On the afternoon before this piano was going to be moved back to her school, I was putting all parts together. The fallboard didn't want to lift all the way up. It turned out that we raised the key height too high according to the new action design. The felt on bottom of fallboard was rubbing on key tops. About a week before leaving the shop, the piano shall be put together to make sure nothing goes wrong at the last minute.
This is the first time I install a Renner backaction by myself following instruction from shop owner Mr. Jude Reveley.
This plate receives new hitch pins. With a nail punch like this, the old pins are punched out from underneath. Pay attention not to enlarge the holes.
This is another ongoing tribute, in my life, to Piano Technology mentor Mr. David Betts and Ms. Debbie Cyr.
At the piano shop, the owner prefers DMT diamond stones. They are heavy and solid. I work with his set the best I can but found that the course stone looses its grit very quickly, and quickly it becomes close to "fine". Recommended by fine woodworker Mr. John Cameron located in Gloucester, MA, I bought a set of water stone. They work much better, not loosing grit. The stone brand and price vary greatly. So far, this set of Naniwa water stone from Sharpeningsupplies is working well. The preparation takes about an hour yet it is essential for a good stringing job without much damage on the piano case. First, the top surface is covered by blankets and cardboards for protection. The little rings to fasten blankets are chopped from PVC pipes.
The plate is ready to be sanded down and refinished. Before sanding, the agraffes are removed. I noticed while taking them out, it felt very tight to them turn up. There might be adhesive applied by the last rebuilder who may had a very hard time dealing with these little thingies. This piano has one agraffe insert and a large size (1/4") agraffe as repair from before. The rest are 7/32" in size. Oh, there is also a long-ago broken agraffe possibly from over tightening. The bottom part of that broken one is still in the hole. How to get it out? Hmmm. There are 3 way I have learned:
1. Put the top piece back on, use friction to turn the bottom up since brass is soft and can be easy to turn up. 2. Tap a sharp slotted screw driver in, then turn it out while hammering it down. 3. Drill through the bottom part with a small bit, increase the bit size and drill until a thin layer of brass is left inside the screw hole. The thin piece can then be easily chipped out. 4. Easy-out or screw extractor. Drill a hole for the size of the easy-out, tap in the extraction bit, turn it counter clock wise by hand to extract the broken brass bottom. This is the last solution. Easy-out can do big damage. This operation is documented on two pianos, a Steinway L and a Steinway O. Work is guided by shop owner Mr. Jude Reveley at Absolute Piano Restoration. Before working on bridge, the plate is clamped at ideal position. Normally 2 clamps are enough. The pinblock is being glued down under plate, thus many clamps here.
This is the first time setting downbaring on a whole piano after graduation from North Bennet Street School, seven years ago. While doing this, lots of old memories came back. Where has Mr. David Betts gone? Must be somewhere he can enjoy fishing, golf, fixing stuff, eating carrot cakes, have 6 things of butter with one corn muffin, etc.
The procedure is instructed by our shop owner Mr. Jude Reveley. I had doubts during this practice. At least it is documented for friends and myself. On each section between struts, there will be one sample note on bridge grinded to ideal height. Then the plate can be taken off and whole bridge planed to height. Many thanks to our shop owner Mr. Jude Reveley for the instructions and letting me practice. The soundboard is refinished with sanding sealer and top coat. Here we use polyurethane for sealer and acrylic urethane for top coat. Both sides of the soundboard are sprayed with sanding sealer, then only bottom gets top coat. The bridge side will be sprayed with final coat after bridge top is milled to ideal height, notched, and bridge pins installed.
One each rib, mark two places on the ends to install 1/4" diameter soundboard locator pins (shown in the mid picture). Drill with a 1/4" bit on the mark as deep as the locator pin goes.
Place raw shaped soundboard on top of piano, make sure it covers the entire inner rim and belly. Trace on the bottom of board along the outer rim, mark where belly line is with some dots. Then flip board over, place on a work surface, connect the belly line dots (shown in picture on the right). Clamp board down on work bench.
The raw ribs are made longer than needed for adjustments. Place each rib at place, mark how much to saw off. The marked line is parallel with eighter rim or belly line. Trim conservatively, a little at a time, better leaving too long than too short.
This working process was instructed by the shop owner Mr. Jude Reveley. The shop owner designed the species, length, width, radius, etc. of the new ribs on the Steinway L being rebuilt. We are going to have the ribs made today. According to the data sheet, pick the wood - Sugar Pine for rib # 1, Sitka Spruce for rib # 2-11. Discard wood that has flaws, such as splits and knots. When selecting wood, make sure each rib is at least 2mm taller, 4mm wider, and 10cm longer than spect. The ribs will sit on soundboard with grain vertically placed. All ribs are quarter sawn.
There are quite a bit of wood residue left on inner rim after soundboard removal. We can use either sanding or teaming method to clean the inner rim surface. Use sanding when inside of outer rim is not going to be refinished. Use steam if it is going to be stripped and refinished. The first step of either method is to chisel the wood residue as clean as possible, leaving minimum amount of wood to be sanded or steamed off.
The tail of piano was cracked due to environment and released tension after strings were taken off. The shop owner suggested using of WoodEpox to fill the crack. Before filling, the bottom board, where the tail leg is attached, is taken off. The filling was done on day one, then sanded on day two when it is completely dried. Note: leave the filling higher than the surface because it will shrink when it dries. Turn vacuum on while sanding WoodEpox. It is very powdery, possibly bad for the lung, possibly very bad.
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October 2024
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