A student emailed me this morning asking if there were any books on the chemistry of glass - colours reactions and so on. Since I emailed back rather a long reply I thought I may as well share it here. I'm not claiming it to be super accurate but it does try to answer the basic questions like "what is reduction" and so on and there's a few good links which might be useful to someone:
Colouration:
All glass is pretty much the same basic "stuff" but you can get the different colours by adding different oxides. These are usually metal
This link has a good table of colours:
http://geology.com/articles/color-in-glass.shtml
You get reactions because some of these oxides will react when they are mixed together. So, a typical reaction is that between turquoise glass and ivory/yellow/some reds.
I've always understood this to be a selenium/copper reaction. So while some colours will sit happily on top of each other without a reaction, others will form a dark line where the two colours meet.
I think Corina Tettinger had a good book out on colour reactions:
http://www.amazon.com/SPOTLIGHT-BEADS-VOL-REACTIONS-Lampworking/dp/B003K2GM16
The other two processes you need to be aware of in beadmaking is REDUCTION and STRIKING.
You can now buy lots of reducing or striking glass rods. People tend to clump them together but the two process are very different.
Reduction happens when the glass is heated in an oxygen starved flame. So you can either turn your oxygen down on a dual gas torch or you can work at the bottom of the flame or even cover the air holes over with foil on a hothead to get reduction.
When this happens the oxides in the glass tend to be stripped of their oxygen which results in a colour change to the glass. If there is a lot of metal to begin with you can get a metallic lustre forming on the surface of the glass. Double Helix "Triton" is a good example of this. As you can see from here, there are lots of others:
http://www.doublehelixglassworks.com/reductioncolors.aspx
If you add oxygen back to the gas mix you will usually (not always!) reverse this process and the lustre will vanish.
So, it's a good idea to reduce glass right at the end of the bead process, after you've finished all the shaping and decorative bits which require a neutral flame.
Reduction is essentially a CHEMICAL process.
Striking is a thermal process. Some glasses are strikers. That is, they start of as one colour and then change permanently to another colour. Usually, transparent reds are strikers. They start our as a straw yellow colour and then change to a deep red. Some of the fancier "designer" glasses also do this - like Double Helix again:
http://www.doublehelixglassworks.com/strikingcolors.aspx
Striking is essentially a thermal process as it involves getting pigment crystal to form - they only do this at a specific temperature. Usually this is lower than the melting temperature. So in effect - you make your bead, let it cool down for a few seconds and then reintroduce it to the top of the flame where the heat is lower. This usually causes the glass to "strike". Sometimes putting the glass into a hot kiln will actually do the same thing and beads will often strike - or change colour in the kiln. BUT, as with reduction - striking can be reversed so if you heat the bead up again quite fiercely the colour pigment will "redissolve" back into the glass and it will become the same colour it started out as.
More on striking here: http://en.wikipedia.org/wiki/Glass_coloring_and_color_marking
Hope that answers a few of the usual questions! :D
Thanks, there are some good links there :)
I find glass chemistry really fascinating. I think it may also play a greater part in boro reactions, which is another reason for my interest (obsession...). The Glass Alchemy guide to boro colour contains a lot of interesting information on boro striking and boro chemistry generally - http://glassalchemy.com/index.php/resources/user-manual (http://glassalchemy.com/index.php/resources/user-manual)
...and the Corning Museum of Glass has quite a bit of glass chemistry information (http://www.cmog.org/dynamic.aspx?id=264#science_technology (http://www.cmog.org/dynamic.aspx?id=264#science_technology)) as well as an interative kids version of glass chemistry on the Corning site ("heellllooooo there, glassmakers!!" - http://www.cmog.org/glasschemistry/ (http://www.cmog.org/glasschemistry/) )
Excellent info here, thanks.
Society of Glass Technology is aimed at furnace work but their site is worth a visit I feel
http://www.societyofglasstechnology.org.uk/cgi-bin/open.cgi?page=index&sessionid=36754110
Ian
thanks Sal, that was a really interesting :)
Sal, please feel free to add this to the Wiki...
Um, how'd I do dat? ???
Will you do it for me.......? Blinks innocently....... ;D ;D
Sal
thanks - really interesting post :)
'Coloured Glasses' by W A Weyl
Sean
Oh for goodness sake!! Talk about not being able to escape your past.... ::)
I went to search for that Weyl book on Amazon and actually found myself thinking this one on the Science and Archaeology of Materials looked really interesting... http://www.amazon.co.uk/Science-Archaeology-Materials-Julian-Henderson/dp/0415199344/ref=sr_1_15?ie=UTF8&s=books&qid=1276271641&sr=1-15 (http://www.amazon.co.uk/Science-Archaeology-Materials-Julian-Henderson/dp/0415199344/ref=sr_1_15?ie=UTF8&s=books&qid=1276271641&sr=1-15)
as does this one http://www.amazon.co.uk/Archaeological-Chemistry-Paperbacks-Mark-Pollard/dp/0854042628/ref=sr_1_16?ie=UTF8&s=books&qid=1276271641&sr=1-16 (http://www.amazon.co.uk/Archaeological-Chemistry-Paperbacks-Mark-Pollard/dp/0854042628/ref=sr_1_16?ie=UTF8&s=books&qid=1276271641&sr=1-16) on Archaeological chemistry.
Aaaaagh, metallurgy!!!!
One of the things I love about Lampworking - it's got that 'Alchemy' feel to it ;D
This is really fascinating stuff Sal, thanks for this!
Hazel xx
Good stuff, I like a bit of geeckery. lol
That's great info! This is the first time anyone managed to explain striking to me. So far everyone I've asked have just said "oh, I don't know, some chemical process I guess". I like understanding why things happen, not only learning that they do.
Wow Sal......you ever thought of writing a proper book?
This is just the type of info I have been looking for in countless books. I do love to know the nitty gritty of what I am doing and why I am doing it.
This forum is just great for this type of stuff ;D
Wow, this is great Sal, thanks!
Quote from: Terri on June 14, 2010, 10:50:32 AM
Wow Sal......you ever thought of writing a proper book?
Yeah - but Joan beat me to it! LOL Only kidding ;) . Well, I started writing a book a few years ago but it got to over 200 pages. I dont' write very concisely so I have to force myself to rein in a little. Then I made some DVDs and then loads of people came out with various e-tuts and so on so the book project got a bit shelved. Would like to revisit it sometime but never quite found the time......
Glad it's helped a few people.
Thanks!!! ;D
Geektastic and fascinating stuff there - thanks :-D
Quote from: Redhotsal on June 14, 2010, 11:31:18 AM
Quote from: Terri on June 14, 2010, 10:50:32 AM
Wow Sal......you ever thought of writing a proper book?
Yeah - but Joan beat me to it! LOL Only kidding ;) . Well, I started writing a book a few years ago but it got to over 200 pages. I dont' write very concisely so I have to force myself to rein in a little. Then I made some DVDs and then loads of people came out with various e-tuts and so on so the book project got a bit shelved. Would like to revisit it sometime but never quite found the time......
Glad it's helped a few people.
SAL:
I refuse to buy e-tutes but I'm a book-a-holic, and you know I've wanted you to do a book for years! ;D And I want one of the first signed copies please ;) There is nothing like flicking through a beautiful book with lots of drooly pics and text that makes you smile, while sipping a cuppa with your feet up. My idea of heaven! If my house burned down, books would be what I missed most.
I also think it would be worth you jotting down your trials and tribulations you've gone through in the process of setting up the shop, it would make a fab book or series in a mag! You have a clear way of writing, you simplify things without dumbing down, and yet you inject humour too. A geeky glass book, somewhere between idiots guide and scientific text book would be fab!
Quote from: beadysam on June 17, 2010, 10:45:29 PM
I also think it would be worth you jotting down your trials and tribulations you've gone through in the process of setting up the shop, it would make a fab book or series in a mag!
Heh - Carvers "How Not To....." Series..! ;)
That was an interesting post, thank you, one of those 'oh yeah' moments, when things just click into place! ;D
Really interesting stuff here...thankyou :)
wow! thank you Sal! I'm six weeks in to my Journey of Glass, got a mass of glass and I am only just figuring out all of it's potential. Thank you very much. I shall go play now ;D x
I'm a newbie too (this is my first post!) - and you made it all so easy to understand, so thanks! Now all I have to do is put it correctly into practice ...!
Thanks Sal - very informative post!
Great post ;D ;D ;D
and I thougth I was just going to play with glass and make a few beads and see what i got. Now i have to study alchemy, anyone got an alembic? ;D
But seriously folks, great thread with lots of info in easily understood text, no mean feat given the subject matter, well done Sal and others. it helps me to understand what it going on and why when I apply lots of heat to coloured glass !
There is an article on flame/surface interactions and art glass in Microscopy Today from Sept 1020. Got to the URL below, open the Archive and look for issue volume 18, issue 05. There is a similar article in The Glass Bead from this past winter.
http://www.microscopy-today.com/index.jsf
Robert
I think this was mentioned at the time - the article looks very familiar :)
Well, I guess it's good to know that the article made it this far and didn't sink like a stone. :) I'm working on another involving mists generated from cold working processes.
Robert
QuoteI'm working on another involving mists generated from cold working processes
Sounds like a November morning in the Lakes. ;D ;D
But also very interesting :)
A November morning in the Lakes is more fun.
R
;D ;D ;D
I have been thinking that what we need (not looking at you necessarily Sal :) ) is an encyclopedia of glass, listing all the glass available, what it does, how to work it, what colours go with what, reactions, etc etc etc. As you say there are bits and bobs in tuts and in various books, for example I noted a comment in Nellie Rees's book which I got for Christmas on a yellow that isn't swallowed by petrol green. Would LURVE something like this, even though I know it would be VERY expensive and VERY big. xxxxx :)
Such a database would be much more effective if held in a digital format - There would be too much information to handle any other way, and it would need constant revision as manufacturers produced new colours.
Maybe the sort of thing that users would subscribe to as an online service.......
Sue
Anyone ever tried to work out the possible permutations? I guess it must run to millions. Especially if you include frit and other embellishments?
Sal - I'd be happy to have a go at some editing if you want to revive the book at some point. I am pretty good at succinct!
Kazx
Quote from: Kaz on December 28, 2011, 09:02:12 AM
Anyone ever tried to work out the possible permutations? I guess it must run to millions. Especially if you include frit and other embellishments?
Sal - I'd be happy to have a go at some editing if you want to revive the book at some point. I am pretty good at succinct!
Kazx
It would be HUGE. Perhaps there could be a main volumn with the 'normal' glasses in it then separate volumns for silver glass, frit, etc etc, just really thinking outloud as this might not work? A database would be easier, and as you say could be kept up to date, but a book would be soooo beautiful, you can't stroke a database! ::) ;D. I would be very willing to help anyone do this, but in terms of knowledge etc I am still very much a newbie. I do like proof reading though! ;) :)
I know boro frit tends to react a bit differently to the glass in a rod, but generally that's just because it is in a thinner layer, so less concentrated... perhaps this also applies to silver-rich soft glasses, but wouldn't most other soft glass frits just react much like the glass itself?
At the back of my mind, I have the idea that a database along these lines already exists somewhere.. but it could just be my mind being fuzzy. It could also be difficult to produce given that glass colour chemistry still isn't always that exact and can vary from batch to batch, depending not only on what chemicals are put into the mix but (apparently) what atmospheric conditions are like at the time.
I would have to say that I've also found, since starting to use boro, that part of the fun for me comes of not knowing exactly what will happen at any point. It is nice to have a few rules of thumb, for example that most reds will turn an amber purple to stringy yellow, or greens next to ivory will react to form a line, but also nice when something unexpected happens :)
This is a great thread :)
Hi Sally thanks for posting this, I was looking for answers.
I've got about 103 2 foot X ¼" rods (24 colours and a couple of clear) I bought them 15 years ago and it's only recently that I've dug them out to play with. I originally wanted them to make a screen with them held side by side in a frame but never got around to it.
The rods were from Polwden and Thomson, I phoned them up and they had my name on record but not what I'd purchased, they were able to help me as I still had the labels on the glass giving the colours and from that they told me I have COE 100 glass and that's fine.
But I have a few questions.
1) I understand that the higher the COE the softer the glass (lower melting temperature) so if that's correct how would you quantify the difference?
2) I'm using a Hot-Head with propane and 4 Bar regulator, it aint fast!
Would I find COE 104 and softer?
3) I think what I'm going to ask now is to do with 'Striking.'
I've only made a hand full of beads and I noticed that the Ruby Red transhumant rod was completely opaque when I'd finished, I thought I'd burnt it. I made another keeping it further away from the torch and that was semi opaque. The next bead that I kept well into the sweet spot is, millimetre for millimetre, has about the same depth of translucency.
So is the 'Striking' or was I zapping it?
4) I pulled a stringer from the Polwden and Thomson 'Diopal White' COE 100 rod I have and this drew down to clear, I thought it was just a density issue but when I applied heat to the stringer it assumed the same solid white even though it's only 0.8 mm Ø
So this again I guess is 'striking,' if that's correct what tests or conditions can I apply to get a feel for how to control this effect?
Only 4 questions but I know it all takes time to answer, but hey I figure you guys have all the answers.
Kind Regards ... Andy
This isn't going to be anything like a complete answer, but:
If you are thinking of using the P&T rods for flameworking, then I assume that what you are really asking is will they work ok in a Hothead flame? I think the answer to that is yes, they will melt but from memory, P&T glass is quite concentrated and so may well be more viscous and stiff to work with than other glass. COE isn't the only factor to consider, the concentration and the particular glass chemistry also play a part. So, while they'll melt, they may well not work particularly easily. They may also have a few problems with the reducing flame atmosphere.
104COE glass, I imagine, will be easier than the P&T to work with a Hothead. I used a Hothead for about a year and used both Effetre and the 90COE Bullseye to make beads.
I would guess that the ruby is opaque because you are overworking it (spending too long working the glass) and the chemicals inside are 'livering'. It's a while since I've used soft glass of any sort and I can't quite remember if this is also flame atmosphere-related. Striking is when a colour 'develops' - you can get red glass in a clear rod form that 'strikes' to red either in the kiln or the flame. That sounds like what you're seeing with the white.
One last thing - glass is occasionally a law unto itself and can only be controlled so far. If you are wanting it to conform to tests and perform identically, time after time, I strongly suggest that you never, ever go near borosilicate coloured glass. It'd drive you mad!! ;D ;D
Hi Andy,
Okay then......I'll attempt to answer your questions:
COE actually means Coefficient Of Expansion, i.e. how much the glass expands in size as a function of temperature. Although for lampworking glasses such as Effetre or Plowdens the actual measurement of COE is (I think) 10 to power -7 metre/C - something like, that but we usually abbreviate it to an empirical number - like 104 for Effetre, or 100 for Plowden. Bullseye is 90, Spectrum is 96 and Borosilicate is 33. So, in essence, the higher the number the "softer" the glass - so it will be less viscous and easier to melt, the higher the number. It's actually quite hard to quantify this because you will notice differences even within the same range: for example - transparents tend to be stiffer (higher melting point) than opaques, even though they have the same COE, so although viscosity is related it isn't a straightforward function of COE.
In practical terms - while Effetre would be the glass of choice for a hothead you can still use Plowdens even though it's a little stiffer - in fact it's a glass that many of the "old school" bead makers started off on. Sadly - Plowdens was taken over last year by an American company and I believe that they are no longer producing rods for lampworking.
However, you cannot mix glasses of varying COEs together as they will crack as they cool. The general rule of thumb is not to mix glasses that are over 2 points of COE apart. Having said that even within a "group" of glasses that are all meant to be the same COE you will get a variation - it's a "range" rather than an actual absolute figure. So, as an example, I've never managed to encase an "alabaster" type of pink with a clear encasing even though the two glasses are meant to be compatible. This is something you can only find out with experience.
An exception to this is when you are using "frit" or powdered glass. Commercial frits tend to be 96COE yet we can still use them with 104COE. this is because the frits tend to be surface elements - and as long as you stick to the 10% rule - don't use more than 10% (by weight) of frit or enamel on a bead where the COEs don't match.
For most bead makers the usual glass of choice is 104. This is because - as you suspect - it is slightly easier to melt than Plowdens - but perhaps more salient is that there is a bigger choice of glass in the 104 range. You can use Effetre, you can use CIM (Messy Color), Reichenbach, Lauscha, Double Helix.....in fact, many manufacturers have engineered their glass to this range for bead makers and soft glass users. By and large the glasses are interchangeable - though some manufacturer's glass is a lot more "stable" than the others. I use Effetre because they have been making it in the same way, in the same place, with the same recipe for literally hundreds of years. It's cheap and consistent. Lots of people are fans of CIM as there is a large range of colour, but, they have had some compatibility issues with this glass, which is not really suprising as CIM is a relatively new glass and many batches are not as "proven" as the older manufacturers. (have to be careful what I say here! ;) )
But yes, you would find 104 easier to use and there is also a much bigger choice of colours. Having said that - you may want to treasure your Plowdens as it is becoming a rare glass now.
So....striking is when you get pigment growth within the glass and this only happens at a particular temperature - often around 500C. To form your bead you need to go above 500C for the glass to actually melt, and when you do this your glass will go colourless. If you take the glass out of the heat and leave it, it will stay unstruck. If you allow the glass to cool for a few seconds and then introduce it to the point in the flame where striking occurs (at around 500C) you will get striking and the glass will take on a colour. If you go above this temperature you will start to lose the colour as the pigment is reabsorbed into the glass. So, striking is a cyclical phenomemon depending on temperature. Sometimes unstruck glass will strike in a kiln as the striking temperature is similar to the bead annealing temperature. It is however, dependent on the actual type of glass and hue. It is actually possible to overstrike some glasses and the colour will go more opaque and "liverish". Not all glasses are strikers - but usually, if you want a transparent red, orange or yellow, and some pinks (and the diopal white) you will start off with a striking glass. And it usually is supplied in "unstruck" form. Plowden were unusual as I remember some of their transparent reds are pre-struck.
So to play around with striking you need to go well over the striking temperature to get the glass to melt, but then the time allowed for the glass to cool prior to reinsertion into the flame (vs the position in the flame) will also affect the strike. As you have found - a good strike can be found at the top of your flame (as this is probably a good approximation to 500C on your particular hothead.) Hope that makes sense - I'm not sure how well I explained it? To make you feel less alone - there are many established bead makers who really can't wrap their heads around striking and it still is a mysterious and randomn process to many - so they tend to avoid the whole thing. BUT then.....if you become an expert on striking get yourself some "silver" glass - like Reichenbach Iris Orange (a.k.a. Raku/Magic/Multicolour) or some Double Helix strikers like Chaos or Terra. If you strike these correctly you can get a spectrum of colours. Kim Neely (Bluff Road Glass) is a bit of an expert on striking Double Helix glass. Check out the "Essential Terra" sets on here - all the same glass - a rather boring looking beige rod - but if you hit it with the right temperature, you will get a huge gamut of colours: http://www.bluffroadglass.com/Gallery/album/Sets/index.html
Anyway - last thing I wanted to do was get you addicted to expensive glass!!! ;) :o :o :o
Thanks to garishglobes and Redhotsal for the answers.
Thanks for the detailed response.
OK on the Coefficient Of Expansion, CoE has always been important to me in my engineering work, a number of things in your car for instance are 'Heat shrunk' together. The stator-motor on your car engages on to a large diameter gear on the flywheel to turn the crank. That large gear is made of hardened steel in the form of a thin narrow ring about 10 or 12 inches internal diameter, it's heated just enough to expand it so it can be dropped onto the large cold flywheel (made of cheaper steel,) where it immediately cools and shrinks and grabs onto the flywheel forever with incredible force... (I'm off again.)
What I was after was a relationship between CoE and melt temperature but I guess it's very difficult to be specific about when the glass is said to melt because of the wide softening range. As I'm sure you know there are still some aspects of engineering that are considered a 'Black Art'. But as a guide it looks like I can take it that glass with a higher CoE will be easier to work.
I'll buy some Effetre 104 and see how it flows as with the stuff I've got now is like trying to stir a tin of treacle that's been in the fridge, you can do it but you wouldn't want to do it all day.
If there's a big difference I'll see if I can use the 130 or so CoE100 rods that I have in another way. We've recently gone a bit 'Glass mad' I've stripped out the top row of windows in the porch and fitted coloured glass in its place and done the same thing with 5 panes over the loo door.
Again OK on 'striking' that looks like another topic/distraction all on its own.
I've got to be a bit careful as I've got a load of Bullseye CoE 90 that I'm planning with in the kiln and I'm sure I'll get some of it mixed up.
I don't know how far I'll go with bead making but it's a technical process and I like try and understand 'processes.' I've found the better you understand the process the better you can master it; I reckon that Les Dawson understood how to play the piano really quite well.
Sophie made her first two beads last night, so I'm getting worried I might lose my workshop if the bug bites.
By the way Sophie said she's not too sure about me communicating with a lady on the internet called Redhotsal.
I must get some pictures of our first feeble bead efforts posted soon.
Thanks again for the feedback, you both put a lot of effort in and I really do appreciate the time it takes.
Question... is there a 'best place' to buy Effetre rods as I'll be ordering some today.
Kind Regards ... Andy
Probably Tuffnells!
But it's a while since I've bought the soft glass....
Quote from: Andy Davies on January 10, 2014, 11:15:49 AM
Question... is there a 'best place' to buy Effetre rods as I'll be ordering some today.
Kind Regards ... Andy
Tuffnells.
Nick
Hi Andy,
Yes, I think it's probably beyond my remit to know the actual relationship between COE and melt temperature. Someone has probably plotted a graph somewhere on line - but as you rightly say - glass doesn't really have a melting point in the same way that a metal would. It's more like chocolate, really....! Also, while you will find a lot of detailed data from the manufacturers themselves (especially Bullseye - who seem to be quite prolific with information) - you probably won't find a lot of comparative data just because of the "competition" arising from different manufacturers.
But, on a practical note - higher COE will melt easier. In fact, you can go higher than 104, Satake glass which is beloved of many Japanese glass workers has a COE of 120, which makes it as soft as the proverbial. One or two people have used it on here (it's not easy to get hold of) but of these people most say it's difficult to work with precisely because it is so soft. The Japanese bead makers have a tendency to make a lot of murrine (glass cane with a pattern in it - like a stick of rock) - so for this purpose it is well suited, but for anything with "structure" - like figure work, you can forget it. Many people use borosilicate for figurework as it's so stiff. Some crazy Venetians use Effetre for figure work - but it has to be said that it's more challenging to use this for sculpture.
Remembering back - I started off with Plowdens glass on a hothead, so I know it can be done. But you do need a lot of patience - and I do remember Plowden glass as being noticeably harder to melt than Effetre. Keep the Plowdens though - because if you do decide to start making glass animals as opposed to beads it will give you the advantage. My friend Bob Martin - who makes a lot of glass animals for me, much prefers Plowdens to Effetre for figure work - though admittedly he works with propane and oxygen.
One advantage people will say that working slowly on a hothead with stiff glass is that it does teach you better glass control than working flat out on a minor burner with softer glass. By the way - don't even attempt to melt Borosilicate with the hothead - not unless you enjoy watching glaciers race past you. But, I must confess, if you are impatient you may find melting most things on a hothead as slow. It is much cheaper though than using a dual gas torch like a minor burner.
Effetre is Venetian and of course comes from Murano (technically, though the factory is in Venice) and while you can get it from them, it is usually easier to buy from Tuffnellglass - http://www.tuffnellglass.com/. They stock pretty much everything you'd need as a bead maker....try not to get too distracted.......I may have to open a book on how long it takes you to buy a dual gas torch ;)
By the way - if you are about to melt together two "unknown" glasses you can test their compatibility by melting a small dot of glass A onto a rod of glass B. At the intersection of where the two glasses meet melt and then draw out a long "hair" of glass - which will hopefully contain half A and half B. If there is a difference in COE then the glass will bend into a curve. If the COEs are the same it will remain as a straight line when broken off.
Quote from: Andy Davies on January 10, 2014, 11:15:49 AM
Sophie made her first two beads last night, so I'm getting worried I might lose my workshop if the bug bites.
You have almost certainly lost your workshop. ;)
Quote from: Andy Davies on January 10, 2014, 11:15:49 AM
By the way Sophie said she's not too sure about me communicating with a lady on the internet called Redhotsal.
If this carries on you may be losing the house, too! ;) ;) ;)
Thanks Guy's I'd like to support Tuffnells as they've been good so far with other stuff and thanks again Sally
Now I'm going to challenge the conventional wisdom. It's said that the higher the CoE number the softer the glass and I've seen that on the web, now as a general rule that might be right but in reality it can't be taken as fact.
(Remember what I said on the YouTube wind generator video, 'you can't believe everything you see on YouTube' but it can be the same on the web in general, someone says something and it becomes law, well internet law.)
I've just cut up some Clear CoE 90 Bullseye to compare it with the Clear P&T CoE100 that I have and boy the difference is phenomenal. The CoE90 flows like soft butter, a real joy to play with. With the P&T I'd been thinking that I was going to have to go onto a two gas torch to do any good. When I see how folk on YouTube play with the glass I thought it was all down to the extra heat but it's not. Before I get blasted I know adding oxygen makes a big difference (I've done a lot of oxy-acetylene welding) but unless you've tried the P&T CoE100 glass you may not know how stiff it is in comparison.
And remember I haven't any appropriate practical experience with other glasses.
I can't wait to get some soft glass as I think I'm really going to have some fun with it, it's a major step change, just like having the light switched on
regards ... Andy
Just thought I'd let you know I've gone for it and ordered 4 ¼ Kg of mixed Effetre rods, opal and clear plus some mixed stringers on next day delivery, pity we can't magic it down the internet and get it now! (Kid-in-candy-shop mode) If it softens anything like the Bullseye CoE 90 I'll be over the moon, otherwise I'll be filling in more windows in the porch with it.
I'll let you know how I get on.
Regards ... Andy
In my experience it should soften a bit quicker than the Bullseye. Not used any P&T, so can't judge.
Nick
If I'm remembering correctly, Sophie is your MIL, in which case she may have some unused offcuts of Spectrum glass. A lot of the Spectrum is COE 96 and makes good glass beads provided you don't mix COE's. The transparent waterglasses made by Spectrum look particularly good when encased over a plain white opaque bead. I still have loads of Spectrum glass from when I made stained glass windows and have used some for beads. Cut into 1/4 inch strips they can be used as ersatz rods. Oddments can be held with small pliers. Another avenue for you to explore.
As ever I've jumped in and done it and now I'm wondering... 'Do they do dichroic glass that's compatible with Effetre CoE104 ?'
If I'd have thought about it for 10 minutes longer I might just have thought it'd be a good idea to have just one flavour of glass in the workshop as I know I'll mix them up sometime but probably only when I've made the best bead ever, that'll be the one that cracks.
Anyway I'll just have to keep the 90 and 104 separated and ditch the stodgy CoE100
I always think that it's better to do something rather than nothing but I often jump too quick, but hey I'll be having fun tomorrow and if all else fails there's always eBay.
... Andy
Quote from: Pat from Canvey on January 10, 2014, 01:36:53 PM
If I'm remembering correctly, Sophie is your MIL, in which case she may have some unused offcuts of Spectrum glass. A lot of the Spectrum is COE 96 and makes good glass beads provided you don't mix COE's. The transparent waterglasses made by Spectrum look particularly good when encased over a plain white opaque bead. I still have loads of Spectrum glass from when I made stained glass windows and have used some for beads. Cut into 1/4 inch strips they can be used as ersatz rods. Oddments can be held with small pliers. Another avenue for you to explore.
Hi Pat
I'm not into text shorthand but I guess 'Mil' is teenage jargon for mother-in-law, you hip thing.
But for the Record Sophie is my beautiful partner of 22 years, as of today actually. She's my best friend in the whole world and is extremely tolerant of all my hobbies and I love her to distraction.
But it's Sophie's mom, Wendy who made to stained-glass/leaded vase you'll have seen and yes, Wendy did give me some glass that I've used as 'stained-glass' in windows. But I've got more left over. I thought given that it's not specifically for remelting that each of the different colours would/could be different CoE's but I haven't tried mixing them (pulling two together) to test compatibility. I guess they could always be used for single colour beads but that'd be a bit boring right now.
Do you have many CoE's in the work shop or do folk generally have a one CoE approach?
... Andy
I think... that the P&T glass is probably (additionally, given the age, this is likely) really formulated for the furnace. It is possibly a more concentrated colour than glass that would be used for flameworking, which makes it stiffer?
Bullseye, I believe, is formulated to 'run' quicker despite its slightly lower COE. I have however found some Bullseye colours to be difficult to work on a Hothead because of the flame atmosphere - pinks particularly are prone to greying. Bullseye rods can also be quite shocky, especially some of the opaques!
I'm sure there is a dichroic glass that is 104-compatible.
Quote from: Andy Davies on January 10, 2014, 02:08:12 PM
Do you have many CoE's in the work shop or do folk generally have a one CoE approach?
... Andy
At the moment I have COE 104 glass (Effetre, CiM and Lauscha), Reichenbach COE 94(+/-2), Gaffer COE 96 and Boro rod for punties.
I make sure I keep them all labelled and separate though.
Jane
I bought some dichroic strips from Devardi in USA that is 104coe
http://www.ebay.co.uk/itm/321175609743?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
I have diff manufacturers but all 104 coe rods (just a bit of frit that is diff coe's)
Cheers Claire x
At the moment I have COE 104 glass (Effetre, CiM and Lauscha), Reichenbach COE 94(+/-2), Gaffer COE 96 and Boro rod for punties.
I make sure I keep them all labelled and separate though.
Jane
[/quote]
Hi Jane, all understood, how to you find the difference in pliability between types of glass (or I guess to put it another way which is the quickest to melt)
Regards ... Andy
I don't notice that much difference between COE 96 and COE 104. I love the colours that Reichenbach and Gaffer produce, and as the frit I have is mostly COE 94/96 it means I don't have to worry about limiting the amount of it in a bead.
You can use COE 94/96 frit on a COE 104 bead, but you have to stick to 5% of frit on the bead's surface in case of incompatibility.
Gaffer Robin's Egg blue is one of my favourite colours. Caroline (Beadbug) sells this glass on her website - http://www.beadbug.co.uk/
Jane
You can get 104 Dichro, but it doesn't play nearly as nicely as the 90, and, to me, always looks disappointing. Mind you, I do a lot of fusing with Bullseye and dichro. I find it very difficult not to burn the 104 Dichro when making beads, but if I use the 90 Dichro with Bullseye rods it works much better.
Nick
I have all the 104 makes, plus Spectrum and Gaffer COE96, boro, bottle, and float. This bowl was made with cathedral stained glass. (http://pic20.picturetrail.com/VOL1426/5604171/11984392/408376392.jpg) and this is a float glass heart, (http://pic20.picturetrail.com/VOL1426/5604171/24134598/408116060.jpg) and bottle glass,(http://pic20.picturetrail.com/VOL1426/5604171/22750186/407219271.jpg)
I am a cheapskate and don't like to throw any glass away.
Quote from: Pat from Canvey on January 10, 2014, 05:50:42 PM
I have all the 104 makes, plus Spectrum and Gaffer COE96, boro, bottle, and float. This bowl was made with cathedral stained glass.
I am a cheapskate and don't like to throw any glass away.
OK Pat, I never throw much away, I get my inspiration from bits and pieces around me, at least that's my excuse.
... Andy
Hi there,
If you have glass that needs striking would you do it before or after if you want to encase it?
Many thanks,
Michelle
Before, I think. To strike it you have to get it really hot, then cool it quickly, and you couldn't do this if it was encased. Strike it first, then encase it without getting the struck glass too hot. Hope that helps.
Nick