Lesson Learned - 5/30/12

Today I attempted to realign the 3rd valve slide on a Laskey-Pinc gold-plated trumpet. In addition to the slide being out of alignment the 3rd slide stop screw, which is threaded through the brace on that slide, was really tight and wasn't threading in at a right angle to the slide. It was slightly askew.


I found that the problem with the alignment was on the outer slide. The span between upper and lower tubes was not parallel, being about .005" wider at the ends of the tubes than at the brace that holds the slide in alignment. As I expected, the upper tube (which is an outer slide - the lower tube is an inner slide) was bent upward right at the brace. I expended a great deal of energy carefully trying different approaches to bend that slide back into alignment and make it parallel with the bottom tube, but after about an hour of trying it hadn't budged at all, even with a jig a put together that used a trombone handslide mandrel and a table leg for leverage. At that point I had to take a step back and consider this: If all the pressure I had exerted on the slide hadn't moved it one iota, then I was clearly going about things in the wrong way. Something had to have forced it out of alignment, but if the slides were that tough then it couldn't have been some conventional damage like a bump or a twisting of the slide. Something more complex and far stronger was at play.


It was at that point I began to reconsider the slide stop screw. The threads through the brace were really messy and looked chewed up. This in comparison to everything else on the instrument, which appeared to have been carefully machined, aligned, and assembled. It is a handmade trumpet, after all. It then occured to me that the stop screw threading through the brace at a skewed angle couldn't have been part of the original design, and it was likely that the screw had been cross-threaded by some mistake at some point. I called the customer to see if he could shed any light on the matter and, sure enough, he told me that he'd recently had the instrument apart for cleaning. While reassembling it he started to have trouble getting that screw to thread into the brace, so he repeatedly ran it forward and backed it out incrementally, in exactly the same way one would cut threads with a tap. That explanation made perfect sense, and it suddenly occurred to me why everything was going wrong.


When he was having trouble threading that screw, it was because he had started to crossthread it. Normally a crossthreaded screw will only turn a few rotations or less before completely binding up, but because the screw is made of steel, which is much harder than the brass in the brace, he was able to actually recut the threads in the post at an angle by being patient and running it in and out like a tap. Unfortunately the screw, having no reliefs in it like a tap, didn't just cut material out of the threads and clear it away. It displaced some metal, too, and in the tight confines of that brace stuck between two tubes, that metal went up and out, effectively making the brace taller by a practically microscopic amount. That was enough, though, to cause the brace to push the tubes farther apart, forcing the upper tube to bend slightly upward right where it is soldered to the brace. That was why my prior attempts to straighten the upper tube had failed - because the amount of force required to bend a piece of tubing in the exact spot where it's soldered to a rigid and substantial brace is massive. Somehow, though, that little steel screw had managed to put just that amount of force on the slide and cause the alignment issue.


With that little bit of detective work done, I was able to plan a new strategy. I called the manufacturer and actually got to talk with Ron Pinc, who makes all the slides, and checked the correct thread pitch for that screw (it's 4-40). Then I recut the threads in the brace (after running out to the store to buy a new 4-40 tap, as I discovered ours to be broken) and on the screw. With the screw working properly again, I moved on to bending the tubes back into alignment. Remembering that I saw an amusing infographic a few days ago about tourniquets and how they can be used to apply and maintain incredible amounts of pressure, I rigged up a tourniquet around the slide tubes right at the brace point, and literally pulled the upper tube back down toward the lower tube. Success! With just a couple of tries I was able to straighten the upper tube and realign the slide. A few more tweaks to align it to the slide tubes on the instrument are needed tomorrow, and things will be back in working order.


It may seem mundane, and even I didn't think such a small job would merit so much writing, but I was excited to do some real diagnostic detective work and discover how the damage had been done to that instrument in the first place. If you can figure what caused something not to work, you can almost invariably figure out a way to make it work again. Through patience and a methodical approach, I was able to just that, and it felt pretty great.


UPDATE: I also learned that you can't wipe excess solder from a solder joint on gold plate, because the solder will just go EVERYWHERE.

Lesson Learned - 5/29/12

When attempting to remove a stuck hinge screw from a saxophone, a good last resort measure is to unsolder one of the posts holding the screw in place (ideally an unthreaded post), then get a good firm grip on the newly exposed area of the screw with a set of parallel jaw pliers and slowly twist the screw out. This approach works particularly well if the head of the screw is chewed up from repeated attempts to back it out with a screwdriver.

Lesson Learned - 5/25/12

If you have only one set of dies for making screws (metric or english), then you have limited capabilities for making screws. But have if you both metric and english Screw Check'rs, you can sometimes use them to help you get around a lack of properly sized dies. The other day I needed to make a stop arm screw for a bass trombone rotor, but it was a European instrument with metric screws, and we only have American taps and dies. I needed a 3.0x0.5 metric screw (3.0 mm major screw diameter, 0.5 mm thread length), but we didn't have any on hand, so I was in a tight spot. My work-around was to cut a screw with 5-40 American threads (0.125 in. major screw diameter, 40 threads per inch), which is the closest American equivalent I had to a metric 3.0x0.5. In metric screw measurements, an American 5-40 would be about 3.175x0.635. Once I cut that screw, I carefully threaded it into the 3.0x0.5 slot on the metric Screw Check'r to recut the threads to that size. The reason I was able to do that is that the screw I was making was brass, which is much softer than the steel of the threads on the Screw Check'r. For a metal any harder than brass, I can't imagine the technique would work especially well. It's not a perfect solution - the threads weren't perfect - but the screw worked and I needed to get it done ASAP, so there was no time to find or buy a metric die. This way I didn't have to alter the threads in spindle to force an American screw to work, and the screw I made worked perfectly well.

Lesson Learned - 5/24/12

Today I learned that, no matter how hard you try to keep your birthday quiet from your co-workers so that they won't feel obligated to make a fuss over you, someone will find out and blow your cover. On the upside, though, your fiance may stop by after that with delicious cupcakes and macaroni & cheese. If you don't have a fiance, though, it's probably best to just keep your birthday on the DL.

Lesson Learned - 5/21/12

If a flute crown rubs up against the wall of the head joint as it's screwed in - in other words the crown screw isn't centered - it can push the crown cork off to one side and cause it to leak. This can be remedied by partially screwing the crown onto the crown screw, then tapping it with a rawhide mallet until the proper alignment is achieved.

Lesson Learned - 5/18/12

My coworker is regularly able to do what I am unable to - to recognize that a job has gone wrong before it's even finished, to stop, and to start over. I am irrationally afraid of doing the same. I will follow a task through to completion, through blinding frustration, even though I know it is doomed. My problem soldering a sax post last week was just such a task. Instead of stopping when I realized solder wouldn't flow because of the lacquer around the joint, I forged ahead, blasting the post with heat and flux until I'd burned off enough lacquer to allow the solder to flow. It created a huge mess and took extra time to clean up, which I fully knew and expected as I was doing it, but I kept going anyway.
Maybe I'm afraid that starting over will force me to admit that I don't always know what I'm doing. Maybe it's because I constantly try to avoid sunk costs, even though they are by their very definition irretrievable and utterly meaningless. M spent at least an hour shaping a brass rod to braze into a broken sax neck strap ring, realized the fit wasn't that great before he started brazing, and then started over again with a fresh length of rod to create a better fitting piece. He spent at least another hour on that, but ended up with a great result. Why I'm so afraid of doing the same I don't know - maybe because the prospect of one major failure is somehow better to me than two minor failures followed by a third successful attempt. The possibility that my second attempt might be no more successful than the first is upsetting, but it's one that I need to face. I know that I'll only get better through trying things until I get them right. I need to do a better job of overcoming my tendency to put on blinders and press on, and become more self-evaluative.
I need to remember that a self-criticism of my work is not the same as self-loathing.

Lesson Learned 5/17/12

Today I realized that my normal process of removing dents from an overhauled or repadded instrument after doing all other work on it is foolish. Dent work should come immediately after cleaning. Normally I do things like realign posts and raise dents that will affect the function of the instrument immediately after cleaning, then do all the other work (installing pads/stropping slides/porting pistons), and only then do I do cosmetic dentwork. But dentwork is easier to do when the instrument is disassembled, so it makes no sense to do it after putting things together.


I should come up with a tagline for these posts.

Lesson Learned - 5/16/12

Today I left a flute in silver dip for well over an hour because I forgot about it and was working on something else while I was cleaning it. Silver dip is fairly harmless so it didn't do any permanent damage to the instrument, it just came out super shiny. It reminded me of a habit I've fallen out of, though, which is to always use a timer when soaking an instrument in any sort of solution. Had the flute been in a more potent cleaning bath, some damage could have been done to the plating for certain. We have a timer in the shop, but I've fallen out of the habit of using it. Henceforth I resolve to serve the almighty timer once again!

Lesson Learned - 5/15/12

I crapped up a head joint tenon on a flute today while removing dents on a head joint mandrel and learned a simple lesson - always place a tenon shrinker on a head joint before doing dent removal. Even with the shrinker on, extra care needs to be exercised when removing dents from the top of the head joint, where a lot of leverage is needed.

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.

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.

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.

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.

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?