Wood!

Just got the soundboard wood from Switzerland today. (Quite a fun time getting it here: shipping was about $400, plus duty; and had to clear the wood through customs at the airport.) But it's here, and it sounds super nice when you tap on it. It's the same wood that Stradivarius used to make his violins. It's harvested by a small company in the mountains after the full moon, around midnight, then flown down the mountain by helicopter and quartersawn and air dried.

Making the Rose: Wax Carving

Here's a pic of the new rose wax positive...

Leg Carving 1B

I decided I'm most likely going to replace the first leg I carved for a few reasons: 1. I didn't rough it out finely enough, so the edges are too wavy; 2. I made it too deep, so the bases of the raised elements stand out and are ugly; 3. overall I'm more used to the tools and think I can do a better job.

In just three hours today, I got as far as these pictures show. Notice the band along the edge is a totally consistent width. The carving isn't nearly as deep (though I really can't decide if I like the carving deep or shallow). Most of the speed came from roughing out the shapes with a high-speed cutting bit on my Dremel tool. If I can get to the point where I finish a leg every five days, I'll be quite happy.

I still can't quite get the organic look to the carving that the original had :(. It's getting better though.

Please take a look at the first leg a few posts down. I'd like to know other people's opinions!

Straight from the Mold

Here's the rose out of the mold. I now need to cut off the excess, thin the back (it's about 1 cm thick and only needs to be 5 mm) and file some edges so they're smoother.

(sorry... I'm too lazy at the moment to get my real camera out)

Edit 27-July: I decided I'm going to remake the rose, since it was fast. This time I'll tint the wax so I can actually see what I'm carving.

Casting the Rose

In the soundboard there is a 3" hole with a metal "rose" (medallion-like thing) in it. To make this, I poured a disk of wax, carved a positive rose, cast plaster around it, baked the mold, melted the wax out of the plaster, then melted a mix of lead and tin and poured it into the mold. (Actually... I'm not 100% positive what the metal is. I used plumber's bar solder, and it had the "this product contains chemicals known to the state of California to cause cancer..." warning on it, so it really could be any mix of lead, tin, silver, antimony and copper. I was hoping to find 50-50 lead-tin.)

I haven't broken the mold off yet, as the metal is still hardening. But here are pics of the casting!

Carving

Here's 90 percent of one leg. This took probably 100 hours. I still need to lightly etch the back sides, fill in the grooves from the roughing out (I roughed out with a band saw and intended to rough out more finely with a spoke shave, but never did, so the groves remained), finish smoothing out tool marks, and finally gild with 24 karat gold.

As always, click for larger images!

Tools used: V tool, four gouges of various sizes, angled flat blade, Dremel polishing wheels.

(I swear the leg looks better in person... these pics aren't great!)

Update for March

Parallel grain section of bottom complete (under the keyboard, the grain is perpendicular). All sides of cabinet complete. All belly rails and lower frame work complete. Wrest plank supports complete. (Done with dovetailing!)

Next comes the wrestplank, keyboard and upper frame work. I'm redesigning the upper framework so that it isn't prone to failure like the original instrument.

This morning I went to the Museum of Fine Arts before they opened to the public to photograph the painting with flash photography.
Many thanks to Aaron Kakos and the museum!

Photos!

I just got my cable to connect my cell phone to my computer. Below are the pics of what I've done so far. Click on any image to see the full-sized version.

Photos VIII

The result so far! Something to be said for full-scale plans. Completed in this photo are the two dovetail joints in the back, and the three pairs of sliding dovetails for the lower frame members. (clamp on bentside is to temporarily straighten out some cupping caused by the steam)

Photos VII

Milling the sliding dovetails in the bentside and spine.

Photos VI

Dovetails in the tail and bentside.

Photos V

oops- nicely done reversed dove tails. I cut these off and redid them.

Photos IV

More shop: two drill presses, 12" bandsaw, not shown: radial arm saw and miter saw to the right. I fit the entire bending form into the bandsaw to cut out notches to clamp in!

Photos III

The shop: 12" joiner, 6" belt sander, 24" planer...

Photos II

2. Bending form. Pain to make every the same -- I cut roughly to size with a bandsaw, then used a router and sanders. With Hayami's help, I got the bend into the wood within 60 second or so. First time bending the wood split.

Photos I

1. Steam bending 1x12 poplar. The hose goes to a wallpaper steamer. I just used a few layers of plastic bags as the steam chamber.

Dovetailing

I've spent the last week or so making the three corner joints and cutting the sliding dovetails for the braces.

Each of the three corner joints has five pins, and each is at some funky angle, such as 131 degrees, 59 degrees, and in the worst case, about 90 degrees but in the curve of the bentside. I've finished the two that are straight (that join to the tail), and am saving the curve for last. I've been doing the cutting with a Japanese back saw and Marples chisles. Each set of pins and tails takes about five hours.

The sliding dovetails were much easier and more fun. I did them all on a milling machine with digital X, Y tracking. I cut the matching tails in fir beams that span the width of the case on a router table. The beams were somewhat of a pain to cut, as they too are at such angles as 53 and 56 degrees.

Once I finish cutting all of the beams (they get tails in both ends, and a curve cut out of the middle), I'll do the final fitting of the tail corner dovetails, and glue it all together. Then comes the stringing (thin poplar that the soundboard rests on), the smaller crosspieces, the wrestplank and the bottom, and then I'm near done with the skeleton.

The Bentside

The case is made of poplar. I'm using FAS, FSC S4S 1x12 from Sterritt. First step was bending the bentside.

I made the form out of eight layers of plywood. The thing weighs about 40 kg and takes 10 clamps. My steaming apparatus is pretty sketchy... I just used plastic trash bags and a wallpaper steamer.

The first time I tried bending... well, it cracked. I had put a test piece in the steam bag, like I read is good to do. I tried bending that test piece, and it was fine. But when I took it out of the bag, I musn't have sealed it well enough, because the actual piece cracked significantly.

I suppose it was a bit of a good thing I got a new piece of wood for the bentside, as my first one I had to plane and join down to about 1.3 cm (0.5 in) from a desired 1.9 cm (0.75 in) due to cupping. The new piece is much straighter, though not very clear. Luckily, it worked.

I'm leaving the piece to dry in the form for about two months. However, just from leaving the cracked piece in the form overnight, I found that there isn't much springback at all!

I finished my first set of 90 degree practice dove tails (hand cut). They fit snugly, but don't seat as perfectly as I'd like (didn't clean out the waste cleanly enough). The actual ones that I need to cut (three joints) form joints at about 80, 120 and 110 degrees.

Off to Thailand and Malaysia...

Introduction

I'm a first year at MIT and I'm building a harpsichord.

I've played piano for about 12 years; since coming to MIT I've switched to (or added to my instrument breadth) harpsichord. It's a fantastic instrument that came before the piano. Instead of the strings being struck with a hammer, they are plucked with quills.

J. S. Bach didn't write much for piano - when it was invented, he wasn't thrilled with it, and continued writing primarily for harpsichord and organ as keyboard instruments.

This harpsichord is a very special one. It was built probably in 1736. The original is on display at the Boston Museum of Fine Arts. It is heavily gold leaved, painted very ornately, and belonged to one of the wealthiest families in France at the time.

An MIT alum, R.K. Lee, apprenticed under Frank Hubbard, who restored the instrument in the 70s. Lee drew up very inclusive plans of the instrument, which I am basing my construction on.

I'm doing most of the construction at the MIT Hobby Shop with the help of Hayami and Ken.