Message from discussion forming a large diameter tube

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Date: Mon, 08 Jun 2009 21:58:26 +0100
From: David Billington <d...@djbillington.freeserve.co.uk>
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Subject: Re: forming a large diameter tube
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Permafacture wrote:
> I was thinking about how to slump a large diameter tube from a flat
> plane of glass.  I have little experience with glass working and dont
> know to what degree this is workable...
>
> You'd take a piece of float glass, from like a window and slump it
> over a ceramic tube you made/found as a form.  Put it in the kiln and
> let it soften and after its really gooy pull it out for a second and
> use poles to roll the hanging edges together.  The maybe flip it so
> the seam is on top and put it back in the kiln.
>
> ?
>
> Is this at all how you would form a large diameter tube from found
> resources?
> What size kiln do glass workers usually have; what is the widest sheet
> i might be able to work?
> can it be anealed in the same kiln it was slumped in?
>
> thanks!
>   
I'm no expert but I have seen pictures of large tube shaped parts 
slumped from flat. The parts had a length maybe 5 times, from memory, 
greater than the diameter, so what you require may be possible without 
the roll up technique. The roll up sounds like the reverse of the old 
tcchnique for producing flat glass where a cylinder was blown and split 
an unrolled to form a flat sheet.