Tuesday, May 15, 2012
Lesson Learned - 5/14/12
While resoldering a post on a saxophone today, I encountered a problem I've had several times before, but one that I still fail to acknowledge at times. The flange on the bottom of the post was slightly larger than the footprint left by the old solder joint. In other words, when the post was originally soldered in place, the manufacturer didn't quite fill the joint with solder. Doing so leaves a nicer looking joint because there's no visible solder around the edges. Unfortunately, that also means that when the instrument is lacquered, that space on the body around the edge of the flange gets covered in lacquer. Since solder won't flow on or adhere to lacquer, that created a problem when I tried to resolder the post. Solder wouldn't flow into the joint even when I got it hot enough and applied an ample amount of flux, because the lacquer around the edges of the joint was creating a barrier. Eventually I burned off enough of the lacquer with heat, and the solder was able to flow, but it created a god-awful mess of burnt lacquer and solder in places where I didn't want it. I should have stopped when I realized the lacquer was causing a problem and dealt with that before attempting to solder, but I acted foolishly and hastily - two adverbs that seem to always travel together. I need to be more conscious of that problem in the future, and create a path for the solder by buffing away a small amount of lacquer at the feed point. As it was, my hasty method ended up costing me extra time because I had to go back to wipe away excess solder and buff all the burnt lacquer away.
Lesson Learned - 5/11/12
Further investigation is required, but I think today I learned that when shimming a flute pad, using a full shim that fits very snugly in the pad cup can cause the pad to distort once it's secured in place with the screw and washer. I've always been careful not to use full shims that are significantly smaller than the pad cup for fear that they would move around under the pad and change the way the pad protrudes from the pad cup. It never occurred to me that a snug shim could cause problems, too. I suspect that it's because the shim warps once the pad is against it and bubbles up in certain places, warping the pad.
Thursday, May 10, 2012
Lesson Learned - 5/10/12
Today I finished working on a Theo Markardt english horn, a peculiar instrument that required a lot of attention and study. From what I've been able to learn, Mr. Markardt made pro-level oboes and english horns in Erlbach Germany. I believe he's deceased now. The mechanism on the instrument was unlike any I've ever seen. The standard system on an oboe or english horn is known as the Conservatory System, and Mr. Markardt clearly used that system as his template but made numerous modifications. For instance, there were open tone holes and finger rings where the A and D pads would be on a conservatory instrument, some of the trill mechanisms were different, and the instrument had an automatic octave mechanism, which is fairly uncommon for double reed instruments. The fingerings were no different from a normal english horn except for a few trill fingerings, but the ways in which the keys interacted with each other were unique. Because of that I spent a lot of time just looking over the instrument, turning regulation screws, to get an understanding of how everything was supposed to work. Below I've included pictures of two of the mechanisms, along with my understanding of their functions and how to adjust them.
Automatic Octave Mechanism
Most double reed instruments have independent 1st and 2nd octave keys that the player operates manually. On this instrument, there was no way to manually open the 2nd octave key. It was connected to the 1st octave key and when the octave key was pressed, one or the other would open depending on which keys in the left hand were closed. This is exactly how the octave mechanism on a saxophone works. The design was unlike that commonly found on a saxophone, though. I've included the function of each adjustment screw and the order in which I found it best to set them.
F Resonance Key Mechanism
It seems like every brand of oboe or english horn has its own variation on this mechanism, so it usually requires a few minutes of study. This one had its own nuances, so its worth recording.
Because the adjustment of #1 can be affected slightly by #5, it could be necessary to go through this order more than once, making finer adjustments each time. Despite that, this is the best solution I could come up with.
This instrument taught me a lot, and since it's likely I won't see another one for a long time, these illustrations will help me be a lot more prepared with information that I wouldn't otherwise remember.
Automatic Octave Mechanism
Most double reed instruments have independent 1st and 2nd octave keys that the player operates manually. On this instrument, there was no way to manually open the 2nd octave key. It was connected to the 1st octave key and when the octave key was pressed, one or the other would open depending on which keys in the left hand were closed. This is exactly how the octave mechanism on a saxophone works. The design was unlike that commonly found on a saxophone, though. I've included the function of each adjustment screw and the order in which I found it best to set them.
F Resonance Key Mechanism
It seems like every brand of oboe or english horn has its own variation on this mechanism, so it usually requires a few minutes of study. This one had its own nuances, so its worth recording.
This instrument taught me a lot, and since it's likely I won't see another one for a long time, these illustrations will help me be a lot more prepared with information that I wouldn't otherwise remember.
Lesson Learned - 5/9/12
I spent most of today working on Gemeinhardt open hole flute. A fine intermediate instrument, but not the best, so it's to be expected that the tone holes would not be perfectly level. I find that having flat tone holes really makes padding an open hole flute much easier, so I usually level all the tone holes when I'm doing a repad, as was the case yesterday.
I was using a piece of plexiglass over the top of the tone hole and tapping with it on a hammer to lower the high spots, a tip I picked up from another tech on the Delphi band instrument repair forum. In doing so, I found that I need to be extra cautious if I'm tapping on the back of the tone hole, especially if there is a rib right next to it. If I tap too hard, creating a low spot in the back of the tone hole rim, it's extremely difficult to raise that back up to level because of the thickness and strength of the rib that prevents the metal from moving.
I was using a piece of plexiglass over the top of the tone hole and tapping with it on a hammer to lower the high spots, a tip I picked up from another tech on the Delphi band instrument repair forum. In doing so, I found that I need to be extra cautious if I'm tapping on the back of the tone hole, especially if there is a rib right next to it. If I tap too hard, creating a low spot in the back of the tone hole rim, it's extremely difficult to raise that back up to level because of the thickness and strength of the rib that prevents the metal from moving.
Tuesday, May 8, 2012
Lesson Learned - 5/8/12
Today I learned, courtesy of my coworker M, that reducing the venting of all the stack keys on a saxophone can help mitigate inconsistencies in the instrument's intonation. He was working on an old Martin alto and found that by closing the stack keys down lower than normal, he corrected a lot of the pitch issues in the middle register. The keys were so low that I would have never thought to experiment with an opening that small because it's so far outside the norm. But that saxophone reminded me yet again that I need to always be open to long-shot techniques when the tried-and-true aren't working.
I also learned that if you're going to plug a piece of tubing with silly putty to check for leaks, you shouldn't draw a strong vacuum on that piece of tubing because you'll suck a huge gob of silly putty up into the tube like a bubble in reverse. As a result of that little lesson, though, I learned that PB Blaster is really effective at un-sticking silly putty from brass tubing.
Seems like the first lesson was a bit more...nuanced.
I also learned that if you're going to plug a piece of tubing with silly putty to check for leaks, you shouldn't draw a strong vacuum on that piece of tubing because you'll suck a huge gob of silly putty up into the tube like a bubble in reverse. As a result of that little lesson, though, I learned that PB Blaster is really effective at un-sticking silly putty from brass tubing.
Seems like the first lesson was a bit more...nuanced.
Fighting "Blog Neglect"
This blog has lain dormant for awhile, partly because of a lack of motivation on my part. Based on just about every other blog on the internet, that seems like a common problem which I've named "Blog Neglect" (trademark pending). Part of my hiatus, though, has also been because I've put the project on temporary hold. At least I hope it's temporary
When I started working on the instrument, I had found it in the shop, talked to my coworker about it, and mistakenly believed that the owner had no more interest in keeping or paying to restore the instrument. I assumed it would an easy matter to contact her about purchasing it, so easy in fact that I wouldn't even need to talk to her before starting work. That's how certain I was that she'd want to get rid of the instrument. As it turns out I contacted her a few weeks ago and she wasn't as certain as I'd been about her willingness to sell. That's her prerogative of course, so while she's been mulling over whether to sell to me, I've agreed to stop my work. She knows about the work I've already done and is fine with it, and may even pay me to finish if she decides to keep the instrument for herself. We'll see - I've learned that it's best not to expect any specific outcome.
In any case I'd hate for this blog to go to waste, and for a while now I've wanted a way to keep track of the things I learn each day at work that I can apply to future repairs and to life in general. My plan from now on is to post every weekday with some lesson that I've picked up that day and ultimately end up with a wealth of information that I and others can refer back to. When my work on the english horn hopefully resumes, I'll continue to write about that along with the daily lessons, but in the meantime at least the people who stumble across this blog won't assume that it's abandoned and start smashing up the windows and doing meth in the bedrooms and squatting on the property. That's what happens to abandoned blogs, right?
When I started working on the instrument, I had found it in the shop, talked to my coworker about it, and mistakenly believed that the owner had no more interest in keeping or paying to restore the instrument. I assumed it would an easy matter to contact her about purchasing it, so easy in fact that I wouldn't even need to talk to her before starting work. That's how certain I was that she'd want to get rid of the instrument. As it turns out I contacted her a few weeks ago and she wasn't as certain as I'd been about her willingness to sell. That's her prerogative of course, so while she's been mulling over whether to sell to me, I've agreed to stop my work. She knows about the work I've already done and is fine with it, and may even pay me to finish if she decides to keep the instrument for herself. We'll see - I've learned that it's best not to expect any specific outcome.
In any case I'd hate for this blog to go to waste, and for a while now I've wanted a way to keep track of the things I learn each day at work that I can apply to future repairs and to life in general. My plan from now on is to post every weekday with some lesson that I've picked up that day and ultimately end up with a wealth of information that I and others can refer back to. When my work on the english horn hopefully resumes, I'll continue to write about that along with the daily lessons, but in the meantime at least the people who stumble across this blog won't assume that it's abandoned and start smashing up the windows and doing meth in the bedrooms and squatting on the property. That's what happens to abandoned blogs, right?
Sunday, December 4, 2011
The process...
for restoration seems straightforward at first, and one needs to have a clear plan when undertaking a project of this magnitude, but it would be foolish to expect that things will go according to the plan. The outline I've set for myself will therefore need to be flexible, and although I've laid it out in a step-by-step method, I expect that there won't always be clear separations between the steps. Some processes will need to happen simultaneously, some steps will "bleed" into each other, and there will definitely be times that I'll have to go back and fix issues that might not have arisen when I expected them to. It's only by having a flexible plan that one can go back and assess their work, adjusting and refining details to achieve the best possible results. A rigid plan would allow me the excuse of saying "once step C is done, it's done," forcing me to move on and preventing reflection on previous work. That's another reason this blog will likely help me. It will give me a structured way to analyze what I've done, which allows the opportunity to acknowledge the flaws in my processes and what can be done to refine them.
With that all being said, here's the outline of how I expect to proceed.
Step 1: Disassembly and Assessment
Disassembly might seem like an easy process. In some ways in can be one of the most fun steps. Destroying things is more fun than building them, with english horns as much as Legos, and the "organized destruction" of an instrument tear-down is one of my favorite parts of an overhaul. But it's a much more methodical process than, say, the crushing of a lego house with a pair of size 12's. First of all, disassembly is the time when parts are most likely to break or become damaged, especially if they haven't been moved in a long time. This is especially true of screws, which are almost always made of steel and therefore prone to rust. I've ruined the heads of many screws trying to extract them because I wasn't patient enough to work them out properly. On an instrument like this one, with long hinge rods and tiny shaft lock screws - which are as fine as watchmakers' screws - there are plenty of places for things to get stuck. After removal, screws need to be individually set in a screw board to insure they each go back in the right place. Complex mechanisms need to be diagrammed for reassembly, parts need to be measured, and notes need to be taken on what's missing. Fortunately, I've gotten most of the key disassembly done with no major issues. All of the screws came out with minimal coaxing, and only one pinned rod is really stuck. Next, though, I'll need to take notes on all of the pads and key corks before removing them prior to cleaning. The socket rings and liners will also need to come out for crack repair, and it may even be necessary to remove the octave key wells (which the octave pips thread into), but I really hope not.
Step 2: Cleaning
Cleaning involves three distinct processes: cleaning the wooden body, cleaning the metal keys, and cleaning the steel screws. The body will need to be cleaned by hand to remove dirt, organic material, and old oil. The keys can be cleaned in an ultrasonic machine (read more about that here) to remove surface deposits, corrosion and oil, followed by a silver dip to remove tarnish and hand-cleaning the insides of all hinge tubes and aperture holes. Screws can be polished with a fine abrasive to remove rust and buildup, and some will get a bath in WD-40 or penetrating oil.
Step 3: Body Repair
The most visible part of body repair is filling cracks and holes. This step will also involve inspection of tone hole edges to check for chips, and if necessary filling and leveling to create a smooth, consistent edge. Since the instrument will be padded with cork pads, it's imperative that the tone holes have no imperfections through with air can escape. Cork pads don't compress or deform to the shape of the tone hole rim, so even a small dip in the rim can cause a leak that will lead to problems.
If it's possible - rather, if I have access to the necessary tools - I may also use this step to replace the decorative section of the crown. The alternative to that would be filling in the chipped areas, but replacing it will create a much nicer final product.
The final step of body repair, once everything has been filled in and finished and the joints are checked for airtightness, will be to oil the body. In an instrument as dry as this one - and it will likely be dryer after more oil is removed during cleaning - the best option seems to be an immersion oiling, where each joint will soak in oil for a few days until it's soaked up as much as it needs. Oiling needs to take place last because oil in the wood can prevent glue from adhering, and gluing is a big part of crack and tone hole repair.
Step 4: Key Repair
As keys are moved up and down tens- or hundreds-of-thousands of times over the course of their lives, they inevitably wear. Any time two pieces of metal rub against each other, they will start to wear out, especially when one metal is softer than the other. In this case, the relatively soft silver in the keys is rubbing against much stronger steel in the screws. On keys held by hinge rods, the result is that the hinge tube (the part that the steel rod goes through) develops end play and lateral play.
Lateral play is dealt with by swedging, which involves carefully shrinking the diameter of the hinge tube until it's tight on the rod. As the tube is shrunk in this manner, the metal has to go somewhere, so it moves outward, making the tube longer in the process. As a result, swedging out lateral play can sometimes remove end play as well. When that isn't the case, it's sometimes necessary to attach extensions to the end of the hinge tube to take up any remaining end play.
On keys held in place by pivot screws instead of hinge rods, the process of removing play is much simpler. Since a key held on by a pivot mechanism is basically held in place by two points (the points of the screws on either end), it's just a matter of making the points of the screws snugly fit into the receivers on the ends of the key. This can be accomplished by making the screws go in further, either by modifying the screws themselves or countersinking the posts into which they thread. This takes care of both end play and lateral play.
Other parts of the key repair process involve straightening bent keys, and in this case manufacturing parts that have been damaged or removed. It'd be great to have a functional and attractive left hand F mechanism on this instrument, which means I'll have to build a new one from scratch. Other parts will have to be replaced or cleaned up to make everything functional again. That's an extensive and involved process that will get a thorough explanation later, when I actually do it.
Step 5: Padding
Once the body is prepared and the keys are fit and functional, it's finally time to do the part that most people think of as central to an overhaul - padding. This also involves installing all new key corks and tenon corks. Cork pads will be floated on a stiff, high-temperature glue that will hold them firmly level for as long as they last. The glue is not susceptible to environmental conditions such as cold or humidity, and so the precise orientation of the pads to the tone holes should ideally never change. If the tone hole edges are properly prepared and the keys are fit well, padding can actually be a somewhat quick and simple process. It's critical to have three levels when padding: a level tone hole, a level pad surface, and a level pad cup. Nowhere is this more true than when working with cork pads. Cork pads are the firmest and least forgiving pad material used on woodwind instruments. Ideally, one should also strive to have even pad protrusion - the height of each pad that's visible below its pad cup.
Step 6: Regulation
Regulation means controlling the various mechanisms that cause more than one pad to close at a time. This can be especially tricky on oboe and english horn, where some mechanisms close up to four pads at a time. For instance, the low C touchpiece closes the low C pad, the E and F pads when that key is open on high notes, the F resonance pad through the E pad, and when moving from Eb, it also closes the Eb pad. It's almost never called upon to actually close all of these at the same time, but they all have to be precisely regulated so that it could. Having level pads is key to effective regulation, and it's made much easier on an instrument like this that has regulation screws.
Once regulation is done, any slop in the mechanisms has to be dealt with. If one key starts to close, then catches one of it's dependent keys on the way down, that's known as lost motion, and is undesirable in most cases. Lost motion makes an instrument's mechanism feel unresponsive and "clicky." When one key closes another key (known as a dependent key), the ideal setup is that the dependent key start moving with the primary key as soon as it's pressed. This is achieved through properly trimming key corks and having consistent pad protrusion. A mechanism with no lost motion feels tight and gives the player positive feedback and a feeling of firmness when they close a key.
Step 7: Play Testing
Oh yeah! At some point, this project will produce something that's intended to make sound! Play testing is in some ways a rewarding process. Making sounds on an instrument that you've fixed gives a feeling of payoff and gratification, especially if that instrument has been unplayable for a long time, as this one has. It can also be a trying process, though, as it forces the technician to listen and feel carefully for problems with the instrument. Even an instrument that's been carefully worked on will have some sort of issues come up in the play test, and it's the mark of a professional to be able to hear those problems, find the faults in their own work, and figure out how to fix them. The technician must be their own worst critic in this stage.
Step 8: Lost motion
Once issues are dealt with and regulation is done, any slop in the mechanisms has to be dealt with. If one key starts to close, then catches one of its dependent keys on the way down, that's known as lost motion. In most cases lost motion is undesirable. It makes an instrument's mechanism feel unresponsive and "loose." When one key closes another key (known as a dependent key), the ideal setup is that the dependent key start moving with the primary key as soon as it's pressed. This is achieved through properly trimming key corks and having consistent pad protrusion. A mechanism with no lost motion feels tight and gives the player positive feedback and a feeling of firmness when they close a key.
Step 9: Voicing
Voicing is the step with which I have the least experience, and involves listening for tonal inconsistencies in the instrument and tuning issues with particular notes. If certain notes "pop" or sound muffled or certain notes are noticeably out of tune, they are dealt with in this step. Voicing can involve changing the height of key openings or placing material inside tone holes to adjust clarity or tuning. It's a meticulous process and requires great patience. One can expect a lot of frustration and minor setbacks at this point in the game, because the adjustments have become so fine.
Step 10: Profit!
Well, maybe not in this case, but if all the other steps are done well, the instrument should have a long playing life with minimal regular maintenance.
With that all being said, here's the outline of how I expect to proceed.
Step 1: Disassembly and Assessment
Disassembly might seem like an easy process. In some ways in can be one of the most fun steps. Destroying things is more fun than building them, with english horns as much as Legos, and the "organized destruction" of an instrument tear-down is one of my favorite parts of an overhaul. But it's a much more methodical process than, say, the crushing of a lego house with a pair of size 12's. First of all, disassembly is the time when parts are most likely to break or become damaged, especially if they haven't been moved in a long time. This is especially true of screws, which are almost always made of steel and therefore prone to rust. I've ruined the heads of many screws trying to extract them because I wasn't patient enough to work them out properly. On an instrument like this one, with long hinge rods and tiny shaft lock screws - which are as fine as watchmakers' screws - there are plenty of places for things to get stuck. After removal, screws need to be individually set in a screw board to insure they each go back in the right place. Complex mechanisms need to be diagrammed for reassembly, parts need to be measured, and notes need to be taken on what's missing. Fortunately, I've gotten most of the key disassembly done with no major issues. All of the screws came out with minimal coaxing, and only one pinned rod is really stuck. Next, though, I'll need to take notes on all of the pads and key corks before removing them prior to cleaning. The socket rings and liners will also need to come out for crack repair, and it may even be necessary to remove the octave key wells (which the octave pips thread into), but I really hope not.
Step 2: Cleaning
Cleaning involves three distinct processes: cleaning the wooden body, cleaning the metal keys, and cleaning the steel screws. The body will need to be cleaned by hand to remove dirt, organic material, and old oil. The keys can be cleaned in an ultrasonic machine (read more about that here) to remove surface deposits, corrosion and oil, followed by a silver dip to remove tarnish and hand-cleaning the insides of all hinge tubes and aperture holes. Screws can be polished with a fine abrasive to remove rust and buildup, and some will get a bath in WD-40 or penetrating oil.
Step 3: Body Repair
The most visible part of body repair is filling cracks and holes. This step will also involve inspection of tone hole edges to check for chips, and if necessary filling and leveling to create a smooth, consistent edge. Since the instrument will be padded with cork pads, it's imperative that the tone holes have no imperfections through with air can escape. Cork pads don't compress or deform to the shape of the tone hole rim, so even a small dip in the rim can cause a leak that will lead to problems.
If it's possible - rather, if I have access to the necessary tools - I may also use this step to replace the decorative section of the crown. The alternative to that would be filling in the chipped areas, but replacing it will create a much nicer final product.
The final step of body repair, once everything has been filled in and finished and the joints are checked for airtightness, will be to oil the body. In an instrument as dry as this one - and it will likely be dryer after more oil is removed during cleaning - the best option seems to be an immersion oiling, where each joint will soak in oil for a few days until it's soaked up as much as it needs. Oiling needs to take place last because oil in the wood can prevent glue from adhering, and gluing is a big part of crack and tone hole repair.
Step 4: Key Repair
As keys are moved up and down tens- or hundreds-of-thousands of times over the course of their lives, they inevitably wear. Any time two pieces of metal rub against each other, they will start to wear out, especially when one metal is softer than the other. In this case, the relatively soft silver in the keys is rubbing against much stronger steel in the screws. On keys held by hinge rods, the result is that the hinge tube (the part that the steel rod goes through) develops end play and lateral play.
- End play can be seen on just about any woodwind instrument, and is visible where a key can be moved back and forth between posts. Usually the movement will be minimal, less than a millimeter, but any amount of end play can make it impossible to do precision work on an instrument.
In this overhead diagram, the direction of end play is shown by the arrows. The gray gap between the edges of the key and the posts represents the hinge rod, which goes all the way through the key and will be visible in these gaps when end play is present
- Lateral play occurs when the diameter of the hinge tube gets enlarged by constantly rubbing against the steel rod. It's less easy to spot, but can be seen when a key can be wiggled on the rod. Lateral play is perpendicular to end play.
Even if a key is tight between the posts and has no end play, as would be the case in this diagram, there can still be lateral play.
On keys held in place by pivot screws instead of hinge rods, the process of removing play is much simpler. Since a key held on by a pivot mechanism is basically held in place by two points (the points of the screws on either end), it's just a matter of making the points of the screws snugly fit into the receivers on the ends of the key. This can be accomplished by making the screws go in further, either by modifying the screws themselves or countersinking the posts into which they thread. This takes care of both end play and lateral play.
Other parts of the key repair process involve straightening bent keys, and in this case manufacturing parts that have been damaged or removed. It'd be great to have a functional and attractive left hand F mechanism on this instrument, which means I'll have to build a new one from scratch. Other parts will have to be replaced or cleaned up to make everything functional again. That's an extensive and involved process that will get a thorough explanation later, when I actually do it.
Step 5: Padding
Once the body is prepared and the keys are fit and functional, it's finally time to do the part that most people think of as central to an overhaul - padding. This also involves installing all new key corks and tenon corks. Cork pads will be floated on a stiff, high-temperature glue that will hold them firmly level for as long as they last. The glue is not susceptible to environmental conditions such as cold or humidity, and so the precise orientation of the pads to the tone holes should ideally never change. If the tone hole edges are properly prepared and the keys are fit well, padding can actually be a somewhat quick and simple process. It's critical to have three levels when padding: a level tone hole, a level pad surface, and a level pad cup. Nowhere is this more true than when working with cork pads. Cork pads are the firmest and least forgiving pad material used on woodwind instruments. Ideally, one should also strive to have even pad protrusion - the height of each pad that's visible below its pad cup.
Step 6: Regulation
Regulation means controlling the various mechanisms that cause more than one pad to close at a time. This can be especially tricky on oboe and english horn, where some mechanisms close up to four pads at a time. For instance, the low C touchpiece closes the low C pad, the E and F pads when that key is open on high notes, the F resonance pad through the E pad, and when moving from Eb, it also closes the Eb pad. It's almost never called upon to actually close all of these at the same time, but they all have to be precisely regulated so that it could. Having level pads is key to effective regulation, and it's made much easier on an instrument like this that has regulation screws.
Once regulation is done, any slop in the mechanisms has to be dealt with. If one key starts to close, then catches one of it's dependent keys on the way down, that's known as lost motion, and is undesirable in most cases. Lost motion makes an instrument's mechanism feel unresponsive and "clicky." When one key closes another key (known as a dependent key), the ideal setup is that the dependent key start moving with the primary key as soon as it's pressed. This is achieved through properly trimming key corks and having consistent pad protrusion. A mechanism with no lost motion feels tight and gives the player positive feedback and a feeling of firmness when they close a key.
Step 7: Play Testing
Oh yeah! At some point, this project will produce something that's intended to make sound! Play testing is in some ways a rewarding process. Making sounds on an instrument that you've fixed gives a feeling of payoff and gratification, especially if that instrument has been unplayable for a long time, as this one has. It can also be a trying process, though, as it forces the technician to listen and feel carefully for problems with the instrument. Even an instrument that's been carefully worked on will have some sort of issues come up in the play test, and it's the mark of a professional to be able to hear those problems, find the faults in their own work, and figure out how to fix them. The technician must be their own worst critic in this stage.
Step 8: Lost motion
Once issues are dealt with and regulation is done, any slop in the mechanisms has to be dealt with. If one key starts to close, then catches one of its dependent keys on the way down, that's known as lost motion. In most cases lost motion is undesirable. It makes an instrument's mechanism feel unresponsive and "loose." When one key closes another key (known as a dependent key), the ideal setup is that the dependent key start moving with the primary key as soon as it's pressed. This is achieved through properly trimming key corks and having consistent pad protrusion. A mechanism with no lost motion feels tight and gives the player positive feedback and a feeling of firmness when they close a key.
Step 9: Voicing
Voicing is the step with which I have the least experience, and involves listening for tonal inconsistencies in the instrument and tuning issues with particular notes. If certain notes "pop" or sound muffled or certain notes are noticeably out of tune, they are dealt with in this step. Voicing can involve changing the height of key openings or placing material inside tone holes to adjust clarity or tuning. It's a meticulous process and requires great patience. One can expect a lot of frustration and minor setbacks at this point in the game, because the adjustments have become so fine.
Step 10: Profit!
Well, maybe not in this case, but if all the other steps are done well, the instrument should have a long playing life with minimal regular maintenance.
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