Discussion in 'The Rehearsal Room' started by floral_dance, Jan 8, 2004.

  1. floral_dance

    floral_dance Member

    I know there has been a topic on valves before but I have a specific question, what does it mean when your valves are relapped back into their casings? I have been having problems on my sovereign cornet which is about 9 months old with valves sticking etc, I took it back to the supplier and they said they would try lapping the valves back into their casings, could someone please enlighten me? :oops:
  2. Seedhouse

    Seedhouse Active Member

    Lapping is when they use some method (which I apologise for not knowing! :oops: ) and it means that the valve casing is reformed to exactly match the shape of your valve. So basically if your valves are a bit naff it will probably help. I've had it done to a vlave in the past, and it corrected it greatly.
  3. BigHorn

    BigHorn Active Member

    Lapping is basically a posh name for fine grinding.
    Usually this involves the use of abrasive paste - often placed between the mating surfaces to ensure they are mated together properly.

    You could actually do this yourself by 'oiling' the valves with t-cut, brasso etc and pressing them up and down for a couple of minutes. I wouldn't recommend that though as you would be abrading parts of the valve/casing that dont need abrading.

    I imagine a proper job would involve using engineers blue to identify the high spots where the metal is rubbing and only lapping those spots. (Engineers blue is a special fine paper placed between the surfaces. When high spots rub on the paper it leaves a blue dye mark on the metal identifying what needs to be 'lapped'.)

    There you are - my old metalwork teacher would be proud of me for remembering that.
  4. floral_dance

    floral_dance Member

    Thank you very much. I am picking my cornet up tomorrow so hopefully I will notice a difference.
  5. Okiedokie of Oz

    Okiedokie of Oz Active Member

    My teacher suggested Ajax many moons ago
  6. Cantonian

    Cantonian Active Member

    This reminds me of a not very bright lad who was in the band years ago playing bass trom. He had a frost plated imperial and admired the brass lacquered trombone of a friend. He spent hours with sandpaper and a brillo pad taking the plating off, then used brasso to shine it and sprayed it with hair lacquer. What a mess!
  7. sparkling_quavers

    sparkling_quavers Active Member

    :shock: :shock: :shock: :shock: :shock: :shock: :shock:
  8. Highams

    Highams Member

    I have done lapping a number of times now on my older euphs. I collect, using watered down brasso, or a mixture of slate powder and water.

    Both these are quite effective, you only need a slight abbrasive mix to do the job, the worst bit being the warm bath afterwards to get all the mess out of the tubing again.
  9. Tromgod

    Tromgod Member

    I can understand wanting to destroy the Imperial but surely it would have been easier to place it behind a parked truck or something!?

    :hammer :D
  10. floral_dance

    floral_dance Member

  11. Seedhouse

    Seedhouse Active Member

    Hi, Floral Dance you haven't said how your valves are- since you got your instrument back. How are they?
  12. floral_dance

    floral_dance Member

    not any better I am afraid to say. I took my cornet back to band supplies on Saturday morning and they will send it back to Bessons. Don't know what they wil do but it is still under guarantee. The 1st and 3rd valves are brilliant but the 2nd valve just feels like it is going through treacle. It just collapses after a while. I have been given a loan of an old sovereign from band supplies until my cornet comes back and the valves on that is just wonderful. In fact I might just ask to keep a hold of it until the areas.

    I really hope my valve can be sorted, if not maybe they will give me another cornet!!!!

    Any ideas?
  13. Okiedokie of Oz

    Okiedokie of Oz Active Member

    My music teacher had an early model Sovereign euph (941 or something, I think....pre-flare) and used it to win state titles, nationals and even get into the Ern Keller. Then, at about the same time as I got my tuba, everyone was going out to get the new sovereigns, and he upgraded his euph. He practised on it thrice daily, plus using it as a teaching tool.

    Come the local eisteddefod (sp - stupid welsh words!), he got on stage and started doing A Philip Sparke piece (Party something, I can't remember) and his 2nd valve seized on him. It was just a case of not being worn in properly.

    My tuba, also when brand new, had to have the valves oiled daily at first for the first 3 months. Could it just be the same thing with yours?? Just thinking and typing here, really.
  14. floral_dance

    floral_dance Member

    My cornet gets played daily and my valves were oiled nearly every day for the first few months, but all that happened was a build up of oil. My cornet also must have been the most washed and cleaned cornet in Scotland, as I then started washing then oiling the valves every day. I have tried various things but to no avail :(

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