Another slumping question.....

Bluebell · October 19, 2011, 10:46:00 AM

Hi

I'd like to make some of those little handkerchief candle holders - the ones where you put a square of glass on top of the mould. I've read Dennis Brady's notes on how to do this, but I have some questions.

1. A long time ago I got some kiln posts that I can stack for the desired height and fibre paper and was thinking this would be ok to do the job. Do I just overhang the kiln posts (say a 1/4 inch all round) with a piece of fibre paper or should it be cut to the same shape as the glass?

2. Working with a Hotstart automatic kiln - should I set the slump program to Fast, Med or Slow.

3. Dennis advises to coldwork the edges of the glass before putting in the kiln. I don't have the equipment to do that, but I don't want the glass to be too thick either. Can I full fuse 2 x 2mm sheets to get that finished edge - do you think that would work ( i.e. not 6mm)? or can I simply put a sheet of 3mm in the kiln to soften the edges and then slump it?

Any advice, as usual, is much appreciated!

Thanks x

♥♥Tan♥♥ · October 19, 2011, 02:24:58 PM

I can't help you at all with this I'm afraid but a thought has struck me. Because you are so new to fusing and learning all the time would you mind posting your working processes and results so other newbies can learn from you? I'm sure someone will be along to help you soon and if you find the time I would love to read your write up on how you got on?

Zeldazog · October 19, 2011, 04:43:11 PM

Quote1. A long time ago I got some kiln posts that I can stack for the desired height and fibre paper and was thinking this would be ok to do the job. Do I just overhang the kiln posts (say a 1/4 inch all round) with a piece of fibre paper or should it be cut to the same shape as the glass?

I've never done this, so this isn't a definitive answer, but I would probably make sure that the circle of fibre paper is just a bit bigger than the kiln posts - make sure you're slumping onto a shelf or similar thuogh, so that if anything goes wrong, the piece over fires and the glass drops off/drapes too far, you don't get glass stuck to the bottom of your kiln.

Quote2. Working with a Hotstart automatic kiln - should I set the slump program to Fast, Med or Slow.

As far as I know, the only part of the programme that is affects will be the initial heat up speed - so, the answer to this question depends on a lot of factors - how big is the piece, how thick is the piece, has it already been fired before.

Quote3. Dennis advises to coldwork the edges of the glass before putting in the kiln. I don't have the equipment to do that, but I don't want the glass to be too thick either. Can I full fuse 2 x 2mm sheets to get that finished edge - do you think that would work ( i.e. not 6mm)? or can I simply put a sheet of 3mm in the kiln to soften the edges and then slump it?

Two things - cold working doesn't necessarily involve lots of big equipment, such as flat laps or linishers. Why not get a couple Diapads (hand lap pads) which all you need is a bit of elbow grease and a water to take off those sharp bits and soften off the edges.

As for whether you fuse two 2mm sheets together, or soften the edges of a 3mm piece, yes you can do either, but you're adding a process - remember that for subsequent firing and annealing schedules. And of course, only you can determine with some testing as to what your ideal firing programme is going to be.

Lucas · October 19, 2011, 04:48:16 PM

Hi! Not sure how much help I can be, but have a few pointers to start with!

1 - stacking the kiln posts should be fine to give you the height you want, but I think the quickfire paper will need to be bigger than to just cover the top of the posts - as the glass warms and the four corners 'flop' down (very technical phrase that) if they touched the posts lower down the glass could still stick there. Are you going to do this all on top of a shelf? If so you should probably either use thinfire paper on the shelf too, or else use a shelf primer, just in case the glass droops that far (see, there's another one of those technical terms!)

2 - The kiln - is that the round(ish) one? I have one with the same programmer (a firebox 14) but have had to use all my own programmes. Mine (not necessarily the same with yours!) had presettings but all for system 96 glass, and I use bullseye. Which glass do you tend to use?

3 - I think if you full fused 2 2mm pieces the edges would draw in and make your shape a little ragged round the edges, and the glass will be pulling in to try and get to the 6mm. I personally wouldn't worry too much about coldworking the edges - it really won't make much difference to the overall effect. Why don't you give it a go with a single 3mm piece and see how it turns out? (and post some pics for us to see too!)

Tan - that sounds good - go for it Bluebell!

Lucas

Lucas · October 19, 2011, 04:49:18 PM

Cross posted!

♥♥Tan♥♥ · October 19, 2011, 05:44:27 PM

Brilliant info both of you though I am squirreling all of this fusing info away in my mind so thankyou to both of you for taking the time to post on this.

Zeldazog · October 19, 2011, 05:56:12 PM

Quote from: Lucas on October 19, 2011, 04:48:16 PM
1 - stacking the kiln posts should be fine to give you the height you want, but I think the quickfire paper will need to be bigger than to just cover the top of the posts - as the glass warms and the four corners 'flop' down (very technical phrase that) if they touched the posts lower down the glass could still stick there. Are you going to do this all on top of a shelf? If so you should probably either use thinfire paper on the shelf too, or else use a shelf primer, just in case the glass droops that far (see, there's another one of those technical terms!)
Lucas

When you said Fibre paper, I assumed you meant the thicker ceramic fibre paper, which, so long it's a bit bigger than the post, there's no way that the draped glass would touch the post as that would involve it going inwards - beyond the forces of gravity! I wouldn't recommend thin fire (on top of the posts) as it would just disintegrate under the weight of the glass.

Lucas · October 19, 2011, 05:57:31 PM

Good god there's some handy folk about!

Bluebell · October 19, 2011, 07:24:15 PM

Hi

Thanks everyone! Great advice as usual.

Yes, the thick fibre paper is what I have in mind. Also, I'm very wary about anything going where it shouldn't go and for that reason, I've got a kiln shelf which is primed regularly. Also I put thin fire below if there's a potential risk.

I only use Bullseye 90COE. I have used some Spectrum 96 but only because it came in the free pack with the kiln. Once it's done I probably won't be using it again as the majority of my glass is 90.

This is soooooo exciting. Thanks guys - I guess I just needed a second opinion. I'll keep you up to date.

I took some small slumped dishes out of the kiln this morning (another first for me) and I'm really pleased with them.

BTW....changing the subject......I read a really good tip (can't remember where now), about minimising bubbles on large pieces (perhaps a large plate). The tip was, in preparing a full fuse, to cut the base glass into strips, lay them together again and place the top glass over them. Apparently any trapped air will find an easier escape route though the cuts, thereby reducing the amount of bubbles on the surface. Haven't tried it yet - but I will!

Let you know how I get on with the candle holders.

Thanks again! x

Lucas · October 19, 2011, 07:53:40 PM

Just wanted to remind you that the preset programmes for the kiln are probably the presets for system 96 glass - there are some differences in the temps etc that you would use for system 96 and bullseye. I programmed mine with schedules that I found around and about (and the bullseye info on their site is excellent) and it honestly wasn't anywhere near as difficult as I thought it would be!
Good luck, and let us know how it goes.

L

Bluebell · October 19, 2011, 08:29:52 PM

Hi Lucas

I've been told this before (about the presetting) and it's really frustrating. You see I'm really not good with techy stuff. I'd really like to come away from the automatic program because I'm just not learning how the glass reacts at all with time n' temperature.

I'd love to have it programmed to Centigrade, doing my own firing schedules and really getting to know my kiln.

When I bought it, I thought that was the quickest route to production and it has been to a certain extent, but it's really hindered my learning. I know it can be changed to "normal" but I'm a bit nervous of pushing the wrong buttons at such a crucial time in the crafting season.

I promise I'll look into it and I'll check out the info at Bullseye - thanks a lot!

Zeldazog · October 19, 2011, 08:36:13 PM

Push it! Push that button!!

If it comes to it, and you feel like you've gone too far, and feel bewildered, there's a factory reset option to take it back to full glass fire mode anyway.

You are totally right, you will learn far more from programming it yourself - I am sure its not the first time you will have heard me say about each kiln being different and you need to get to know your own, etc, and that's the best way to do it.

flame n fuse · October 19, 2011, 10:18:17 PM

re fibre paper etc - perhaps you could just coat the posts and shelf in kiln wash instead? - the soft glass might pick up bits of the fibre paper while it's softening. You'd probably get away with 2 x 2mm sheets and if you fused them together before slumping, you'd get the softened edge.
Another way to minimise air bubbles on big pieces is to lay a few transparent stringers from the middle to the edge - they help to let the air out and are invisible when the piece is completed. (Or I suppose you could use stringers which matched your base colour). I would be wary about cutting a lot of strips and laying them side by side, because you can often see the join after the piece is finished.

The Bullseye forum is a useful place to ask questions about fusing and slumping.

Lucas · October 20, 2011, 01:47:41 PM

Where did you get the kiln from? I only ask because I got mine from Warm Glass (www.warm-glass.co.uk) and was told to give them a ring if I needed any help. they've been lovely when I've visited as well, so I'm sure they would be able to help. Do you have the instruction manual for the kiln? If you think it would help you're welcome to pm me with your phone number and I can try and take you through the straightforward one time deal things - changing to degrees c for example.
(Warm glass would definately be more helpful though, I just know sometimes things like that can be a bit intimidating)

Bluebell · October 20, 2011, 07:34:51 PM

Hi,
I got the kiln from Warm Glass. I agree with you - they've always responded to any of my questions and have been very helpful. I do have a manual and it's just a case of studying it.

Thank you so much for your kind offer of help.

I'll have a go at trying to figure it out before too long and if I get to the point of tearing my hair out, I'll get in touch.

Thanks again! x