At 05:34 PM 01/09/2001 -0500, you wrote:
Thanks for getting the installation procedure started, I would like
to add a few of my own tips for avoiding some of the pitfalls.
This would be great if we can get an outline for the ultimate installation
running.
At least we're not talking about a Chickering Quarter Grand.
>Pinblocks are not that mysterious, just tedious and detail oriented.
Once you get the hang of them they are relatively easy.
>First take every conceivable measurement you can. String
>heights, bearing all over, plate height, plate location from
>stretcher and rim and block height.
>
>Think through this, beginning to end, write down the
>procedure as you perceive it and add to that or rearrange it
>as you think it through. Have a plan, work the plan and
>change it as you learn more.
That's why it is best to learn on a lesser brand, no one will care
so much about any mistakes :-)
>Next drill two small (3-4/32") holes through the plate and
5/64" is sufficient, not too big, not too small. 2 or 3, inconspicuous
>into the old pinblock. One in the bass and one in the
>treble. These holes are your main orientation from this
>point on. Carefully measure, after plate removal, the
>distance from the center of the holes to the rim and to the
>stretcher and write them down on the keybed.
Better yet, as Wally Brooks conveyed: With these two or three registering holes
drilled in each the bass and treble sections make templates. Drill the holes in
inconspicuous places, under the strings, between pins, centered between screw
holes. Once the plate is removed, clean the build-up from the corners.
Place the edge of a sheet of suitable paper against the stretcher. Place a
straight
edge along the case side and cut the paper pattern with a razor blade
creating a cut
parallel to the side (if there is no room for the straight edge along the
side, place the
paper on the side and the straight edge on the stretcher). This contours
the paper to
the angles of the case. With the paper flush to the case on two sides,
punch the register
holes with the same size bit. This will index the side and front on your
new block.
>Carefully measure the thickness of the block material.
>Order the new block and have it thickness planed to you
>dimensions by the supplier, unless you have a thickness
>planer.
>
>Precision cutting will be needed here on. Layout the
>primary cut, the shape of the plate edge but remember, that
>cut is at a three to five degree angle so you must account
>for this plus the fitting removal of material. Here you
>need a band saw. Tilt the table at the proper angle and
>make a test cut and match it to the cut you need to make on
>the block.
Make the block oversized to start.
>You will need an air driven grinder/sander with 40 or 50
>grit disks. Home Depot or similar have these items. Get
>the disks made for this tool, don't cut your own.
>
>Paint the plate (your choice of chalk, graphite, or other)
>and lay the block into plate and MARK it's location. Hit it
>will a rubber mallet so you have marks and grind off the
>marks until you get a nice fit, top to bottom left to right.
Usually the horn at the tenor break indexes the block. Lacking this
projection you need to draw a line across the plate and block to
maintain left to right positioning. Little things you need to know.
>Clamp it in place and drill the holes through the plate and
>into the new block.
Drilling the register holes at this point can lead to a
mis-registering
if the new screw holes are not perfectly drilled in the center
later on.
Once the block is fit to the plate, clamp it in place and drill all screw
holes.
Use a tapered #18 bit for wood screws with a shoulder and a straight bit
for screws
threaded-to-the-head. I prefer new nickel plated, threaded-to-the-head
screws to avoid
metal fatigue of the old ones.
Install all screws, drill register holes. Installing all screws taps the
holes so final installation
is not difficult which can lead to a screw driver skipping across a newly
refinished plate.
Little things like breaking screws and chipping finishes you need to avoid.
KWYADAWYADI.
An optional method before drilling the register holes at this point is to
remove the block
and lay a bead of epoxy on the flange and clamp it back in place and
reinstall one third of
the screws. This will lock the plate in place with no further chances for
becoming askew.
Drill the register holes and fill the register holes on the plate with some
of the leftover epoxy.
Or don't fill if the plate is not being refinished.
The tuning pin holes can be center-punched at this point.
Once the epoxy has cured, remove the block, position the patterns with a
few drill bits and
trace the perimeter of the block. Connect the bass and treble pattern
markings with a straight
edge. Cut on a band saw leaving a trace of pencil mark for a joiner or
similar tool to remove
for final fitting.
Fit to case, fit with case/plate. You are ready to drill the tuning pin
holes on a drill press.
>Lay out the lines, and angles, on the new block from the
>holes. at the band saw cut the width and length of the
>block and fit it into the piano. Finish the fit with a
>power planer or a good power sander. Double, and triple
>check everything.
>
>At this point you need to decide if you are going to bore
>the block in or out of the piano. If in then just glue it
>in and mount the plate.
Make certain the top was fitted and there is no bow in the block before
gluing in place.
Otherwise glue to the stretcher with the plate installed.
>If out then you need to put the block onto the plate with three or four
>screws and center
>punch each pin hole and the other screw holes. Use a red or
>blue pen to mark the screw holes so you know what to bore
>for. The angle o f the bore is determined by measuring the
>angle to the plate where the string goes from 1/8" off the
>plate to the riser or aliquot bar, between 2 and 5 degrees.
>What you want is the string coming off the pin perpendicular
>to the pin when the bottom coil is 0.125". Very simple and
>uncomplicated.
>You should use a cut off piece of pinblock and bore holes of
>different sizes, F, G, 17/64" and pins from the set you will
>use, mic those and write the sizes on the block. Drive in
>the pins and use a torque wrench to torque each pin and
>write that on the block of wood. Allow to lay around as
>long as you can and check the torque as often as you can.
>Pick the bit size you like for the pin you like and go and
>buy five of those bits, all from the same manufacturer, the
>same lot, and change the bit every 50 holes or so. Feed
>speed is important; fast drilling makes a smaller hole and
>slow feed makes a larger hole. Feed speed is critical for
>best feel.
>
>Mic all the pins and arrange them in order, fat ones in the
>bass and skinny ones in the treble. Just don't touch the
>threads with sweaty or greasy fingers.
>
>The rest of the work you should be familiar with. If not
>scream here.
>--
> Newton Hunt
> Highland Park, NJ
> mailto:nhunt@jagat.com
Knowing different ways of doing things will help to perfect your own method.
Practice makes perfect. There is always Beginner's Luck. But in the words of
Harry Callahan, "Do you feel lucky?"
Regards,
Jon Page, piano technician
Harwich Port, Cape Cod, Mass.
mailto:jonpage@mediaone.net
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