About flute repair at Rich Lupo
This page is going to get pretty technical. Most flutists are not going to understand all of this, but I think it is valuable to be fully transparent on my repair techniques, on what I do and don't do. Other professional repair technicians can read this and verify that I know what I'm doing, and perhaps learn a thing or two. There are many different schools of thought and different techniques for flute repair. Some of them are quite bad. My methods are based on years of experience and training and best practices developed by the flutemakers themselves, combined together.
Even with over 20 years of experience, education is never-ending in the flute repair industry. We all study with each other, learn from each other, and borrow techniques from each other. We experiment to find what works and what doesn't work.
My repair style is best described as a combination of Tom Peterson's style and Flute Center's style, with some modifications based on what I've experienced to work best for me and my clients.
Emphasis on Quality. It comes above all other things. Quality is more important than speed, profit margins, convenience, fads, appearances, or ego. All my techniques are chosen or abandoned based on quality.
Shimming technique: Preference for plastic shims in overhauls. Both whole and partials are used. I begin partial shimming at .001" with plastic, or .002" with paper and I do use .0005" mylar shims on all types of pads. For paper shims the partials are glued to the base shim, not to the back of the pad. For plastic partial shims I "glue" them to the base shim with grease. I do not mix paper and plastic shims. The base shim and the pad are marked at 12. I typically use about 10 partial shims per pad, sometimes less, sometimes a lot more, whatever is needed.
Cup settings: Aiming for .014" protrusion of the pad from the cup to prevent dishing. Stabilizers are used whenever possible, strong preference for brass or aluminum, glued in to the cup. I will tip keys to straighten them before shimming. I will adjust the cup setting if possible depending on the brand of flute, or spacers will be used under the washer to prevent the pad from dishing. I will always screw the pad screw on tight, and the bushings will be pushed in all the way. With a straight key, flat pad, and flat tone hole I will use base shims to get the lightest-touch, perfectly-even contact at 12 and 6, and 3 and 9. Then I use partial shims for the rest.
Leak locating: I use .0005" feeler guage material, a leak light, a mag machine with the leak isolator, and playtesting. I use an extremely light touch, pushing on the opposite side of the key from where I am feeling. I have specific low numbers on the mag machine which I work towards, to create objective standards of quality.
Tone holes: I will very lightly level tone holes if they are not flat. If the tone hole dips are larger than can be fixed, shimming can make the pad seal.
Seating the pads: On flutes with felt pads I will very lightly seat them after shimming. On beginner/intermediate flutes I will seat the pads a bit more, and I expect to use fewer partial shims, perhaps 3 per pad.
Spring tension: I like a nice, lightly sprung flute. I will adjust spring tension to the most desirable level, which means I might lighten some of your spring tensions. If you don't like it, I can adjust it back for you, but I recommend you try my suggestions. If you have specific requests on spring tension, please let me know before I work on your flute.
Mechanical restoration: I will swedge, ream, straighten, and of course clean and oil the entire mechanism to provide the most consistent mechanism possible.
Headjoint corks: I sand the cork to a tapered shape. I glue the cork to the cork plate and also the top nut. I coat the cork in wax. For piccolo headjoint corks I like to position the cork for the best tone and response of the middle register, rather than the line on the cleaning rod. The effect on intonation is negligeable but it can make a huge difference for the middle register, so I prefer to determine the piccolo headjoint cork position this way.
Polishing: I only hand-polish, no machine polishing. I use the pink dip to remove tarnish and then hand polish with simichrome. For a COA I will lightly wipe the tops of keys and the rods with a polishing cloth but I won't polish the sides of the key cups to prevent damaging the pads. On overhauls I like to make everything shiny. For silver-plated parts I may be more delicate to preserve the plating and it may not be possible to polish those parts to a like-new shine.
Playtesting: As a professional flutist I playtest every flute extensively, with a very light touch. I will usually have my wife playtest the flute also for a second opinion. I will not finish working on a flute until it plays perfectly for everyone who plays the flute, especially the owner, who gets the final say. I am happy to keep working if the customer feels it is not to their satisfaction yet, when they play it. This is extremely rare as I tend to be much more picky than my customers.
Materials: I will use the high-end materials appropriate and industry-standard for the particular brand of flute, usually as originally designed or intended for the flute. I am not a fan of synthetic felt unless the flute brand uses it originally. Hat felt is ideal. On Japanese flutes I like using Muramatsu felt. Cork is great on piccolos.
Networking: I have many friends and colleagues in the industry, and I reach out for help and advice when I am not 100% sure of what is best, even though I have experience in virtually every brand of flute and every possible flute repair. I also assist my colleagues with advice when they ask me for help. I do not keep trade-secrets and I am supportive of the free, open exchange of information and knowledge in the industry.
Pads: I will use the most appropriate type of pad for each overhaul. I will not mix felt and Straubinger-style pads together on the same flute. Straubinger and Pisoni S2 pads are considered interchangeable though. (Most brands have switched to S2 pads lately.) Conversions from felt to Straub-style are possible, not usually recommended, but done on a case-by-case basis. I like to remove the sticker from S2 pads and lightly sand the backs, which makes them flatter and more stable.
Oiling wood instruments: I will oil headjoints during a COA, on an overhaul I will oil the whole instrument. If you have a nut allergy please let me know so I can pick an appropriate oil for you.
Even with over 20 years of experience, education is never-ending in the flute repair industry. We all study with each other, learn from each other, and borrow techniques from each other. We experiment to find what works and what doesn't work.
My repair style is best described as a combination of Tom Peterson's style and Flute Center's style, with some modifications based on what I've experienced to work best for me and my clients.
Emphasis on Quality. It comes above all other things. Quality is more important than speed, profit margins, convenience, fads, appearances, or ego. All my techniques are chosen or abandoned based on quality.
Shimming technique: Preference for plastic shims in overhauls. Both whole and partials are used. I begin partial shimming at .001" with plastic, or .002" with paper and I do use .0005" mylar shims on all types of pads. For paper shims the partials are glued to the base shim, not to the back of the pad. For plastic partial shims I "glue" them to the base shim with grease. I do not mix paper and plastic shims. The base shim and the pad are marked at 12. I typically use about 10 partial shims per pad, sometimes less, sometimes a lot more, whatever is needed.
Cup settings: Aiming for .014" protrusion of the pad from the cup to prevent dishing. Stabilizers are used whenever possible, strong preference for brass or aluminum, glued in to the cup. I will tip keys to straighten them before shimming. I will adjust the cup setting if possible depending on the brand of flute, or spacers will be used under the washer to prevent the pad from dishing. I will always screw the pad screw on tight, and the bushings will be pushed in all the way. With a straight key, flat pad, and flat tone hole I will use base shims to get the lightest-touch, perfectly-even contact at 12 and 6, and 3 and 9. Then I use partial shims for the rest.
Leak locating: I use .0005" feeler guage material, a leak light, a mag machine with the leak isolator, and playtesting. I use an extremely light touch, pushing on the opposite side of the key from where I am feeling. I have specific low numbers on the mag machine which I work towards, to create objective standards of quality.
Tone holes: I will very lightly level tone holes if they are not flat. If the tone hole dips are larger than can be fixed, shimming can make the pad seal.
Seating the pads: On flutes with felt pads I will very lightly seat them after shimming. On beginner/intermediate flutes I will seat the pads a bit more, and I expect to use fewer partial shims, perhaps 3 per pad.
Spring tension: I like a nice, lightly sprung flute. I will adjust spring tension to the most desirable level, which means I might lighten some of your spring tensions. If you don't like it, I can adjust it back for you, but I recommend you try my suggestions. If you have specific requests on spring tension, please let me know before I work on your flute.
Mechanical restoration: I will swedge, ream, straighten, and of course clean and oil the entire mechanism to provide the most consistent mechanism possible.
Headjoint corks: I sand the cork to a tapered shape. I glue the cork to the cork plate and also the top nut. I coat the cork in wax. For piccolo headjoint corks I like to position the cork for the best tone and response of the middle register, rather than the line on the cleaning rod. The effect on intonation is negligeable but it can make a huge difference for the middle register, so I prefer to determine the piccolo headjoint cork position this way.
Polishing: I only hand-polish, no machine polishing. I use the pink dip to remove tarnish and then hand polish with simichrome. For a COA I will lightly wipe the tops of keys and the rods with a polishing cloth but I won't polish the sides of the key cups to prevent damaging the pads. On overhauls I like to make everything shiny. For silver-plated parts I may be more delicate to preserve the plating and it may not be possible to polish those parts to a like-new shine.
Playtesting: As a professional flutist I playtest every flute extensively, with a very light touch. I will usually have my wife playtest the flute also for a second opinion. I will not finish working on a flute until it plays perfectly for everyone who plays the flute, especially the owner, who gets the final say. I am happy to keep working if the customer feels it is not to their satisfaction yet, when they play it. This is extremely rare as I tend to be much more picky than my customers.
Materials: I will use the high-end materials appropriate and industry-standard for the particular brand of flute, usually as originally designed or intended for the flute. I am not a fan of synthetic felt unless the flute brand uses it originally. Hat felt is ideal. On Japanese flutes I like using Muramatsu felt. Cork is great on piccolos.
Networking: I have many friends and colleagues in the industry, and I reach out for help and advice when I am not 100% sure of what is best, even though I have experience in virtually every brand of flute and every possible flute repair. I also assist my colleagues with advice when they ask me for help. I do not keep trade-secrets and I am supportive of the free, open exchange of information and knowledge in the industry.
Pads: I will use the most appropriate type of pad for each overhaul. I will not mix felt and Straubinger-style pads together on the same flute. Straubinger and Pisoni S2 pads are considered interchangeable though. (Most brands have switched to S2 pads lately.) Conversions from felt to Straub-style are possible, not usually recommended, but done on a case-by-case basis. I like to remove the sticker from S2 pads and lightly sand the backs, which makes them flatter and more stable.
Oiling wood instruments: I will oil headjoints during a COA, on an overhaul I will oil the whole instrument. If you have a nut allergy please let me know so I can pick an appropriate oil for you.
