Pinblock Fit

[Newton Hunt]

>  delamination amongst all the others."  Say what?

Sorry Folks, foggy brain, lame leg, tired body, glazed mind;
take your pick.

The reasons for doing a pinblock fit as best you can are
multiple but consider these:
	The integration of the block into the main structure of the
rim and stretcher provides structural stability leading to
tuning stability.
	Fitting the block to the flange of the plate provide
support from the pull of the strings and tuning stability.
	Having tight screws all around the plate and rim provide
structural stability and tuning stability.
	Properly drilled and and strung blocks provide tuning
stability provided the coils are tight and the right height
above the plate; no more than 1/8" .
	Block boring angle should be set to the string leaves the
tuning pin at 90 degrees when the bottom coil is 1/8" above
the plate.  This prevents coiling climbing over each other
or prevents them from moving down the tuning pin.
	
There are many other issues like soundboard and bridges but
I will leave those along here.

My piano, a 1920s Ivors & Pond 5'3" massively constructed
piano with a plate as heavy as a S&S B plate had a very
poorly fit block.  Whether from bad fitting or shrinkage
(poor curing) there is a 1/16"+ gap all across the flange
and every lamination is separated at some point or other. 
Positioning the plate is critical and since I got the piano
dismantled I will have to work backwards for a proper fit. 
No big deal in this case; screw old block onto plate, drill
3/16" hole through plate and block, secure old block in
case, measure from holes to rim and stretcher, fine fit new
block to plate and drill through plate into block, position
new block in case and measure from holes to rim and
stretcher, cut as needed then secure the block to stretcher
and rasten with screws and epoxy.

EXCEPT the old block was tapered in thickness so; before
securing block the plate has to be dropped in the block
pulled up to the plate and bearing checked and if needful
wedges cut to fit the block to the rim.  Interesting little
problem, yes?

I have ordered height adjustable plate rim bolts from Jim
Coleman Jr. so I can adjust plate height without removing
the plate, a major advantage since the piano is in my small
dining room.  More interesting problem, the dog ate a damper
top flange, what to do, what to do.  I have top flanges from
a different piano that fit, almost but I will need to trim
off the bottom of the lever to get the sos. tab to match in
height, about 3/16".

Another interesting problem is that this piano has no
agraffes at all and a string pattern was not taken before
destringing and since the plate is out on the enclosed (but
not sealed) porch the old string marks have corroded over. 
SO, hammer marks will be made on a secured clear plastic
sheet so when the new hammers are installed they can be
angled, burned traveled and spaced to the old string marks. 
I also have the newly rebushed damper guide rails to act as
a preliminary string spacing guide.  Refinements will have
to be done with much care later.

Metal parts will be cleaned with a wire wheel, the plate
will be sprayed (on the porch) and the bearing bars will be
polished then I will need lots of help getting the plate
into the house and in the piano, a hook into the ceiling and
a come-along used to raise and lower the plate the few times
I will need.

Sitting and having a set of goals, determine the problems,
work out a possible set of solutions to each problem as you
see it, be flexible, measure multiple times before cutting
($pinblock is $125) and take your time and di it right.

There are more than just good reasons most of the better
piano makers integrate the block, rim and stretcher into a
cohesive whole.  Stability, endurance, pride and skill.

Now, aren't you sorry you asked?

Have a good weekend coming up.

		Newton