According to soundboard thickness and formula, mark how deep the bind bar goes.
The router jig is designed by David Hughes. Jude, the shop owner, marked where the router handle shall be on the plexiglass. Rout a little at a time so the wood won't chip.
Put soundboard in piano to check how well (or bad) the routing job is done. Adjust accordingly. Then sand the glue surface flush.
The bottom clamping jig is cut to accommodate the ribs. Check width of bindbar between top of bevel and soundboard edge, trim premade & over sized bindbar to width.
Glue on bindbar, clean glue squeeze-out thoroughly. Let dry at lease 1 hour before unclamping. Great demo by shop owner Mr. Jude Reveley.
Glue Bridge On Soundboard
The bridge location was triangulated before old soundboard was taken out of piano. Clamp new soundboard in, triangulate new bridge according to the old one. Trace bridge location.
Transfer rib line to the bridge mark using jig.
Pick 3 to 4 places where ribs meet bridge across bridge length, drill for locator pins. Install pins, transfer the mark to bridge bottom.
On bridge bottom, drill and dowel at the pin marks.
Look at the soundboard button location on old bridge both from top and bottom of the board. Use a thin bit, drill mark where to install new buttons, drill through the board.
Brush glue on bridge bottom, push dowels into locator holes where locator pins were, lock the bridge down. We use this go-bar type pressure device to fasten bridge to soundboard. Clean glue squeeze-out thoroughly.
The next day, glue is dried. According to the little drill marks we made, glue on soundboard buttons, fasten them down by screws on washers. When glue is dried in about 30 minutes, drill for and tap dowels in about 1mm into bridge bottom. trim and sand flush.
Yeah done for now. And there is a little button at the very treble side of the bridge. We'll later sand with 220 grid paper and spray with sealer then semi gloss finish.
Rib gluing and trimming
This process is surely not ideal. As a small shop, we do the best we can. This is a note of what's done now. Maybe next time we'll improve!
Each rib has two locator holes drilled with 1/4" bit, and locator installed. The locators make marks on soundboard. Make sure the board is pressed down everywhere so all locators transfer marks clearly. Then glue dowels in locator holes on ribs, and trim short.
Drill open the rib to soundboard marks with 1/4" bit. The jig makes sure drill bit goes down straights.
Ribs are pressed on by air pressure. Dry fit before applying glue just to be sure dowels go into locator holes and not too long. We have only limited amount of press, so glue one half at a time.
The next morning, unclamp everything, use jig to feather ribs. The power rotator plane is modified by the shop owner, two sides ride on jig, blade in the middle cuts wood. Steinway B has steps on feather. We shim the feather jig to different height to finish the steps. A cross bar is common on Bs as well. The shop owner routed the cross bar glue surface to let them be on same height.
Use a router and rounded bit to round sides on ribs. Looks much better afterwards.
A power sander would be much more efficient to smooth the feather surface. Soundboard is then put into kiln before further operation. Never forget to clean router bits with special cleaner to sustain their life ban.
We have an old Steinway B soundboard pattern made out of masonite. It will be trimmed and modified to fit the new Steinway B rebuild. Woo, the old pattern almost fit in the "new" B. Mark where to trim, sand it down with a belt sander. Ware a mask for that because of the very fine dust out of masonite and old epoxy.
Once the pattern fits in above the taped ribs, slightly smaller on size, smear a thick layer of wax on the tape and onto the side of outer rim. Fitting with ribs in makes sure that the pattern is exactly the size of soundboard that we'll trim later.
Mix up epoxy resin, hardener, and filler to the consistency of mayonnaise.
With the pattern pressed down under go bars, apply epoxy into gaps around the pattern. A syringe with a plastic tip works well here. The wax on tape and outer rim prevents epoxy from sticking onto rim and ribs.
The next morning, epoxy is dried. Take the pattern out of piano, sand around till flat. clamp pattern onto soundboard, make the first cut with a jigsaw, 1/8" away from the pattern. This step reduces workload on the router and operator. Set router bit bearing height to ride along edge of masonite, trim soundboard flush.
This method makes a well fitted soundboard. Worth the extra steps. The next will be mark and glue ribs to soundboard. Now everything will rest in kiln to keep the moisture content down at about 5% before the big gluing mess.
Plane Sharpening Practice
The 12-night hand tool class at Woodcraft has started. Following instruction from our wonderful teachers, the shop tools are going through trials and tribulations no matter they want it or not. Let's start from this Stanley plane.
This beautiful lady belonged to Tom Rourk, our piano technician friend who passed away last year. Hope he doesn't mind that I practice on her. The blade is so chewed up. Can't make it worse, maybe.
Pictures of plane taken partially apart to remind myself how to put it back together.
On a coarse sharpening stone, flatten the bottom blade surface. When lifting it to check, lift away from the honing edge so nothing is damaged. As a newbie, it took more than 2 hours to do this job. How long does it usually take for average woodworkers?
Here is an attempt to shape the bevel by hand on a wheeled honing guide. Didn't feel good and the bevel looks strange. Will try again when gaining more experience.
It is way easier to shape the bevel on Tormek, a water-cooled sharpening system. It is slow but does not heat up. When the bevel is shaped, 4 hours have already passed by, and it is not finished yet.
Now it is time to hone the bevel till very sharp. Feel that the bevel side is flat on honing stone, move steadily stroke by stroke, not to tilt over, until the cutting edge is shiny all the way across. A bur appears. Work on the flat side to get rid of the bur, then move on to finer stones till the blade is sharp enough to use.
Screw the chipbreaker tightly on the flat side of blade leaving 1/32" room, put this couple above lateral adjustment lever, then put the cap on tightly. Tom's old plane is ready to work now. So happy.
The process is put together from different pianos. And there must be some better ways to do this.
Remove screws on pinblock, drill out dowels with spade drill bit. This type of drill bits are pointy, won't slide everywhere.
Mark a line on both bass and treble, 3 inches away from case. This will be where we'll saw. Put a mirror on keybed, get a reading on stretcher thickness with a combo square, set it about 2mm over the actual thickness.
Set the router bit to match the stretcher thickness including the 2mm room so we won't cut into the stretcher. Route from under the stretcher. Safety classes shall be put on very tightly. Saw dust shoots everywhere.
Use sawzall to cut at the 3 inch mark on two ends. Hammer the pinblock off.
Chisel the rest of block off layer by layer. The shop owner uses power plane to remove the remainder thin layer of pinblock. To be safer, use a wet rag plus hot water or steam to soften glue, then chisel off the remaining thin layer.
Sizing Pinblock after drilling
This is for myself to remember the shop owner's instruction. Every shop works it differently. Hopefully we could learn more methods from rebuilder friends. The pinblock was fitted to the plate, marked and drilled. Now it is time to trim it to the original size.
On the old/original pinblock, two locator holes were drilled on bass and treble. A paper pattern was made for each side with pencil holes poked on locator holes.
The locator holes were drilled on the new pinblock. Put paper patterns on new block, align locator holes with tooth picks. Scratch the edge of paper with short lines. This will be the edge to cut off. Use a long ruler to connect two ends, mark with pencil. Note the bass edge has an angle. The angle was marked from old block with a line inward. Simply transfer/flip the angle to new block.
Get a reading on the angle from stretcher to keybed using both wixey and angle gage to be sure. Adjust the angle on bandsaw table to match it. The angle shall be as close as possible but don't sweat to make it exact. Draw a line on pinblock 1/8" out side of original edge. Saw on the outside line.
Adjust jointer fence to match stretcher angle, as well. Joint pinblock edge till the inside line/ original edge line just disapears.
Measure bass and treble edge angles with a protractor, adjust chop saw angle to match it. Chop right on or inside the marked line. The block is better a little shorter than the piano case at stretcher. It will allow adjustment from left to right when positioning the plate later on.