At the risk of being repetitious, here are some answers to your questions: 1. Corrosion. Yes, corrosion is a valid concern. The buildup of green gunk inside the horn used to be part of it. If the horn is de-zincified (indicated by small pinkish spots with a dark spot in the middle) it may require extensive part replacement or be a write-off. Note that horns with dezincifiction can often be played for years before actual leaks or cracks develop. The best protection against corrosion is to keep the horn clean and oiled. It's good practice to put a few drops into the mouthpipe and blow it through the horn.
2. Valves. I'm skeptical about the claim that the valve was replaced. How was this established? I'm also skeptical about the idea that Knopf can replace the valve with an exact match. Depending on the age of the instrument, the valve set could have come from a number of different sources, none of them Knopf. Unless the horn is of current manufacture any valve replacement would be a hit or miss affair. In the event the valve was replaced you would still have an old, worn out valve set, in need of rebuilding. Just replacing the valves can't account for wear of the casings. This is a job for a repairman, not a builder. 3. Shipping. If you did decide to send the valves back to Knopf I'd suggest having whoever is doing the screw bell conversion take the bell off the horn. Then you would have a musical instrument part, a valve set, not a musical instrument. What's it worth? Not much. In the unlikely event you were charged duty in either direction it would be minimal. Mark the forms "Musical instrument part being returned to manufacturer for repair" and ship either by International Priority Mail (about $50) or UPS (about $170). UPS would allow you to insure and track your shipment. We've been sending stuff all over the world by post for years and they haven't lost anything yet. 4. Bell rings. Dick Merewether had it right when he said that everyone agrees that converting a horn to screw bell changes it, but no one can agree on what exactly it does. My experience has been that after a few weeks it reverts to being pretty much the same. We like and recommend E. Schmid rings for two reasons. 1. They are relatively small and light and, 2. they open up the possibility of using a wide range of after-market bells in different sizes, alloys, etc. Schmid's bells have a unique advantage over those of other makers: you can actually get them. The other primary choice would be an Alexander ring. In return for all this valuable free advice, let me take a minute to direct your attention the fact that we here at Osmun Music rebuild rotary valves and convert horns to screw bell. (FYI-we just got in a big shipment of flight cases). Personally, I think our mouthpieces are pretty good, too. Regards, Bob Osmun www.osmun.com On Fri, Mar 26, 2010 at 5:03 PM, <[email protected]> wrote: > > > I have questions concerning four topics, but first the set-up story... I > recently got my hands on an older Knopf compensating double horn. I had some > minor repairs done and, after adjusting the first valve, it felt a bit stuffy > but otherwise played very well. I've played some pretty nice instruments that > can be described as 'forgiving' or 'obedient,' but this Knopf actually seems > 'willing' to play what I want. Creepy, huh? I'm anxious to see how it plays > once it's issues are resolved. > > Corrosion - I had the horn professionally cleaned. The inside was filthy. The > slides fit well and there was/is no evidence of corrosion on the outside of > the horn. Is corrosion on the inside of the instrument a valid concern? If > so, how can this be checked and, if necessary, remedied? > > Valve work - During the cleaning it was discovered that the first valve had > been replaced with one that doesn't fit correctly. I contacted Christian > Knopf about getting a valve for it. He has been very patient with me and my > poor German generated by a web-based translation of iffy English. He > understandably wants me to send him the horn so he can correctly install the > right valve. My gut feeling is to ship the horn to him for this work. Does it > make sense to send the instrument to Germany to have the work done by Herr > Knopf? Can I have the horn properly repaired stateside, if so by whom? > > Overseas Shipping - If I send the horn to Herr Knopf, obviously I have to > ship it to Germany. From what I've gathered, shipping the horn overseas is > quite costly in time, money or both. The people at one shipping office raised > concerns about being taxed on the value of the horn getting it through > customs. Could someone with transatlantic shipping experience offer some > tips, please? > > Also, if all else works out, I'm considering having the bell cut. I prefer a > cut bell for ease of travel. The bell of this horn is so light and resonant > that I fear a ring might dampen it. I asked Herr Knopf and he said the bronze > ring he uses would not change the character of the horn. I've had screw bells > on my Paxman 20L and Yamaha 667V. The Yamaha ring seems to be by far the > lighter of the two. What are the differences in the rings available? Would > one be more appropriate than another for this horn? > > > > Doug > > Life is a terminal disease - live with it. > > > _______________________________________________ > post: [email protected] > unsubscribe or set options at > https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/rosmun%40osmun.com > > _______________________________________________ post: [email protected] unsubscribe or set options at https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/archive%40jab.org
