must exist at the bridge pin/string intersection. Pins must very secure and bottomed out for maximum termination. Note that when I had replaced the pins on my initial experiments, I didn't use an appropriate length for the bridge pin. Although it was tight, it was not deep enough for maximum effect.
Adding a lubricant to the bridge pin area can potentially destroy any chance for capturing energy from the string.
Bridge caps are generally free of any finish,  thus the bridge is particularly more vulnerable to lubricants like WD-40 soaking into the wood.
WD-40, unlike many other lubricants that we use, has a goohy build up factor. Avoid this product at all cost.
It is understandable why adding this type of lubricant is more suitable for home related squeaks and groans than acoustical instruments.

Tom Servinsky
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