Sleeving the Upper Joint of a Clarinet

Every now and then, an instrument comes along that makes you say "What?" and/or "Huh?" and/or "Seriously, what?" This clarinet quickly went from a request for a tune-up, to an overhaul, to a major bore repair. The story is that many years ago, the top of the instrument was smashed, cracked, and started to split apart. Two enormous cracks testified to that, as did two flush bands and a tenon ring installed by a previous technician. Actually, a flush band would have to be flush by definition, so really it had one flush band and one, uh, hose clamp? It was a very nice hose clamp, though.

Whoever did that repair clearly cared about their work, and was proud enough to have engraved their name on the tenon ring. I'd like to think that if he were doing this job today, with access to modern adhesives, materials, and know-how, he would have taken a different approach and done a really nice, attractive repair. But 40-50 years of being constricted by those bands really took a toll on the instrument. With nowhere to go as it swelled and contracted, the wood split and splintered into the bore. The original cracks, held together only with shellac, reopened and extended. By the time we got to this instrument, it was in sad shape.

The previous repair, with hose clamp, flush band (really nicely installed) and a tenon ring/cap.

After removing the hose clamp and washing the wood to remove old oils and shellac.

Inside the bore, looking down from the top of the joint.

Another vew, showing just how severe the damage was and how far the splinters protruded into the bor.

With the bore in that condition, the instrument was uplayable, even if it hadn't been leaking through the cracks. We weren't sure how to proceed,so we tried several methods to smooth it out. After removing both bands to relieve the constriction/tension, we tried humidifying the wood, then letting it rest, then pushed it over a fitted steel mandrel and left it there for days (the Votaw .585" mandrel happened to fit perfectly, which was a bad sign because the bore of this upper joint should have been .576"), then let it rest for even more time, but nothing moved. 

It seemed like a loss, but the owner has a strong attachment to this instrument. I had arrived at the limit of my experience, so we reached out to Mark Jacoby, a legendary clarinet specialist in Philadelphia. He was kind enough to give us some of time to evaluate the instrument and strategize. He tried a few things that helped somewhat, but we all agreed it wasn't enough. He let us hang around in the shop a while, though, and in passing mentioned the possibility of installing a sleeve in the joint. That would mean boring out the damaged section of wood and machining a plastic insert to replace it. After we departed (reluctantly, as Mark is a really great guy and a font of knowledge), that idea stuck in my head. I was drawn to it for a simple reason: I was about to send off my own english horn to David Teitelbaum in New York to have a sleeve installed in the upper joint, and was inspired by his incredible work to stretch my own skills. I knew I couldn't do such a job on an oboe or english horn (yet), but a clarinet seemed feasible. How serendipitous it was that I happened to have this instrument in the shop. When my english horn came back playing like new, there was no doubt I was going to attempt this job. Cue the A-Team theme (with NBC Television's OK)...

ABS stock for the insert is set up in the lathe and center-drilled.

The insert was drilled out to .500"with a regular drill bit. The finished bore dimension will be .576" at the top, and tapered down from there

After drilling the inside but before boring, the outside dimensions are turned. The outside of the sleeve had to be .875" in diameter to match the cutter that would bore out the damaged wood from the upper joint.

Sleeving the upper joint requires the original tenon to be removed, and the replacement tenon is integral with the sleeve. Here the groove is being cut to hold the tenon cork.

The (mostly) finished tenon.

Boring out the insert to be closer to the final dimensions. I chose to do this before installing it, as my lathe isn't large enough securely hold the entire upper joint for boring.

Boring left a surprisingly smooth finish, but it will be reamed later to create the necessary (slight) taper.

Measuring the internal dimension of the insert. With that done, it was time to move to the instrument.

The original tenon was chucked up and cut off.

A .875" aircraft counterbore was used to bore out the upper joint. The cutter is centered by a pilot that passes through a fitted plastic guide inserted into the bore. The hose clamp (an actual hose clamp this time) is to prevent the joint from flexing and splitting along the existing cracks. Removing so much wood significantly thins out and weakens the wall of the joint, thus the need for reinforcement.

One of the cutter teeth visible through the Bb trill tone hole. About 2.5 inches had to be removed, to just above the Throat A tone hole.

Two views of the upper joint after boring is complete. The counterbore left a very nice finish. The two spots visible in the second picture are the holes for the register key posts.

With the insert in place. The insert was left long to allow room for error. Not that I make those.

Cutting off the excess.

The upper joint and insert just before assembly.

The insert was epoxied in place and set on the lathe to cure. The lathe here is simply serving as a work fixture - its rigidity prevents anything from moving as the epoxy sets.

With the epoxy set and cleaned up, the seam between the body and tenon is nearly invisible.

Looking down the now straight and even bore

All that remains now is to redrill the three tone holes covered up by the sleeve, ream the insert (with Mark's help, as I don't have the necessary reamers), band the cracks with carbon fiber to prevent them from extending any further, then oil the joint and proceed with a normal overhaul. In just a few weeks this instrument will be up and running like nothing ever happened.

Incidentally, if I actually had played the A-Team Theme song while I worked on this, it would have played 184.6 times before I was done. I really took my time to avoid any potential catastrophes. Meanwhile, the actual A-Team could have retrofitted 500 vans for non-lethal battle and still had ample time left over for Mr. T to pity several fools.

PMEA Presentation

For those teachers that attended my presentation at the PMEA inservice today, here are the links to the documents from the presentation, with full-color pictures and what-not:

Powerpoint Presentation (well, Google Slides, so no need to sign in or download anything): https://docs.google.com/presentation/d/1Jw3k4L7Hfkm3F5BH3BZTYdDhJN7Oada3a4wvgcMt6A0/edit?usp=sharing

Tool list: https://docs.google.com/document/d/1YUJUk9zB0f4NI08KvO0T7QLd3hNIv-ez6ekQ2ku6QVQ/edit?usp=sharing

Please contact me if you have any questions, and thanks for coming!

Saxhorn Dent Removal

A regular customer who plays in a Civil War band brought in this over-the-shoulder tenor saxhorn that had taken a bad hit on the upper bow. The resulting dent was so deep that it almost closed off the tube, rendering the instrument unplayable.

It would've been a neat instrument to work on even without the dent work. We dated it to sometime in the later 1800's, although it fits as a Civil War era instrument as over-the-shoulder horns were patented in 1838 and had become commonplace among brass bands in the 1860's. We call them saxhorns, as the musicians did at that time, although strictly speaking saxhorns were patented by Adolphe Sax in 1845 and of a very slightly different design. True saxhorns were more commonly upright instruments, though marching musicians preferred these over-the-shoulder instruments because they were easier to carry. This one uses Berlin valves, an early piston valve design from the 1830's that also fits with the period, though apparently over-the-shoulder instruments more often used rotary valves.

The other notable thing about this instrument that will forever burned into my memory is that the brass was t-h-i-c-k. Whatever caused that dent must have fallen out of an airplane or the space station to have left that kind of damage. Anyhow here's a little photo essay of the process.

The dent was in the upper bow, indicated by the white line, which had to be pulled off. As a bonus, the leadpipe coming out of the 1st valve casing also came off in the process. Great!

The tube had to be annealed to soften it, then the first part of the dent removal process was to raise the dent enough that a ball would be able to pass through it on the inside. That meant soldering a brass plug into the center of the dent, chucking the plug into a vise, and pulling on it until the solder failed and the plug let go. That process was repeated three times to get to this picture. Prior to that the dent was so deep that there was a danger of the brass folding over itself as the distortion was raised. This process mitigated that risk.

After working several graduated dent balls through the dent, the surface is smoothed out some but the area is still significantly distorted. The tube has to be repeatedly annealed to soften it, as the process of repeatedly hammering and reshaping the metal is constantly hardening the brass.

Getting closer! The last few balls needed to get the tube up to the right diameter went through very slowly. Patience is key.

After buffing and mounting, here is the finished part. Hey, I got the leadpipe reinstalled, too!

One more before and after.

Jarde Oboe - Left F Modification

This was a great project I got to do recently - adding a left F lever to an older oboe that didn't have one. It used to be you could order all or most of these parts from Fox and build the mechanism yourself, but they've recently made it more difficult to do that so I started from scratch. I got a chance to break in the new (old) lathe by trying some single-point threading and making hinge tubing from a solid rod, using a technique I read about from another tech. Plus I inhaled a lot of nickel dust cutting the keys out of a solid bar.

When making the posts, the rough shape was first turned on the lathe.

The threads on the posts were cut on the lathe to match the existing posts already on the instrument. The posts were going into new holes, so it would have been possible to tap them with any thread, but for consistency's sake I kept the same measurements as all the existing posts.

The final shape was filed by hand using a bench motor.

New post holes were drilled on a press, then the holes were tapped and the posts were checked for fit. The "caps" on these posts were left on to provide something to grab on to while they were repeatedly removed and reinstalled.

This swell post-drilling jig (made by Matt Slauson up in New York-thanks Matt!) keeps drill bits aligned to the center line of the posts while drilling holes for the screws.

Evidently I forgot that I had a camera for awhile, so there's a few scenes missing between this picture and the last one. But you can see the hinge tube mounted between the posts and through the key. A new screw goes through the posts and hinge tube. The lower part of the left F touchpiece is shaped and waiting to be brazed to the upper part

A view looking down toward the new post for the rocker part of the mechanism. Originally the post in the center of this picture was threaded to hold a screw, now it's been bored out so that a longer screw can pass through and thread into the far post.

A side view of the touchpiece, now with the upper part brazed to the lower part. The other keys have also been reinstalled.

The rocker mechanism engages with a new tab brazed onto the original F key. A long screw passes through the D trill touchpiece (on the right) and continues through the rocker and into the new post on the left.

The rocker passes under the long rod for the Eb/Low B/Low Bb keys

A general view of the new touchpiece and rocker, all finished and ready to ship!

A half-hour at Schilke

Schilke was the quickest of the tours I went on during my little repairman's intermission. Partly because it's a much smaller company - only 30 employees - partly because they seemed pretty busy and maybe wanted to get me the hell out of there in the politest way possible. Also, they didn't allow photography, so the unspeakable things I saw happening in there will remain locked in my own mind.

No, actually, they were very nice and it was neat to see the legendary craftsmanship that they're know for. Surprisingly, the manufacturing process was pretty similar to what I saw at Bach despite the difference in their much lower output. They do a few things in different order and people move around a little more between stations, but there's only so many ways to crack an egg.

Egg cracking is not one of the things I saw happening. I think they outsource that.

I got a picture outside, though!

Honesty is Important

I wish more politicians would have the courage to admit that they don't know how to play english horn: http://chicago.suntimes.com/politics/7/71/555085/bruce-rauner-isnt-award-winning-english-horn-player

A day at Bach

OK, it wasn't really a day, it was just an afternoon, after I visited Fox in the morning. They're only about an hour apart, you know.

The Bach plant in Elkhart was originally a Conn factory, but Bach has been here for several decades. Conn-Selmer, their parent company, has their HQ next door and a woodwind plant down the street. Since Blessing stopped manufacturing activities at their plant on the north end of town last year, there are only three plants left - Bach, C-S, and Gemeinhardt flutes.

Though it employs about the same number of people as Fox, the plant is significantly larger, owing to the massive machinery. Brass instruments come together much more quickly from raw material to finished product, but there's a lot more shaping and manipulation of those materials that has to happen along the way.

Press #1, which stamps out small parts for brass instruments and parts for woodwind keys. The factory maintains enough parts for 4 days of production, meaning that any given part goes from raw material to being mounted on an instrument in less than a week.

Unlike at Fox, where all the parts for keys were cut from blocks of nickel, at Bach they're stamped out on presses, then sent down the street to the woodwind plant. 

The draw benches, where tubing is placed on a precisely sized mandrel, then pulled through a lead die to reduce it to the needed diameter.

Across from the draw benches are enormous presses that take large sheets of brass and force them around a mold to make the rough shape of a bell. The excess is cut off and the ends are brought together and brazed , then hand-forming begins. Most makers don't press a shape into the brass like this. The maker would start with a cut piece of flat brass that gets hand-hammered around a forming mandrel and brazed together.

After the ends are brazed together, the seam is pressed together in this machine to make it perfectly smooth. This pressing mostly flattens the bell, so it will then get re-opened on a mandrel. After that it's repeatedly hammered on a forming mandrel and annealed until the desired shape is achieved.

Hand-hammering leaves the bell with a rough faceted surface, so next it gets spun and burnished onto another forming mandrel to smooth out any distortion. You can see the lever and fulcrum used to do hold the burnisher right under this guy's arm. It takes a serious amount of force.
After burnishing, the edge of the bell is partially rolled over, then a wire is soldered in around the whole circumference, and the edge is rolled the rest of the way to completely cover the wire. At this point the shape of the bell flare and stem are complete.

Next the bell is filled with soapy water, frozen to about -180 F, and bent by hand around a bending block to create the curve at the back of the bell. The ice prevents the tube from getting crushed when it's bent. The addition of soap makes the ice somewhat flexible. The freezer is at the left in this picture, and the bending block is on a stand in the middle of the shot.
The traditional medium for bending tubing is pine pitch, which a number of companies and small shops still use, but it's a pain to clean up, while ice can just be melted out.

While the bells are being made, other parts are coming together as well. Valve blocks and rotor casings - which is what's on the stand - are brazed together under very high heat.

Parts are cut-buffed before being assembled to clean the surfaces and prep them for soldering.

Apparently this machine can buff whole instruments. It wasn't running that day, but believe me, it smelled pretty great.

Finished bells wait to be mounted.

After the bodies are soldered together, they come to this room for color buffing and ragging to get a smooth, bright, finished surface.

This woman was soldering slides together. I distracted her and she knocked a brace out of position. Sorry.

Finally, the finished instrument comes here, the lacquer prep room, where it's wiped down and plugged up before going into the lacquer spray booth.

This machine doesn't make mouthpieces, it just buffs them, up to 1000 a day, before they're sent across the street to the plating shop.

After instruments are finished - either lacquered or silver plated, they come back to have the casings honed and the valves fit. This is the final manufacturing step before the instrument is checked and shipped out.

Here's a couple articles about the once-mighty band instrument industry in Elkhart.
One about the Blessing shutdown: http://www.elkharttruth.com/news/business/2014/03/14/Longtime-Elkhart-horn-maker-stopping-production.html
And an older NPR story from when things looked a little brighter:
http://www.npr.org/templates/story/story.php?storyId=124583703