When I cover bottom valve cap and press valve, valve comes back slowly. What is wrong

Discussion in 'Trumpet Discussion' started by jp554731, Nov 21, 2014.

  1. jp554731

    jp554731 New Friend

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    Dec 31, 2008
    So here are the symptoms of my first valve, when I press it, a burst of air comes from the bottom valve cap hole everytime. When I cover the hole, the valve comes up very sluggishly.
    This is the second mount Vernon strad trumpet I got like this. First one was the 3rd valve, now it is the first. Can't figure it out. All the slides are not stuck, there is no water trapped inside the valve, although I did wash the whole horn before playing it.
    is this a symptom of valves with leaking air? I noticed that there are some light pliers marks on the top valve cap. Could this be the culperate
    Although I can play the trumpet, I just find it rather annoying that I can't figure out the cause.
    Please educate me. Thanks
     
  2. Brekelefuw

    Brekelefuw Fortissimo User

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    Re: When I cover bottom valve cap and press valve, valve comes back slowly. What is w

    The hole is there for a reason. Your valve are not leaking air.
    You are creating suction by covering the hole. Air has to be able to flow in and out of the bottom of the valves so no suction of compression can occur.
     
  3. gordonfurr1

    gordonfurr1 Forte User

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    Re: When I cover bottom valve cap and press valve, valve comes back slowly. What is w

    I hear a vacuum developing...
    sort of.
     
  4. trickg

    trickg Utimate User

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    Re: When I cover bottom valve cap and press valve, valve comes back slowly. What is w

    Just a thought, but in the actual day-to-day activity of playing a trumpet, is this EVER going to be a concern? Valves are not 100% airtight. Are you expecting the valve to not come up at all? All of that aside, a common misperception is that air flows through a trumpet. It doesn't. (Air moves through the horn, but very, very slowly - the horn is a resonator for a vibrating air column) The tolerances for valves don't have to be super tight - in fact, they can be pretty sloppy and it won't affect that much in how a horn plays overall.

    My advice to you would be to simply not worry about it.

    I hear the same thing.
     
  5. Ed Lee

    Ed Lee Utimate User

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    Re: When I cover bottom valve cap and press valve, valve comes back slowly. What is w

    Usually when cleaning a valve by soaking, water and the gunk/residue from the outside may get inside the valve via the hole in the bottom of the valve itself. Until this is checked, dried and removed such is quite likely to produce "sound effects" and/or produce a touch variance to the feel of the valve when played. IMO, I do not recommend soaking a valve to remove the lubricant build-up on its outside surface. This can be addressed by outer surface cleaning of the with a grease solvent detergent on a wash cloth. Do not forget to clean the interior of the valve casing likewise.
     
  6. jp554731

    jp554731 New Friend

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    Dec 31, 2008
    Re: When I cover bottom valve cap and press valve, valve comes back slowly. What is w

    I was just worried since none of my valves on my daily player do this and the other 2 valves on both mt vernons were fine.
    So I take it, this is nothing serious.
     
  7. veery715

    veery715 Utimate User

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    Re: When I cover bottom valve cap and press valve, valve comes back slowly. What is w

    There MAY be a passage through the piston, which is actually a hollow cylinder with ports soldered into place: a hole on top and one in the bottom, to allow air to pass through it. This may be blocked. You can try blowing compressed air through the opening in the bottom* of the piston. The little hole on the top is often obscured by the spring cage.

    *The concave piece set into the bottom of the piston has a hole in its center.
     
  8. stumac

    stumac Fortissimo User

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    Flinders Vic Australia
    Re: When I cover bottom valve cap and press valve, valve comes back slowly. What is w

    My Mt Vernon has this problem in its 3rd valve, I think it is solder from assembly, I have tried to clear by soaking, blowing with compressed air, acid dip and pushing a wire through all to no avail. I think the manufacturer was generous with the solder, I have removed match head sized solder blobs from inside 2 of the valve slides.

    I would not worry about it.

    Regards, Stuart.
     
  9. jp554731

    jp554731 New Friend

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    Re: When I cover bottom valve cap and press valve, valve comes back slowly. What is w

    Thanks a lot you guys, this helped
     
  10. rowuk

    rowuk Moderator Staff Member

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    Re: When I cover bottom valve cap and press valve, valve comes back slowly. What is w

    This is kind of a common sense question - that is why it is curious that it was even asked. Google the word PISTON and you will see why it would actually be a good thing if ALL the valves did this. If you gave back a Mt. Vernon Strad because of this, someone is laughing his behind off!

    Tight valves respond to vacuum, leaky valves don't. That being said, there are a lot of people that don't notice or particularly care and even worse there are a lot of instrument makers that don't particularly care either. I would be more than willing to take that crap horn off your hands - after I sell you a bridge ;-)
     

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