The five layered pinblock stock is made here at the shop. Chickering pinblock is in two pieces, while most of the blocks are in one whole piece. First step, make sure it is thick enough comparing to the original one. The shop owner, Jude Reveley, traces shape and chops the pinblock into two pieces.
On a band saw, adjust the table according to the surface angle on the original pinblock. Then saw the new piece on the line traced in the last step.
This pinblock (PB) has a step. The shop owner cuts a piece out of the old PB, double taped it to the new PB, then routed that step with a router, bearing against the old PB piece.
The plate is flipped upside down. Apply graphite on contact surface. Place new pinblock, check fitting, rub it against the graphite to make marks. Also check if the wood is rocking on the plate.
The marked spots show where the wood is contacting the plate, we call them high spots. Sand the high spots down, so the rest of the wood gets closer to the plate surface. Then mark again, sand, check. After a few hours of this, the marks are all over the wood which means the fitting is good (never enough tough depends how much time you are given). According to the shape of the PB slot on the plate, the smaller piece is fitted first and clamped down to be a locater for the larger piece.
Same procedure, rub and mark, and sand down high spots till the graphite marks are all over the wood. Also check from down under to make sure PB surface is just against the plate without any gap.
For the best PB to plate fitting, the shop owner prefers to smear epoxy on the edge of PB and clamp it down tightly till epoxy dries, usually over night.
On the next day, flip the plate around, clamp the new PB to place, mark for tuning pins with a transfer punch that fits tightly into the tuning pin holes. Remove PB, sand off rough edges.
Coat the PB surface with a layer of finish to protect the surface from moisture. Let dry, usually about 2 hours. Then drill for tuning pins. The PB to plate screw holes are still not marked yet. This is the first Chickering pinblock I've worked on. It is screwed to the plate from the bottom. Will see how the shop owner prefers to do the screw holes. We shall see.
We are using WNG perimeter bolts instead of the original ones. First, make sure the plate is at the original/accurate location. Mark for the bolts with transfer punch. Drill for the bolt body. Drilling with the plate in is to double secure the hole location just incase the drill bit slips.
Here are the WNG perimeter bolts. The long bottoms go under plate. They can be screwed up and down to adjust plate height. The short tops are to lock down the plate. We cut a notch on the tip of each bolt and wax it for easy installation. The notch functions as a tap.
All the bottom parts are punched down now. We use are pressure instead of elbow grease. Is it cheating?
Next, modify the plate where perimeter bolts go in. The WNG bolts are flat with washers. The original counter sinks on plate need to be filled for the washers. Before filling, chase them with 1/2" drill bit for the new 1/2"ish bolts.
Wax 1/2" dowels, insert into bolt holes, maybe put tape on the bottom. then fill counter sinks with epoxy. Let dry over night.
The next morning, epoxy is dried. Sand flush by hand or machine. The middle picture shows a flat WNG bolt and washer. Now it'll fit much better on top of plate. Next, the plate can be sanded, sprayed with gold, and installed.
Steinway & Sons, Model S, using sitka spruce.
Select wood of similar color, cut to length, about 2" longer than soundboard pattern on two ends of each piece of wood. Plane wood 1mm thicker than final thickness. The final thickness is based on the original board or requirements from piano rebuilders who ordered the board. Before machining, mark both sides of each board with pencil or chock. The machine will take off the marks. No marks left means no low spots missed.
Put the wood pieces in order, check warping. The warps shall go down, same with soundboard crown. If the wood is warping upwards (left), flip it over (right).
Check if a nod is at a visible location (left). If possible, switch to where it'll be under the plate (right). Check that the switch won't affect the final shape as a whole piece.
On each piece, rout tongue (left) on one side and groove (mid) on the other side. All tongues are facing the same direction, so are grooves. The work scene will be very messy (right). It's ok, as we kept telling ourselves.
Put all pieces together, check untight joints. Oops, there is a gap (left). Re-rout the non-flat edge, check again and again. Last fitting check, see if the whole piece is still bigger than pattern. If smaller, add wood. Trace the shape of the pattern (mid), mark the end of each piece, that will be where we stop applying glue (right).
Locate clamps of different length where they fit. Mark location of clamps (left). Measure length of board where the clamps are (mid), select cauls accordingly (right). The cauls will be on top and bottom of soundboard, in between the clamps.
Ready to glue. Place tarp under clamps to catch glue (left). Dry fit before gluing up. Apply glue between the marks we just did where the neighboring pieces end (right).
All clamped up. Check gaps again, make sure the clamps are tight (left). Clean glue squeeze outs so it will be easier to sand after glue dries. We'll wait for a couple days before unclamping this big boy/girl.