Hi, as most of you know I've been studying band instrument repair at Minnesota State Southeast Tech in Red Wing for the past 2 months. I've been having an amazing time learning from the best in the BIR world. I just finished brass fundamentals and I start woodwind fundamentals on Monday. Even though this was just the fundamentals course it got pretty intense, as you'll see below. It's only been 2 months and I'm amazed of how much I've learned, hope you are too.     

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Let me walk you through how I got from here to here..
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     I was one of two students in the class to get a silver plated pro horn as a project instrument. It was a great honor to work on such a good trumpet. However, it provided many hurdles including its plating, very specific specs, and what could possibly be the world's hardest bell. Silver plating was the number one hurdle to overcome. Silver plating can't be buffed like regular unplated instruments. This means you can't buff away the extra tinning around solder joints and make them look pretty. So you have to do an amazing solder job with limited feed spots to make it look good. Another issue with silver plating is that you have to use a lead free solder. Lead free solder looks silverish which helps with blending it to the silver plating. The difficulty with lead free is that it has a much higher melting temperature. 550/600F compared to 350/400F for regular soft solder. This makes it difficult to evenly heat the parts to the correct temperature because when you go to heat the other side of the part, the part you just heated will cool to below flow temp. Then the solder partially melts and turns clumpy/chunky and doesn't flow correctly into the joints, it just clumps up on the surface. Also when soldering parts with a lot of mass like the receiver or the valve casings, they take a long time to get up to temperature evenly and sometimes melts the solder in the wrong joints and that's when parts start unsoldering themselves. Also silver plating can burn. With all that being said I was able to rebuild this horn without any major issues.
           

     This is a Getzen Eterna, Doc Severinsen model, pro horn. At first glance it doesn't look so bad until you discover the abundance of red rot. The 3rd valve was jammed/stuck and I had to tap it out using what was a drum stuck at some point. After getting the valve out I discovered that the piston itself was bent, and that the casing was no longer true/round. So using a valve mandrel I was able to burnish the casing true again. Then using a flat steel bench block find the fulcrum point of the bend in the piston and slide it through the bottom of the casing to the fulcrum point and tap it down until it was dead straight. The valve now works pretty well however, it needs a full valve job because there is severe scaling of the pistons with nickel plating raised up and missing in spots. However, that's next semester when we go back to advanced brass repair.

                                                                                                                       The next issue was the stuck 1st, 2nd, and 3rd slides. The 1st and 2nd slide came out with penetrating oil and some encouragement from tapping on a drift punch that was snug up against the crook. The 3rd slide proved to be much more difficult. Just like the first 2 slides I used pt oil and the drift punch but there was no movement, and the crook started to collapse because of the amount of red rot. After 4/5 days of pt oil, hitting it with heat from a torch, putting it in the freezer in the teacher's lounge, chem washing it, putting it through the ultrasonic twice, and tapping on the crook with the punch, I finally had to resort to unsoldering the crook and the spanner brace. I was able to put an expander in the upper tube and with heat tap it out. The bottom however refused to move. So I soldered an old horn mouthpiece into the tube so I could get a better grip on the tube without destroying it. Using pliers I was able to heat it up and after hours of tapping and twisting, the tube finally came out. The brass from the inner tube started to bond with the brass from the outer and the red rot only made it worse. Eventually I got all slides out without damaging anything other than the rusted crook which would have been replaced anyway.

    Rebuilding the 3rd slide did prove to be quite the task and ultimately lead me to invent a nifty little device. On trumpets, particularly pro horns you want the 3rd slide to slide with very little resistance. It is very difficult to get the perfect slide action, particularly because of the spanner brace that is holding the tube together. When solder cools it condenses pulling the 2 tubes closer together making the tube fit too tight. So the teachers had me using pliers to try to spread the parts while soldering with the other hand. The problem with this is that you only have one hand to solder when it's generally a 2 hand job. The other issue is that your guessing how much pressure to apply to spreading the pliers. Also pliers get in the way and can harm the parts because of its small surface area at the point of contact. So I came up with a simple device to solve all these issues when building slides. This is a homemade slide tube expander. Just tighten the wingnuts and the steel plates expand evenly and precisely with small increments to help get just the right fit. The best part is that you can tighten/loosen them while the slide is in the horn to get the resistance that you want, solder, and know that when you take off the expander the resistance will still be the same.

     Here it is complete. The slide action feels great! After buffing the brass and putting on the old Amato waterkey, it looks really good. Personally, I like the gold on silver and it sure looks and works much better than when I first got it. Remember, this is the same slide that took almost a week to get out. When putting on the old Amato waterkey on the new crook I made sure to drill the hole bigger than the original because the issue w/ Amato water keys is that they don't evacuate fast enough because they hole is too small. I had to take off and resolder the Amato waterkey on the main tuning slide as well because it was put on backwards.

     As you'll see in the picture on the left, the outer lower main tuning slide is flared out at the end. Also the reinforcing stop ring has come off and  actually split. Using a trombone mandrel to support the tube from the inside I burnished and tapped the flair down to size. Then I soldered on a new ring making sure not to get any solder inside the tube. Success.. 

      The second slide had a nasty dent on the crook as well as missing the drawknob. The crook also had red rot. When pushing out the dent with my crook dent rod, the metal started to tear because it was so weak with rust. Using a sheet of silver nickel which, is extremely hard, I cut out a patch that would cover all the compromised metal. I annealed the patch 7 times to about 1200F, each time going back to rounding it out to shape using a form fit mold and a dent ball rod. I also pickled it, sanded it, and buffed it to smoothen out any raises and imperfections in the metal. Then had to heat and evenly tin the inside of the patch because I annealed it so much that the heat varnish oxides on the metal are just too thick for the solder and flux to bond to the metal. Then sanded down the edges and tack soldered it in the middle of the crook. I burnished from the top down to smoothen out any excess metal and soldered the patch on. Then I soldered on the draw knob which is never easy when using a lead free solder, and soldering 1 MM away from a solder joint.    

   

 The first slide had 3 small crook dents and was missing a draw knob. I used a little trick where you flatten a small piece of solder and pin it under the drawknob using a drawknob clip and a poker. You just heat up to temperature add flux and it basically solders itself. 

     The trumpet had a number of dents in the bell including one on the steam that actually caused the bell to bend up and out as you can see in the picture. It also caused the casing to bell brace to break at one of the silver solder joints. These were difficult to repair because the bell was extremely hard. Do to the broken brace and the severe dents in the bell tail I had to remove the bell completely which includes 6 solder joints. Long story short I used the Roath tool to take out the dent in the bell bow. Using a trombone slide mandrel I tapped and burnished out the dents. Using a trumpet bell mandrel, a dent roller, and                                                                                                 an arsenal or burnishers and dent hammers I was able to restore the bell.

       That bar in the picture below is a temporary cross brace for support when straightening the bell.

     As you can see in the picture above the old lead pipe was riddled with red rot from the inside out. Prior to removing the old leadpipe I made sure to measure all the specks. Then I unsoldered the finger hook, the two "S" braces, the leadpipe to casing brace, the receiver, and the outer main tuning slide. The new leadpipe is nickel silver so it should go a very long time without any red rot. The receiver and the outer main tuning slide weren't a tight enough fit. Filling a solder joint with a lot of solder is difficult because it can very easily get off center. Also solder joints with too much solder get weak. So I had to use simm, which is basically really thin sheets of brass to fill in the space. After measuring and getting everything centered I soldered on the old receiver and outer tuning slide. Then aligned the leadpipe and soldered the leadpipe to casing brace and the leadpipe to the brace. Then I soldered on the old finger hook. This was difficult because the finger hook needed to be soldered onto the leadpipe/outer tuning slide solder joint. It is difficult to get everything up to temperature without messing up the leadpipes solder joint. I was ultimately successful and amazed of how much solder it took. Look at those beautiful solder joints.

   





































    Then my next task was to reinstall the newly straightened and dent free bell. Soldering the bell was one of the most difficult task so far. It incorporated soldering 8 joints. It was a lengthy task but it was worth the time spent. The "S" braces were difficult because they were bent when the bell originally got damaged. So configuring them to fit to the bell/leadpipe without any gaps was tedious. The "S" braces cup in the middle and required a lot of solder to fill, which is always difficult. But just look at that soldering job.      

     I am very happy with the outcome of my solder job. Remember, you can't buff away extra solder/tinning like regular brass horns because you will buff away the silver plating. The trick is limited solder and very small, hard to see feed points.

After getting everything together and cleaned, getting the slide action just right, test play it, and hand polish it, I get to sit back and see that all that hard work paid off.

        Other projects

  One of our projects was to build a first slide from scratch. Then buff and lacquer it. 

  Another project was restoring bell buckles. Using a bell forming iron, a dent roller, and a number of mallets and burnishers I was able to restore the bell to almost new again. They call this kind of bell buckle the witches hat because of what it looks like. Look at those sharp twisting dents in that bell.

Some of the other projects that I was unable to, or forgot to take pictures from includes: Slide dents, bell folds, bell flair dents, bell steam dents, bell bow dents, crook dents, knuckle dents, leadpipe dents, and restoring mouthpieces by burnishing them in the bench motor.

    We also had to practice taking off, resoldering, and buffing a finger hook.

Tools

On the top is a custom built crook dent rod. The bottom is a custom built "Nose picker" for removing  dents in the leadpipe. It also works on many other types of dented tubes. 

                     

Inner tube mandrel, cut down to a precise size using a lathe. Done by yours truly. Then I center drilled it and tapped/threaded it.  

More pictures coming soon of the other tools we've built/customized so far this semester.