Falconwood Pinblock Problems

[Ron Nossaman]

>I have contracted a reputable rebuilder to do the soundboard work, new
>pinblock and restring two Steinways and an M&H. I have found the pins to be
>very draggy and jumpy in the Steinways (both M's), not so bad in the M&H A.
>Of course the Steinways have the most high profile use. Fine tuning them is
>very difficult.
>
>The installer assures me to "wait a year and they will dry out. You will
>think them as the best pinblock you can use." What happens before a year
>passes can be politcally damaging with the patrons.
>
>Any experiences out there? Or should I just install my own hardrock maple
>pinblocks?
>
>Thanks for any input. Happy Holidaze!
>
>Lorlin Barber, RPT
>
>

Years ago, looking for a better alternative to low quality rotary cut
pinblock material, I bummed a scrap of Falconwood from another tech and did
some experimentation. I concluded that it was too unforgiving for my taste
and ultimately settled on Delignit but I learned a few things that apply to
both.

I found that pressed or rolled thread tuning pins were unsuited to blocks
this dense. Besides being too erratic in size from pin to pin (as much as
.005") the surface finish of the threads was much too smooth and resulted in
a very snappy, jumpy pin. In fact, there is a commercially available bird
call based on the principal of a smooth (tapered) metal pin jammed into a
piece of maple. When it is turned, it chirps! Cut thread pins, of more
uniform size, proved to work best. What seems to be happening is this. The
"tooth" of the cut threads fills up with wood dust scraped from the side of
the hole during installation and chipping. This acts as a buffer between the
steel pin and the hard block and gives you a nice friction gradient when the
pin is turned so it doesn't pop and move all at once but, rather, moves at
different times at different levels as the torque overcomes friction at any
given depth. Rosen dusted on the pins and into the holes does the same thing
for the same reason. Rosen doesn't seem to increase torque, but it
definately does smooth the torque progression down the pin when it's turned.
I haven't used a pin driving fluid, but I suspect that roughly the same
thing is happening there.

I double-drill the block using first a 1/4" bit to remove the bulk of the
stock and generate most of the heat on the first pass where it matters
least. Then I re-drill with a 6.8mm (.2677) for 2/0 pins. Cut thread pins
installed with rosen then produce a good tight uniform feel throughout the
block.

I like the results of this procedure a lot, and I don't see why it wouldn't
work just as well with Falconwood. The double drilling trick seems to make a
big difference in uniformity. It also seems to make drill feed speed much
less critical with less chance of burning and glazing the hole.

Ps: Cut thread tuning pins don't "chew up" your pin block when turned simply
because there is no place for the dust to go to escape the teeth. The piano
salesmen with the hankerchief demos are WRONG!

Sorry about the message length, but a windbag by any other name...
 Ron Nossaman