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Glass riddle

  1. Nov 11, 2007 #1
    Bought these two glass bulbs at a local art fair, the other month

    [​IMG]


    [​IMG]

    Size and shape as in Christmass tree balls, of hand blown glass but with a complex delicate glass object inside.

    Looks like ship in a bottle, but how do you get an object like that inside during the glass blowing process?
     
    Last edited: Nov 11, 2007
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  3. Nov 11, 2007 #2

    turbo

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    You can first produce a glass sphere (the easiest shape to blow) or cylinder, cut it open, insert the ornament and reheat the shell to melt the tips of the filaments on the ornament and seal the bulb.
     
  4. Nov 11, 2007 #3

    DaveC426913

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    I don't think they cut the bulb open to insert the ornament.

    I suspect they keep a hole open in the end of the bulb and build the ornament within it.

    One piece of evidence of this is that, if they could build the ornament free of the constraints of the bulb, it would likely be a MUCH more complex and skillfully made ornament. The fact that the ornament is quite ... freeform ... suggests to me that the creation process is extremely compromised - like, say because they're being constructed ship-in-a-bottle-style.
     
    Last edited: Nov 11, 2007
  5. Nov 11, 2007 #4

    turbo

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    Look at the top ornament and notice the flattened thicker glass at the top right. That's probably where the initial bottle/bulb was opened. They would have to use a large opening to insert the ornaments with all those thin glass filaments. Then as they reheated the bulb to reform it and seal it, the bulb contracted against the tips of the filaments and melted them.
     
  6. Nov 11, 2007 #5
    I sort of agree with you---to add a little---it may have been a tube of glass where that inner item or really the hobnails of it touched the inner walls, when the tube was reheated, one end closed, and blown to expand to become round, the expansion pulled the hobnails that had attached to the inner walls to string--then the end was closed.
     
  7. Nov 11, 2007 #6

    Moonbear

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    I wonder if it's more that they used something with a slightly higher melting temperature for the inner "glob" and surrounded it by the glass before blowing to get the glass to stick to some of it. Those fine spindles attaching the glob to the sides look way too thin and in the second one, too numerous, to have been placed individually in a cut piece.

    Of course, we wouldn't have to be guessing if Andre had just asked the artist when he bought them at the fair. :biggrin: I've never had trouble getting an artist to tell me more about their work at an art fair...I have had trouble getting them to STOP telling me more about their work.
     
  8. Nov 11, 2007 #7
    he probably did---and just want to check how far we can be off with 'guesses'
     
  9. Nov 11, 2007 #8

    Moonbear

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    Now that sounds like the best explanation so far. Start blowing the globe, then insert the center part when there's room to get air around it to only blow the outside, but still small enough to allow contact.

    I wonder if the rest of the artist's collection had a lot of green glass in it, from remelting all the ones where the inner piece didn't stick where it was supposed to. :biggrin:

    I like how the first one looks like pickles inside it.
     
  10. Nov 11, 2007 #9
    I knew and hung around a glass blower 'artist' ---amazing use of the plasticity

    --------------

    I have a small collection of art glass too, and have read about Tiffany, Loetz, Pairpoint, etc.

    ---------------

    I've tried to make some stuff--all you need is some tools and a propane torch
     
    Last edited: Nov 11, 2007
  11. Nov 11, 2007 #10

    DaveC426913

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    Question: if they were going to insert the inner piece in anything like partly-assembled condition, there would be virtually no limit on how much care and attention they could put into it before inserting. Instead of an amorphous blob of colour, why wouldn't they be inserting fully fiinished pieces like hummingbirds and beautiful flowers? I mean, that inner shape, - if you took it out of the bulb thus and out-of-context - is not exactly state-of the art blowing.
     
  12. Nov 11, 2007 #11
    it came out of an art fair --not an art gallery---those may not have cost more than $20-30 each---I bet the artist did have more expensive items, too
     
  13. Nov 11, 2007 #12
    No, she was happy to talk a lot but not how she did it. The only thing the artist told that she needed some 15 years to get to this result. She showed earlier work in which the fibres connecting the bulb with the ornament clearly distorted the round shape quite a bit.

    These were among the first 'round'ones.
     
  14. Nov 11, 2007 #13
    then, she may have had to find a way to shrink/vacuum the tube down against the hobnails--then, when connected to the inner walls, enlarge and pull the fibers making the threading in the ball --all while not melting the fibers and still hot enough to be able to blow it into a ball shape
     
  15. Nov 11, 2007 #14

    FredGarvin

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    My guess is that the inner part was a small "billet" of glass that had the outer glass wrapped around it at the end of a tube. The tube would have an inner and outer flow path. The two are heated together to make them flow. Air is introduced in the outer flow path to get the outer sphere to start growing. Air is then introduced into the inner at a slower rate.

    I am guessing that the strands that go from the inner to the outer surface are created while still hot by poking a sharp tool through the outer and into the inner part. The tool is then pulled back out, pulling the inner strand with it.

    That's my guess anyways.

    Those are really cool looking ornaments. My wife would LOVE one of those.
     
  16. Nov 11, 2007 #15
    okay i'll see if I can trace her back and see what's possible.
     
  17. Nov 11, 2007 #16
    I think they're beautiful, especially the top one, which has a kinda venus fly trap thing going on, and I can see that the fibers attached to the inside wall must be a very difficult effect to achieve.
     
  18. Nov 11, 2007 #17

    DaveC426913

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    I suspect that you're right about the first part (two concentric layers of blowing) but that the strands are made by inserting a molten rod of glass in through the neck, then letting it touch the inside and stick and then pulling it away.
     
  19. Nov 11, 2007 #18

    turbo

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    I think that the inner decoration was pieced together with glass rods extending from all directions. The initial envelope was opened to insert that decoration, and then the envelope was reheated. Such an envelope will contract due to surface tension unless the glass-worker can blow into the envelope and expand it. Once the envelope (bulb/enclosure) is sealed on the open end, the artisan can continue to heat it so that the envelope bonds with the glass rods projecting from the inner decoration, and gently blow it while heating to take advantage of glass' viscosity and draw out those thin filaments.
     
  20. Nov 11, 2007 #19

    Moonbear

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    Maybe she hasn't gotten that good at it yet. :biggrin: Or, maybe putting something more "shapely" into the center doesn't work, because it melts partially and loses its shape. Or maybe she just liked the amorphous blobs better than something like hummingbirds and flowers. :biggrin: That could be why she sells her "craft" at a fair instead of at a gallery, because she's not good enough at it yet...some people at art fairs really are artists, others are more crafters who do these things as hobbies, so not enough to open a shop or sell them through other venues. Obviously, enough people like them to buy them, and that's really all that counts in the end. I'd have probably skipped them because they look too fragile to survive my not-so-tender loving care, or the cat who is already plotting to attack the Christmas tree when it isn't even set up yet, :uhh: but I think otherwise, I'd rather have an interesting, amorphous "blob" than a cliched hummingbird or flower. So, I could see it going either way, that she chose the more amorphous approach because her skills aren't yet sufficient to accomplish better (glass blowing can take decades to master), or because she just found it more aesthetically appealing for its uniqueness.

    It would be cool if Andre is able to contact the artist and find out more about the technique or reasoning behind the choice of center.
     
  21. Nov 11, 2007 #20
    These kinds of glass orbs are several hundred years old, and are known as Witch Balls.
    It was thought that a witch entering the home, would be so inraptured by them that the evil soul would be cought up in them, and trapped. It was common to find them hanging in windows of even the poorest homes. The antique balls sell for hundreds of dollars, new ones around 30.
    Andres, is very nicely made, to keep in mind how hard it is..remember that blown glass has to kept spinning on the pontil !!!

    Here's a look at some colorful ones.

    http://www.whiteelks.com/witchball.htm
     
    Last edited: Nov 11, 2007
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