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  1. #1
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    how to make trenchart

    does anybody know how they used to put the deep flutes and twists in the shellcases?I put one in the 150 ton press today but it didn't go very well!

  2. #2
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    A long armed beading or swaging machine or Jenny but probably has a proper name, the one we used at work was known as the groover as it's main job was to run up and down the grooved joint on copper steam pressure boilers and had interchangeable wheels including some for putting ribs down a tube.
    The other way is pitch and ball punches, but perhaps someone has other methods.

  3. #3
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    Could the cases be pre grooved/creased in some way so that they follow the shape of the creases when outside pressure is applied,or were they swaged in by some sort of machine similar to a hydraulic pipe swager,I would assume that part filled with sand and sealed and pressure exerted on the outside of the case in certain areas with the use of shaped dies would lead to uniform creasing/fluting,would heating the brass almost red make the flutes easier to form with the brass being made soft,I would imaging some of the elaborate "trench art"was made in workshops and the more simpler versions made "at the front",I have a WW1 18lbr,case that has been bulged outwards to form a sort of trophy cup,the handles are made of driving band,the brass is beaten very thin and has cracked in places over the years,
    Cheers,
    Don,

  4. #4
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    thanks for the ideas,not sure what pitch and ball punches are.i agree that only the basic engraved type ones would be made at the front the other fancy ones requiring machine work could only be made back at the workshop areas.

  5. #5
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    Silversmiths use hard bitumen filled inside the object when they make for example coffee cans with similar decorations. Then they just use a small hammer and various punches. At the end the bitumen will be melted off. I think this is has the case for trench art as well, no need to use heavy machinery.

  6. #6
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    The original method of working the 'corsetted' shells was to fill the case with molten lead. The metal worker then used a half moon shaped punch and hammer which was progressively worked repeatedly around the case, going deeper and deeper as they went. As the case is worked the lead starts to poke out of the top of the case. This is a long slow process. The opposite of a 150 ton press!

    When the case was completed the case was heated and the lead poured into the next shell to be worked.

    The lead allows the brass to bend but adds support so it does not split. The bitumen is a more healthy option but in WW1 there was lots of lead around.

    John
    Author of 'British Rifle Grenades of the Great War'

  7. The Following User Says Thank You to Millsman For This Useful Post:

    beihan62 (1st December 2015)

 

 

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