Shatter proofing fused glass

Sandera · January 04, 2012, 09:26:26 AM

You can always tell when I'm on holiday as that's the only time I feel that I've got the time to experiment. It's also the time I pick your collective brains!

I've now progressed to a bigger kiln and I'm creating larger pieces. I really want to work with a carpenter so that I can inset a piece of fused glass into a table (just below the surface of the table and protected by safety glass on top). But i'm not sure whether I would be wise to also make sure that the fused glass itself is also shatterproof. I'm waiting to hear back from my local glaziers to see if they can laminate the fused glass but I've also heard (read) somewhere about varnishing fused glass.

I suppose my questions are: has anyone on the forum done anything similar and if you did, how did you make sure that it was as safe as it could be? And can anyone shed light on the varnishing theory?

Thanks

Sandera

MeadMoon · January 04, 2012, 09:37:57 AM

Interesting. I have a fused glass table made by Colin & Lisa Badger of Hawkhill Forge and the fused glass surface is not protected in any way as far as I can tell. It's still in one piece after 2.5 years

but I am a bit careful about putting things on the glass even though they said that it was quite tough.

Sandera · January 04, 2012, 09:47:44 AM

That is interesting. Is it a very thick piece of glass?

Glyn Burton · January 04, 2012, 05:10:30 PM

How big a piece of glass were you thinking of?

I would always put the fused glass under toughend glass.If your glass was to break you could hurt someone very badly and anyway if you are selling work it must conform to the H&S standards for the furniture industry. You can laminate the glass yourself, I did it for some door panels. There is a good little book on glass lamination which I used to have, I lent it out and it never came back but you can buy it on Amazon for about £10-12. Or even try inter library loans. If you have problems tracking it down let me know and I will look in my records.

As for varnishing its a nice idea but I can't see how it would work, the varnish would not be strong enough to hold the glass together if it breaks there is a sticky film which can be used between sheets of glass but that only works if the glass is very flat which your kiln formed piece may not be.

Sandera · January 04, 2012, 05:26:33 PM

Thanks Glyn.

The piece is about 40cm x 40cm (5cm thick). The thickness is the reason I'm worried but I absolutely agree with you about the H & S issues.

I'll have a look on Amazon re the book (I'm a librarian by trade so I don't need much of an excuse to buy a book

).

Did you find the laminating process easy?

Sandera

MeadMoon · January 04, 2012, 05:33:44 PM

Not sure how thick the glass in my table is, it's difficult to tell with the metal and iron surround, but it doesn't look/feel particularly thick and definitely less than a centimetre. The middle section of glass is 60cm x 30cm.

Redhotsal · January 04, 2012, 06:00:09 PM

If you are using the panel for windows etc. I think you do have to ensure that it is "toughened". You'd need to talk to someone about the latest building regulations as I'm not exactly sure what the requirements are.

"Toughened" glass is actually annealed in such a way that if it suffers an impact it will shatter into thousands of very small pieces, just like a piece of hot glass that is cooled quickly does. So, to my way of thinking it's actually the opposite of annealed, which will shatter into large lethal jaggy shapes. It's a lot more complicated than that but if you look at a piece of toughened glass with a polariser it seems to have a very regular lattice of "stress" lines running through it. It may be possible to toughen a fused panel in the same way, but I don't know how you'd go about it??

It's a tricky one. I don't really have an answer to this - but I will just say that we used to have a coffee table which was basically a low, large wooden frame with a big piece of frosted glass (just normal - not toughened) that we installed ourselves. Once, when Emily was a toddler she accidentally knocked over a bottle of wine which was on the table. It toppled and smashed the glass into foot long lethal shards. It was a miracle no one got hurt. We got rid of the table immediately.

Hamilton Taylor · January 04, 2012, 06:09:01 PM

sheet glass is toughened by cooling quickly using a matrix of cold air jets - hence the lattice of stress lines.
I have heard of bullseye being toughened this way, for a project in alloa, but last `i heard there were problems getting the glass properly supported in the toughening machiney-rig thing. Best thing would be to get on to a glass toughener, and ask them about it. But I should think that for the thickness you mention, lamination might be easier.

Glyn Burton · January 04, 2012, 06:16:44 PM

Hi Sandera,
I have been thinking, always a painful process but I think the regulation is BS7449 and it states that if the glass is un supported it cant be bigger than 0.02m2 unless it is toughend but its a while since I had to think about it.

The book is Lamination (a glass handbook) by George Papadopoulos

The process is straight forward but smelly as it uses a resin. The principal is that the glass is held slightly apart on a slope and resin is slowly run to the gap. When the resin is cured it sticks the glass sheets together so that if they break they won't go into the sort of shards Sal described but stay in a piece.
If you can get someone else to do it I would as its messy and smelly.

Hope this helps.
Glyn

Sandera · January 04, 2012, 06:23:47 PM

Thank you all so much for your responses. As I want to sell these items then I've got to get it right and, to be honest, if anyone was hurt due to my negligence I would be mortified.
So I'll take all your experiences and suggestion on board, do a bit more research and speak to the glaziers.
There's so much knowledge on this forum - I'm always impressed!

Moreton · January 04, 2012, 06:36:36 PM

Hi Sandera. As Glyn says it is a very messy process. If you only want a one of I believe that Pearsons in Liverpool offer the service and PVS uk in Yorkshire certainly do though the web search failed to find them. May not be trading now. I would think that ordinary glaziers won't have a clue about the process .

I have George Papadopoulos' book and if you would like a read pm me and I'll lend it to you.

Pete

Redhotsal · January 04, 2012, 06:43:15 PM

I would be very interested to see what comes out of this thread, I'd be very grateful if you could keep us informed if you manage to find anything out - I would like to make (or commission) a large fused panel for our shop (to hang on the ceiling!!!) so would be particularly interested in the safety aspects of large panels of glass vs. the public!

GaysieMay · January 04, 2012, 07:49:54 PM

Nothing to add, but marking for future. Good luck sounds exciting.

jeannette · January 04, 2012, 08:04:05 PM

Yes, very interesting - especially as there's peeps put there with these for sale

It's a lovely idea.

Glyn Burton · January 04, 2012, 09:13:07 PM

If you are hanging the piece from the ceiling Sal and it is well supported I don't think there will be a problem its not as if people will be bumping into it. I made one a few years ago with each section 900mm by 450mm and 8 panels in total. I had a steel frame made to support it and it hasn't shifted (yet). I am just starting a similar wall 2.8m by 1.8 in a similar frame but that has to be laminated of course.
Glyn