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

A day at Fox

On my way out to the NAPBIRT conference today, I had the eminent privilege to spend a few hours at the Fox factory with Chip Owen, a legendary member of their staff and of the repair community at large. Chip is a man of few pretenses who seemed only too happy to take a couple hours out of his day to show me around their facility. Ever since I first picked up a Fox oboe 15 years ago in high school I've wanted to visit South Whitley, so I geeked out quite a bit.
Chip is a bassoonist and head of the contrabassoon department at Fox, so most of my time was spent around those instruments. He was kind enough, though, to humor me with a trip through the oboe/english horn rooms, too. The output of the facility is staggering - they have 120 people working on every step of the manufacturing process, from raw logs to finished instruments, and they produce thousands of instruments annually ranging from beginner to the most elite professional levels. As Chip pointed out, they are likely the world's largest manufacturer of bassoons, nestled in a small cluster of building on a rural Indiana road.

We jump right past aging, seasoning, rough shaping, and reaming. There are stacks and shelves of drilled logs sitting throughout the building waiting to be processed, and buildings outside where they age. This stage comes immediately after reaming, where the tenons are cut and the profile of these bass joints has just taken shape.

A few feet away, preformed plastic liners are fitted to wing joints. Pro line instruments get hard rubber liners.

A cut-away shows the installation of the liner.

In the same room, this machine bores bells for bassoons, oboes, and english horns. All other joints have their bores reamed, but bells are too large and irregular for that. There's a bell held snugly inside that steel sleeve.

After the joints are shaped and the liners are installed in the wing and boot joints, they wait here for final sanding and finishing.

In the sanding room, joints are smoothed and then matched together to make an instrument. Up until this point, no joints have been assigned to each other, but from here on out they will stay together as a complete bassoon.

In the tone holing room, a few recesses and holes are cut before finishing. Then the instruments gets finished and comes back here to have the rest of the tone holes and post holes cut.

Tone holes and post holes are cut by hand on a mill. Lying on the bed is a template joint used to set the angle of the drill for each hole. That hole will be drilled in 10 or 20 joints, then the machine gets reset for the next hole, and so on until every hole gets cut on every joint.

The tone holing machine for oboes wasn't running the day I was in, nor was the spellcheck.

Joints in various stages of completion sit throughout the building. Notice that they're all grouped to form complete instruments.

Posts are installed and drilled in this room.

Posts are installed as blanks, then a jig is used to center a long drill that cuts the holes for the screws perfectly parallel or perpendicular to the body.

As the posts are drilled, hinge rods are also fitted. They'll later be removed and have keys brazed to them.

The man himself, explaining post placement and drilling.

Key parts can be cast, forged, or cut. At Fox, the parts are all cut from huge slabs of nickel silver on a set of CNC mills. These are bassoon ring keys, part-way through the cutting process.

After the key parts are cut, they're assembled by hand. The keys for each bassoon are assembled to fit that specific bassoon, so the key finishers have to cut, shape, and file the parts before brazing them together, all the while checking the fit on the joint. Note the guide sitting on the Ab tone hole to center the key cup over the hole.

This room is where pads and corks are installed, then instruments are sent for play testing and adjustment before they're shipped out. Note the work orders sticking out of the bells, indicating whether an instrument has already been purchased and by whom.

I tried to snap a few pictures of the oboe and english horn manufacturing process, but like I said, Chip is a bassoon guru, so we spent a lot more time looking at the heavy artillery.

Oboe and english horn parts after reaming and external shaping. After this they would go to tone holing.

Posts and rods are fitted in the same room with bassoons.

Several oboes getting their keys fitted. After keys are assembled and roughly fitted, they're driven up to Elkhart, IN in large batches to be plated, then brought back the same day or next day for final fitting and padding.

I liked this stack of bell rings.

Oboes waiting for padding.

Oil isn't oil

A good-condition Bundy trumpet recently came across the bench with stuck valves and a request for a cleaning. That sounded simple enough, especially knowing that stuck valves usually just need to have their crud broken loose and they'll slip the rest of the way out. That wasn't the case here, though, as the valves refused to move at all. Removing the top and bottom caps revealed a thick green sludge throughout all three casings that was holding the valves tight. It was clear that someone had oiled this instrument with vegetable oil, perhaps under the mistaken belief that all oils are equal. I'd hate to be that guy's mechanic.

On facing this project, though, I thought it would be a good opportunity to share a couple pieces of research on why vegetable oil is unsuitable as a valve lubricant.

Mineral Oils and Organic Oils are fundamentally different.
If you use any regular (non-synthetic) valve oil, you'll see on the the side of the bottle that it contains petroleum distillates. A petroleum distillate is just a product made from refining crude oil, like kerosene, mineral spirits, motor oil, or in this case valve oil. Collectively these products are known as mineral oils, to differentiate them from organic oils like vegetable oil. To make things more confusing, mineral oil is also used to describe a specific type of petroleum distillate. It's the main ingredient in baby oil, is used as an animal laxative, and makes up the majority of commercial grade valve oils. 
Organic oils, on the other hand, are lipids produced by a diverse array of animals and plants. They share some basic chemical properties with mineral oils in that they contain a lot of hydrogen and carbon and repel water, but are derived in a completely different way from different sources.

Mineral Oils and Organic Oils have different physical properties
Mineral oils are thin at room temperature, with a relatively low surface tension between 22 and 28 dynes/cm. The average vegetable oil, on the other hand, has a surface tension of around 35 dynes/cm at room temperature. That added viscosity means that vegetable oils are too thick to fit in the small space between, say, a trumpet piston and its casing, which averages .025mm.

Organic Oils oxidize
Like the plants or animals from which they're derived, organic oils spoil after a time. It may take months or years, but vegetable oils will eventually go bad, and the high-humidity environment inside a brass instrument speeds up that process. Probably not a huge concern unless you plan to cook with it after you've used it to oil your trumpet, but worth mentioning.

Fortunately for me, Wayne Tanabe of Yamaha has a quick method for extracting the valves using a mouthpiece puller. I hope that posting these pictures won't infringe on his intellectual property, but the simple principle is that the valves don't need a huge amount of force to be pulled free, they just need a moderate amount of force, applied consistently. It does, however, require more force than your humble author could provide with my bare hands. A mouthpiece puller can provide it, though, thanks to that wildly popular simple machine, the screw.

The Bobcat made quick work of the valves. It really didn't take much pressure.

The oil got everwhere in the pistons, casings, and caps, and even oozed into the 1st and 2nd slides.

Having extracted all three valves, it was easy to see why they were so stuck. The buildup was thick and stubborn. Two cleanings in an ultrasonic only removed about half of the offending crud, and the rest had to be attacked with naphtha (a petroleum distillate!) and a large pile of cotton swabs.

If you want to know more about mineral oils, organic oils, or even synthetic oils, just visit your local library!

Just kidding, nobody goes to the library anymore. Go to Wikipedia. Or these other sites:

http://www.northerntails.com/images/What_are_Petroleum_Distillates.pdf

http://www.protectall.com/artpetdist.aspx

http://www.canitgobad.net/can-vegetable-oil-go-bad/