Saturday, February 2, 2019

One-Handed Saxophone

At the end of January, I had the rare and coveted (for me, at least) opportunity to travel to Wisconsin and spend a few days in the shop of Brian Russell doing some extensive modifications to a saxophone. I've known Brian for the past few years and even before then I knew his work, which is widely known among other technicians for being innovative, elegant, and incomprehensibly precise. I'd describe him as a "technician's technician" if he wasn't so accessible and so good at explaining things in layman's terms. He also has the sort of calm, thoughtful demeanor I aspire to, so when the opportunity came up to work with him, I almost literally jumped at it.
The instrument we modified is for a player who has limited use of his right hand, so that it can't be functionally used to play. He needed a left-hand-only instrument, of which Brian has designed and built several. That was advantageous, because it meant he already had a pretty good idea of what modifications we needed to make, we just had to work out some details and carry out the actual construction. The design balances functionality with practicality and economics. To build an instrument that would allow the left hand to play the entire range of the instrument would be incredibly complex and prohibitively expensive, plus it would require the player to learn an entirely new fingering system. (However it can, and has, been done, by Brian himself: http://www.russellwinds.com/onehandsax.html). So the design we used allows the player to play from Low E all the way up to the top of the normal range-High F, fully chromatic. He won't have the low range of the instrument, from Low Eb down to Low Bb, but the fact that he'll have just over two full octaves will allow a great deal of expression and versatility. By swapping out some of the original keys for OEM replacements and some new keys made from scratch, we got the added benefit of the work being completely reversible by any skilled technician. All they'd need to do is take off the new keys and reinstall the originals, then do a normal set up.
Put as simply as possible, the new design repurposes the left hand pinky touchpieces to operate F#, F, and E, which would normally be operated by the first and second finger of the right hand. C# becomes F# (by closing the E key, which is already designed to close the F#), B becomes F, and Bb become E by closing both F and E through tabs connecting those touchpieces. We also manufactured a mechanism to operate the High E key with the crook of the left hand, just like the other palm keys. We were able to purchase new E and F keys, and the G# pinky lever, but all of the other left hand pinky touchpieces and levers had to be made from scratch. Brian has developed and appropriated a lot of techniques to make the job go smoothly, like using temporary adjustable contact points between the new levers and the keys, to find the right balance between feel and travel, or “throw.” He also builds key arms so that they can be moved around before being brazed in place, to again allow adjusments to be made on the instrument. By making prodigious use of machine tools, he’s also able to cut down on manufacturing time, though most of the fitting, filing, sanding, and tweaking still must be done by hand.
We spent two very full days and another 8-hour “half” day working on the project. At that point we had built all of the parts we needed, and had opportunity to dress, buff, and lacquer all of the pinky keys. I headed back to Pennsylvania with the instrument and most of the keys, while Brian hung on to the High E mechanism, which still needed clean up, buffing, and lacquering. He’ll also build a handle for the player to stabilize the instrument in his right hand (which still has sufficient control to be able to grip). Finally, he’ll make some “dummy” key cups to hang over the Low B and Bb tone holes, since we took those keys away and used their positions to hold the new touchpieces. Once that’s complete he’ll ship all those parts to me for final assembly and set-up.
Even with the benefit of a well-outfitted machine shop, building keys by hand is a time-intensive and laborious process, especially to make them look as neat, clean, and precise as factory-made keys. The most complex part of the job, though, is to perfect the angles of those keys, contact points, and touchpieces so that parts mounted on different axes travel the same distances, and that pads move together and seal against their tone holes at the same instant. These are factors we take for granted in mass-manufactured instruments, because the design work and engineering has already been done. But to do that engineering, even with the firm foundation Brian can provide with his prior experience, made this the most complex and mentally challenging repair I’ve ever done.
The days were busy and illuminating. I learned a lot, and relearned some skills that I thought I knew. I barely had time to take out my phone, but I took as many pictures as I could in the time available. These represent a few small tasks in the larger project. As of the writing of this post, we're not done, so I'll try to post more pictures of the finished instrument after Brian sends the rest of the completed parts and I get everything installed.


Using the mill to drill holes for the roller screws in the new touchpieces. A rough outline of one of the touchpieces, which will eventually be cut out of this piece of raw brass, is visible in red. We made the tracing using one of the old touchpieces.


One of the new touchpieces mounted on its arm, which is mount to the hinge. Everything in this photo is new and hand made.


Using the mill to cut out the rough shape of another arm. A tracing of the final shape is visible in red marker.

The arm fully cut out, with the paper template that was shaped on the instrument, then traced onto the brass sheet. Using paper templates, which can easily be cut or discarded and replaced, helped us ensure we had the right geometry to navigate around any obstacles and create the most efficient connections, before making a single cut on the brass sheet. Heavy gauge brass is costly and time consuming to cut/shape, so minimizing wasted material and time is critical. We only had to scrap and remake one part over the course of the whole job.


Two of the new touchpieces.The right-hand touch is mounted on the arm shown in the two previous photos. 

The short pin protruding from underneath the arm (actually the top of the arm, it's just upside-down), is a temporary contact point used to find the final location for a permanent pin, which will engage the E key and close it when the lever is pressed. The temporary pin is soft-soldered to the arm, so it can be heated and moved. Moving it further out on the arm, or up and down, changes the way it interacts with the key by altering the distance the lever travels and the amount of force it requires. Once the ideal position was found, we set the lever in the mill, as seen here. Then a hole was drilled through the arm, right through the center of the pin, and a permanent pin was fit to that hole and brazed in place, ensuring it would be in exactly the same position as the temporary pin was.


The arm is visible at the bottom of this picture, with the aformentioned hole drilled through.

Using a bandsaw with a specialized blade to cut out the shape of the new E touchpiece, which matches the shape of the old Bb touchpiece. This blade cut through 1/8" brass like it was actual butter.

Brian taking an appropriate level of enjoyment from removing a roughed-out key part from a large block of brass. The part needed to be milled, but was too small to secure in the milling vise, so he soldered it to this large block, then fixed that in the vise. It worked perfectly!

The pinkish post ball near the center of the picture is the only non-reversible modification we did, as we had to braze that new ball onto an existing post to make one of the new levers shorter than the original. If someone wanted to reinstall the original keys, that ball would be in the way. They could cut it off if needed, I guess, but whereas everything else can easily be swapped between old (full functionality) and new (left-hand-only), this one piece would require major work to change. The pink color is a byproduct of the high heat used in brazing.

The new touchpieces and levers, mounted on the instrument and roughly set to height.

All the new parts for the F#/F/E mechanism after assembly, pickling (removing scale that builds up during brazing), dressing, buffing, and degreasing (then a little more buffing and degreasing). They're ready for a coat of epoxy lacquer.


Brian and I with the partially completed sax. The new keys pictured above are mounted, but the High E mechanism is not, nor are the "dummy" key cups for the bell tone holes. He'll finish those up, along with the handle, and send them along for me to do final installation and set up. Of course, you can't see much of the new mechanism in this picture, because we took it pretty hastily and didn't bother to stage anything, as we were about to jump in the car and head to the airport so I could catch my flight home. Like I said, they were full days!

Saturday, September 1, 2018

Antique Cornet Lever Bridge Repair

This antique cornet came across my bench in need of some...remediation. The levers and their clockspring mechanisms are mounted on a bridge, which is attached to the instruments by two feet. One of the feet had broken off and been replaced in a manner that could charitably be described as "haphazard." It was an inexplicably scalloped piece of brass, attached with generous amounts of solder and reinforced with some wire that may have once served a real purpose somewhere as a paperclip. I cut and shaped a new foot from brass, and then affixed it to the bridge with a small handmade brass rivet. A remnant of the original foot provided evidence that this was how it had been attached by the maker. A drawback of using a rivet rather than a screw is that it's more labor-intensive to install and can't be removed without destroying it, but the advantage is that it's very long-lasting and can't be jostled loose over time.

Here's the foot it had when it arrived on my bench, after I'd removed the huge glob of solder that had held it on the instrument, along with a few wraps of wire. The impression from that wire can be seen at the bottom of the photo in some excess solder that had flowed along its length.

Another view of the previous repair. Surprisingly (or maybe unsurprisingly because of how much solder and wire was involved) the joint had held and seemed pretty strong.


Here's the new foot from the underside, showing the rivet that holds it on to the bridge.
 
The new foot from above, contoured to match (well, sort-of match) the style of the other braces on the instrument. The circle visible on the end of the bridge is the top of the rivet.

Side view of the new foot.

All set to go back in to service!

Saturday, August 18, 2018

Laubin English Horn Hinge Tube Insert

This is the C key from the upper joint of a Laubin english horn, in for an overhaul. Since tight key fit is essential to stable padding when working with cork pads, I spend a lot of time in my overhauls fitting keys to remove any "slop" in the mechanism. A lot of times that involves sweding the tube on the key to shrink it a little bit, and make it fit more snugly on the hinge screw. However, this is one of several keys on an oboe that can't be swedged, because of the long arm that's attached along its length. There's not a good way to get a tool in there to shrink the tube if you don't have access to the entire circumference of the tube. If you look at the end of the tube on this key, you can see that it's been "wallered out" somehow, so the diameter is way too large on that end. That allows the key to wobble on the hinge. The normal way of dealing with this would be to make an oversized (greater diameter) hinge screw and ream the inside of the tube to fit it, thereby enlarging the tube enough to cut out the "wallered" section. However, I'd already made an oversized hinge screw for the entire left hand section on this instrument. There were other keys in that stack had also been loose, and they all fit beautifully after reaming and lapping to the new screw. However, this one was still loose. Not wanting to make an even larger screw and ream all the other keys again, I decided to make an insert for this tube that would allow it to fit snugly. 

The rough surface on the inside of the tube is where it was still loose on the oversized screw. The reamer that I ran through didn't even touch that area because it's so blown-out.

This thick-walled brass tube has a very small center hole, much smaller than the diameter of the hinge screw. After the insert is installed, that hole will help guide the reamers through as I gradually enlarge it to the correct size. It's being turned down to a diameter that will fit in the tube on the key.

Here's that same piece after being cut off and cleaned up in the bench motor.

The piece was "tinned" to make it easier to solder in place. The whole part was heated and solder flowed over the surface, then the solder was wiped off while still liquid, leaving a thin layer on the surface. When soldered in to the key, solder will flow much more easily over this surface than it would the raw brass underneath.

After soldering the insert. The end of it sticks out beyond the end of the key tube, and will be trimmed off later. The finished insert was intentionally made larger (greater diameter) than the hole in the key, and the key was reamed up to match it. That created a nice clean surface inside the key for soldering, and the inner diamter of the key tube was made uniform to match the outer diameter of the insert.

Reaming the insert up to size. Progressively larger reamers are used, each one removing a few thousandths of an inch of material.

The last reamer sticking out, having passed all the way through the insert. The chips of material it removed are visible on the end.

The interior surface of the insert is much smoother and more uniform than the original key tube.

After a little bit of lapping to remove to make the fit smooth, the hinge screw fits nice and snug in the key now, with no wobbling on either end.

Thursday, March 22, 2018

Loree Oboe Overhaul Time-Lapse Video

I've been wanting to do a time-lapse of a major repair for some time, so when this oboe came across my bench it seemed like the perfect opportunity. This is an AZ series Loree oboe from the late 1950's that hadn't been serviced in some time, so it needed a lot of attention. 6 minutes is probably a bit too long for a time-lapse, but the job took 20+ hours so I cut out as much as I could. That means a lot of little steps have been left out and some of the tasks that are shown will appear simplified. This video doesn't begin to show the amount of fussing and fiddling that goes in to every part of a comprehensive repair, but does give an idea. Most of the steps are directed toward ensuring that the pads are dead level to the tone holes and that they will close exactly the same way, in exactly the same position, with exactly the same relationship to other keys, every time for hundreds of thousands of repetitions.
That baking soda bath to remove tarnish was somewhat effective, but this was my first time trying it and I'll need to tinker with the process to see if can be improved. There was still a lot of polishing to be done after that.
The musical accompaniments are Perpetuum Mobile and Trish-Trasch Polka, both by Johann Strauss II.






Sunday, March 11, 2018

Oboe Octave Touchpiece Extension

This Loree oboe belongs to a local university, and is in use by a student who has difficulty reaching the thumb touchpiece for the octave key. Her professor asked if an extension could be made to improve the ergonomics, based on one she'd had made by another technician for another oboe. Making an extension plate is simple enough - it's just a piece of nickel sheet with the edges rounded over to remove any sharp burrs, and curved a little bit to match the contour of the body and fit in the case. In most cases, it's then soldered or brazed on to the original touchpiece. However, with this being a school-owned instrument, the extension will need to be removed at some point so that another student can use it. Removing a soldered or brazed part would require bringing it back to the shop and would leave residue that would require some amount of cleanup. So it made more sense to manufacture an extension that could be affixed mechanically, in this case by screws.

The extension needed to add at least 3/16" to the left side of the touchpiece, and I chose to make it a little longer than that just to be safe.
The process of making the extension isn't very interesting. A template was marked out on a sheet of nickel, cut out, and the edges sanded to achieve the right shape and contour. Then it was formed into a curved shape to somewhat match the curve of the instrument body. Holes were drilled in the plate where it would meet the underside of the touchpiece, then matching holes were drilled and tapped in the touchpiece. A couple of 2.0x0.4 metric screws were modified to fit, and the part was ready to install, which was as simple as screwing it on. That's it! The next few pictures just show the completed part.


The extension in place. It's thinner in the area that sits under the touchpiece, to allow for adequate travel of the key.

A view from under the key. The extension can be removed by anyone simply by unscrewing it.

With a cork on the extension, the screws are hidden. The cork contacts the body when the touchpiece is depressed to control key travel. When the extension is removed, a piece of cork affixed directly to the bottom of the touchpiece will serve the same function and cover up the screw holes, so there will be no visible evidence that the extension was ever installed.

The touchpiece with extension mounted on the instrument. 

Wednesday, January 24, 2018

Resetting a Buffet Clarinet Post

This Buffet clarinet came to me twice in the same year because the hinge screw on the Side F# key had snapped off at the threads. The first time I simply manufactured and installed a new screw, but I did notice at the time that it felt a little tight going in. This time I investigated further and discovered that the underlying problem was a misalignment between the holes in the threaded post and the unthreaded post, which hold the screw. The hole in the unthreaded post was angled too far downward, so that when the screw was fully inserted, that post pushed down on it while the threaded post pulled up on it. The screw broke at the end of the threads because that's where the diameter is thinnest and weakest. The fix would be to change the angle of that hole.

The way I saw it, there were three potential ways to address the issue:
1) Raise the unthreaded post so that the angle of the hole was in line with the threaded post. 
2) Drill out the hole in the unthreaded post, then solder in a bushing at the correct angle, using the screw as a guide. 
3) Completely fill in the unthreaded post with a soldered plug, then re-drill it at the correct angle using a post-drilling jig.
At the time, I didn't have a post-drilling jig (I do now!) so option 3 was out, but I did have a drilling jig for the body, as detailed in a previous post, so I chose option 1 to give that tool a workout, though option 2 would have been just as good.

The first step was to remove the post and drill out the post-hole in the body to remove the threads. Because the post's height and radial alignment are both dictated by how far it's threaded in to the post-hole, and because both of those variables have to line up at exactly the same point, new threads would have to be cut into a bushing, then aligned on the body.

The small hole at the center of the picture was the post-hole. This is after it was drilled out.
Below is the bushing installed on the post. It's just a piece of ABS plastic, turned on the lathe and threaded.


The post was threaded into the bushing before installation.
The bushing and unthreaded post were glued in to the post-hole in the body together, using the screw to properly align things with the threaded post. Once the glue set, the pad had to be replaced to account for the slightly different angle at which the key now meets its tone hole, and the problem of the broken screws should now be permanently resolved.


The repositioned post is at the center of the photo. Looking at the base, you can see that it's now raised slightly off of the body. It's not cosmetically perfect, but probably not the kind of thing you'd notice unless you were looking for it.

Wednesday, December 27, 2017

Holton Alto Horn Leadpipe

This Holton alto horn, circa 1913, came in to the shop with a leadpipe that was not only damaged, but mostly sheared off. That necessitated replacing the leadpipe and mouthpiece receiver, but the age and obscurity of this instrument meant that no replacement parts are available. The only option, then, was to custom bend a new leadpipe. 

The remnant that was still on the instrument appeared to have been a replacement, so I was already two degrees removed from being able to replicate the original. Because mouthpiece shanks weren't yet standardized in the first few decades of the 20th century, it's almost impossible to know what sort of mouthpiece and receiver this instrument was designed for, without seeing an original. Further, without those pieces of information, it's even more difficult to determine what the original leadpipe dimensions would have been.

However, we work in the real world, and one has to learn to work with situations where incomplete information is all that's available. What we did know were the dimensions of a modern alto horn mouthpiece (not quite the same as a trumpet, or a mellophone), and of a modern mouthpiece receiver. Having secured one of those, it was possible to figure out what dimensions would be needed for the leadpipe. In an ideal setting, we could have gotten a piece of tubing drawn to a custom taper to fit those dimensions, but within the owner's non-infinite budget the best option was to use a section of a universal cornet leadpipe that matched pretty closely. They wanted an instrument that would work reasonably well, and not a museum piece, so I had no qualms about making that compromise in the interest of efficiency. 

There are no pictures of the process, but below you can see the before and after. The new pipe came straight and was filled with pitch, so fitting it required bending by hand over wooden forms to acheive the necessary curves. The pitch prevents the tube from kinking, though it doesn't prevent any distortion around the bends, so after draining the pitch and cleaning the tube, it had to be rounded out by pushing through graduated dent balls. For that part of the process I always solder several braces across the tube to preserve the angle of the bends while working. After rough-buffing, the part was soldered on, then it got a color buff and a coat of lacquer. Why lacquer a brass part on a heavily tarnished silver instrument? I don't have a good answer for that, except that I thought it looked better than leaving the part raw and I took some pride in the final product. 

The instrument as it arrived, with the remnant of the old mouthpipe still in place. 

The new part installed, buffed, and lacquered.

Another view of the final result.