Restoring Holton Cornet

Discussion in 'Vintage Trumpets / Cornets' started by BrassBandMajor, Dec 24, 2016.

  1. BrassBandMajor

    BrassBandMajor Fortissimo User

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    Well, I pulled out my 1952 Holton Collegiate Model Cornet from the lonely cellar with the other Chinese horns who live snuggly together on a wooden rack. The battered case was a real question what to do with, throw it away or keep but anyway I got my mini clamping vice and did a list of things to do.

    Today was the start of the restoration of my Holton Cornet.

    Generally, its like one of those beat up school cornets, but no dents. Its got severe red rot in hand-held positions with majority of the horn with wear (needing a re-lacquer job). The Holton Cornet had a minor leadpipe bend and I suspected tension was holding on the left side of the brace. So, after today's shopping involving a new bottle of Newport extra-purified gas for lighters, I lit up those torches and put them in action. For the first time in my life, I removed one brace from a cornet. It was a good success took a few posts by stumac on trumpetmaster threads on un-doing braces and I was ready to go. After the brace was removed, the leadpipe somehow reverted into a straight position, so the one major tension area was cleared.

    I did not have much time tonight so that was what I did and freed all slides and valves. I ordered a build kit for the cornet, (felts, springs, corks and etc) because the cornet was in need of valve springs (someone took them away) :-(
    AND one other thing I did was, to polish the tuning slide with MAAS and got that shine back.

    PHOTOS TO BE ADDED. :-)

    Very excited, I hope one day the 'chosen' cornet will come into my hands for its restoration but I think I will need to practice a few years.
     
  2. Clarkvinmazz

    Clarkvinmazz Forte User

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    Are you sure it's redrot? Hand hold positions are not places where redrot normally happens.
     
  3. OldSchoolEuph

    OldSchoolEuph Mezzo Piano User

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    I think you hit the nail on the head with your last sentence - As with all things relating to these horns, practice is paramount!

    You mentioned red rot at the contact points, which would be unusual except at the thumb contact on the leadpipe. Red rot is acidic conversion of the brass alloy that results in loss of material and eventual pin-holes from the inside of the tubing to the outside (with some impressive cratering on the inside that leaves the pipe weakened so that it shatters under stress). In other posts, I came to wonder if you are confusing surface acid staining, typical if an owner has a more acidic body chemistry, or if the horn's lacquer fails and it is stored in an acidic environment. I am attaching a picture that Robb Stewart sent me, and I added text to, which shows early red rot with the classic clusters of dots with their pinpoint black centers.
    Early red rot.jpg
    Next is a picture of a horn with one classic red-rot pink dot by the pinkie-hook and also dotting on the bell that is simply the Martin lacquer starting to flake off. If it were in an acidic environment, the lacquer loss would be pink too, but not in the same bulls-eye way.
    lacquer vs redrot.JPG
    Finally, what I think you have been confusing with red rot, the bell of a 1952 Conn that lost its lacquer and was either cleaned with an acid, or stored in a place like a basement workshop that had acid in the air (maybe muriatic acid was stored nearby as a cleaner?). This is a thin layer of alloy conversion just on the surface and does not impact the horn other than in appearance. If the brass is thick enough, it can be polished off without harm (though I would hesitate to buff a bell that hard).
    Conn 1952 22B Bell.jpg

    Good luck with the restoration. I look forward to before-and-afters here.
     
  4. Dennis78

    Dennis78 Fortissimo User

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    Make sure the rebuild kit is for bottom sprung valves.
     
  5. BrassBandMajor

    BrassBandMajor Fortissimo User

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    Update 1*

    Today was an important day.
    I removed all the lacquer and the red stuff went away together so it wasn't red rot......
    Anyway, flakes of lacquer went and I did a light polish of MAAS on the bell with a buffing rotary tool and wow, what a stunner.
    I am so excited to see what the result will be.

    Since the leadpipe was bent, the day before I removed the brace connecting the pipe and the bell. So today I soldered it on again.
    I removed one small knob from the 1st slide so that I can solder on a 1st slide hook for the collegiate tomorrow.
    I also plan to do the same with the 3rd slide. :-) Its an experiment, if its bad, I will remove the finger hooks but we'll see.
     

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