What's it for?

Discussion in 'Trumpet Discussion' started by crowmadic, Nov 15, 2007.

  1. crowmadic

    crowmadic Mezzo Piano User

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    Oct 3, 2006
    I'm going to call it a Valve Guide. It's the part of the valve that sits in the notch in the casing, and the spring rests on it. On my "vintage" horns most of those guides are made of brass, and and have a little screw on it. What is that screw ment to do?
     
  2. MFfan

    MFfan Fortissimo User

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    Sep 13, 2006
    Kalamazoo, Michigan
    That's a good question, Crow. I have a couple of older cornets, 61 Roth and 53 Holton that have those, although they look like silver stainless. Their valves are bottom sprung. I was just contemplating that yesterday while trying to reduce "stickiness" on my Holton Collegiate's ist valve. Somebody out there will know!:-)
     
  3. crowmadic

    crowmadic Mezzo Piano User

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    Oct 3, 2006
    MFfan, what are you doing to reduce stickiness?.......crow
     
  4. MFfan

    MFfan Fortissimo User

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    Well, aside from praying alot hoping for devine inspiration I have tried a number of things.
    1. change valve oil type
    2. put in household 3-1 oil
    3. vigorously move the piston up and down for a while, as in fast playing.
    4 look for obvious defects.
    5. Alter angle of finger attacks.
    6. Consulted with my friend, OLDLOU, who suggested trying to insert the 2nd valve into the ist sleeve to see if it moved smoothly and try to insert the 1st in the 2nd casing, which it wouldn't take past the valve guide. The second piston worked without sticking the the 1st casing, so he felt it must be some defect or wear in the piston. It does have some wear marks.
    Haven't resolved the issue as yet. Thanks for asking
     
  5. crowmadic

    crowmadic Mezzo Piano User

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    Oct 3, 2006
    MFfan, Please let us know if you correct the problem and how you did it.
     
  6. MFfan

    MFfan Fortissimo User

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    Kalamazoo, Michigan
    After more email talk with Lou, I took photos of the valve piston in question and sent them to him, first, on his suggestion, pulling the valve out straight and try to determine if any observable wear could be lined up with the interior 1st valve tubing, which might indicate some abnormality there that could hang up the piston. I couldn't definitively connect anything there. He reviewe the photos and noted the bottom of the piston was "galled" It does have a scraping pattern around the bottom sides of the piston all around extending a very short distance upwards. One of his other ideas was that the valve casing could have been slightly damaged and causing a hang up, but I don't see any.
    Anyway he wants to see it personally and compare it with the pristine valve of his Collegiate cornet. Turns out mine is bottum sprung and his is top sprung. We are meeting Monday at a location equi-distant and will go from there. There is some wear patterns of different sorts on the piston, but I don't know what they indicate. Will report further. There is no problem with the other valves on the horn. I will ask him about the screw. Maybe he will see this post and respond. Dave
     
  7. crowmadic

    crowmadic Mezzo Piano User

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    Oct 3, 2006
    Dave, I'm so glad you're going to ask him about the screw. I would have thought someone on TM would have answered this by now. I just did a "ballsy" thing that I might do with valves I can't get to stop sticking or dragging. I went ahead and bought a lapping tool and some lapping compound and used them on an old Olds Ambassador Cornet that needs a lot of work. The middle valve only went 1/3 of the way into the valve casing. First I took the lapping compound, smeared it on the valve as directed, and worked the valve in and out. I made some headway but not enough. After washing the compound off of the valve and the casing I inserted the lapping tool and expanded it without trying to cut any metal. There was an immediate improvement which lead me to beleive the valve casing was out of round or had some obstruction. After doing this from the top and bottom of the casing the valve went into the casing properly. Of course the objective is not to overdo it. But I can tell you that I wouldn't hesitate to do this again on any horn that gives me a valve problem that can't be remedied by other means. I wouldn't try this on extremely expensive horns. I'd leave that to the experts................let me know what you find out about the screw.........crow
     
  8. MFfan

    MFfan Fortissimo User

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    Crow, I see from your other post you and I are the same age. I have been playing in one group or the other or several since I started in 55. Belong to a fine concert band here in Kalamazoo. I admit ignorance to anything lapping, lapping compound or tool! Since I joined the forums last year I have found I knew little or nothing about much of anything trumpet. I'll bring that up to Lou and see what he says about that idea for my situation, and also about the screw.:D
     
  9. crowmadic

    crowmadic Mezzo Piano User

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    Oct 3, 2006
    that's the right thing to do MFfan.........crow
     
  10. Brekelefuw

    Brekelefuw Fortissimo User

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    Mar 21, 2006
    Toronto

    Lapping is taking material away from the valve casing or valve, so be really careful and make sure there isn't another fix. If the valve slides ar damaged it could be as simple as bending them back to their original place so the valve casing straightens out.
     

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