Frit-Happens !

Technical Forum => Search Tips and Techniques => Topic started by: jackiesimmonds on April 02, 2015, 09:46:58 AM

Title: draping query
Post by: jackiesimmonds on April 02, 2015, 09:46:58 AM
Thought I would post here as well as elsewhere since I notice that people seem to respond here so perhaps this is the board read the most.

I recently tried draping a fused piece of Bullseye, (2 pieces of 3mm fused together) hand painted with glassline paints in a swirly pattern, over a stainless steel form covered in fibre blanket.  I expected to see a nice draped vase in the morning but sadly, it just folded in half and most of it did not even bend, let alone drape.  It looks like a huge glass taco!  It was a 10" circle...a sturdy one, not sure if the glassline made the glass slightly thicker?  I thought all glass when fully fused, fused to 6mm...but it did feel kinda fatter.

Does this lack of draping mean my firing schedule was not hot enough to melt the glass properly?

I know all kilns are different so won't bother you with temperatures.....but in principle, should I "flatten" the glass again by doing another full fuse, without the form, and then try re-draping it, but hotter? 
I am nervous that the two sides which HAVE dipped, and are almost touching the kiln shelf, will just stretch more if I simply refire hotter, leaving it on the form as it is.  I think my top temperature was no more than about 620 - I found the schedule on an internet website .
thanks in advance.

What do you think?

Title: Re: draping query
Post by: flame n fuse on April 02, 2015, 10:28:33 AM
Hi Jackie
I've never done any draping, but I wonder whether the glass before draping was quite close to the heat source and whether the axis of the drape is orientated parallel to heating elements. (what I'm thinking is that if one part of the glass got soft first because it was a bit hotter, then it might drape first, pulling all the glass further away from the heat source.
Not sure whether flattening would work, but could you put it back in again over the form, but orient it a quarter turn in the kiln relative to where it was  in the first slump? I don't think I'd do it hotter.

Hopefully someone else more knowledgeable will comment!!

Title: Re: draping query
Post by: jackiesimmonds on April 02, 2015, 11:09:57 AM
I have a Hobbyfuser, so yes, you are right, the glass was probably about 1.5-2" from the elements and yes, the sides that melted are parallel with the elements.

I will try turning it, thanks for the advice.

I know you said don't do it hotter, but actually, when I have looked at what people say about draping, mostly they use slumping schedules...which are hotter than I have used. never know till you try. 

Hopefully someone else might chime in, someone who has done some draping.

Title: Re: draping query
Post by: flame n fuse on April 02, 2015, 11:25:36 AM
actually, the temp you used is pretty much what we use to slump - we tend to find that published programmes are a bit hot for us (and we have a hobby fuser too)

Title: Re: draping query
Post by: jackiesimmonds on April 03, 2015, 01:11:19 PM
I have used hotter for will try it again and see if I get better results.  I did read a US website, the girl did loads of handerkchief vases, and she said it is all about getting the temperature  right.  She did a class with a tutor and this was her schedule:

65 - 148 - hold 15
148 - 593  hold 20
65 - 648  hold 1
204 - 510  hold 60
65 - 426 - 10 min

This was so different to anything in my Hobbyfuser manual, I was very nervous to try it. 

This is what it said on her blog:
The key to the final shape all comes down to temperature.   I have conducted a experiment creating vases that have been taken to different slump temperatures.  Remember, glass most soften and begin to melt.  The amount the glass ‘melts’ is temperature dependent.  The glass will first seem to fold along one axis creating what is affectionately known as a ‘taco’ (or is it because this always seems to occur at lunch time during classes?).  As the temperature is increased, the glass moves more and additional folds are created.  At higher temps, the glass really begins to take on the form of mold it is draping over.  Go much further and you are risking it all.

‘Don’t forget time!’ you may say but that seems almost secondary to the ultimate heat the glass is exposed to.  At low temperatures, even if I hold for an extended period of time, I can’t seem to move much beyond the taco shape.

Given that I have a taco-shaped piece of glass, clearly my programme was not hot enough, I only got to the very first stage of melting the glass.  I suspect draping is rather different to slumping.

Title: Re: draping query
Post by: flame n fuse on April 03, 2015, 01:34:37 PM
let us know how you get on!

Title: Re: draping query
Post by: jackiesimmonds on April 04, 2015, 04:05:57 AM
will do!