Attaching Porcelain To Glass?!

[HarryThePotter]

Hi!

 

Does anyone know whether it is possible to attach porcelain to glass? I mean, attaching a small amount of glass to porcelain is easy, but can a little bit of porcelain be attached to a piece of glass?

 

For example, can a drinking glass be covered with porcelain (lets say 0.5mm thick layer) and then fired?

 

-Harry

[Mark C.]

glass melts at one temp-glazes melt at another (usually higher) clay(porcelian) melts at higher temps than both .

You can glue them together with e-6 glue.

Mark

[HarryThePotter]

I'm quite sure one could find glass, glazing and porcelain that all melt at around the same temp...

[Callie Beller Diesel]

Not really. Ceramic and glass contain the same ingredients, but in wildly different proportions. Even borosilicate lab glass or Pyrex melts at 820 degrees C, which is about cone 014. Nothing's even bisqued at that temperature. Glass is a super cooled liquid, not a crystalline solid like glazed ceramic. Yo've heard enough discussion about glaze fit being problematic because you're trying to match the thermal expansion of two substances (clay and glaze) that are more chemically and structurally similar to each other than either is to glass. Glass tends to shrink much more, and if it surrounds any impurity it tends to crack around it. Glass is sometimes formed in a kiln, but that's about where the similarities end. The firing cycles are very different from clay work, and involve a lot of slow controlled cooling and heating. Firing cycles used to create beneficial qualities in clay and glazes will create major flaws in glass.

 

It would be theoretically possible to do enough testing to figure out the expansion rate of a glass and match it to an already finished ceramic piece. It will be a lot of testing. But Mark is correct. Glue is going to be much less problematic.

[Mark C.]

Its therorectly possible but you will at the very least need a ceramic engineer to get it right.

I just thought that may be out of your budget hence the E-6 glue.

Mark

[PeterH]

I'm sorry that the first round of replies has been negative (for want of a better word, no criticism

of the posters intended).
 

Perhaps you would get a more constructive answer if you explained what effect you are trying to

achieve, rather than saying how you intend to achieve it (as it's unclear if that process is viable).

 

There may be a more promising route to meeting your goals. At guess these goals might include:

- easy manufacturing process

- nice shapes (maybe think of slip-casting from a mould taken from a glass)

- nice colours (many/most glass colours can be achieved in DIY glazes)

- ultra-thin porcelain walls (... interesting topic)

- very thick inner glassy coating

- ????

... please tell us what you are looking for

 

PS Now for my own doubts.

 

I'm quite sure one could find glass, glazing and porcelain that all melt at around the same temp...

 

If this was possible, IMHO it's unlikely that you could find commercial drinking glasses made of that glass.

 

Even if you could, you would still have to worry about: cracking due to differential shrinkage during drying and

firing; crazing and spalling due to differential shrinkage when cooling; glass flowing during the firing (glazes are

usually more viscous to avoid this); ...

 

Personally -- and it may be lack of imagination -- I cannot see how to get past step one (apply porcelain slip to

glass and let it dry) without it cracking. Or have I misunderstood your proposal? 

 

[Not entirely true if you use ceramic tape technology I suppose. But then surely it would crack during the first

stages of firing (as the porcelain starts to shrink before the glass melts).]

 

[HarryThePotter]

Thank you all for your answers, I appreciate them. I can tell years of experience are behind them.

 

I have ditched the covering idea as much too hard.

 

 

The original problem is this: I want to let light through the wall. 

 

I have used Mont Blanc porcelain, but it does not seem to be transparent enough. Do you know of better mixes?

 

Another option would be to make a hole in the side of the mug, and place a piece of glass on top of the hole or inside the hole.

 

What are your opinions?

[neilestrick]

A good grolleg porcelain will be translucent if thin enough.

[Callie Beller Diesel]

Where are you? Geography will dictate specific suggestions.

[HarryThePotter]

I'm in Scandinavia

[rikahawes]

To glue glass to ceramic, and have it hold up over time and without significant discolouration, use Hxtal. It's a 2-part epoxy that is conservation / museum quality. I believe the longest tests with Hxtal have been about 25 years. I've repaired a LOT of studio glass and ceramics that were assembled with adhesives and most fall apart after a year (most retail epoxies) or a decade or two (silicones and better quality epoxies).

It's close to optically clear and if you are interested, the data on that is available via conservators websites/forums, etc.

Available from HIS Glassworks in the USA and Conservation Supply.

[Chris Campbell]

I am trying to understand ... You want to see into the glass or do you just want light to show through?

Translucence is clay ... Seeing through the walls means glass ... Combining both could mean leaks.

[rayaldridge]

It should be possible, since glass can be formulated to soften at very high temperatures-- so within the range of high-fire porcelain.  The big issue would be dissimilar contraction rates while cooling.  Glass in general must be annealed to survive cooling without internal strains that could make the glass shatter, and matching the two substances in that regard would be a technologically very difficult task.

 

As you said, attaching glass to porcelain in small areas is easy.

 

 

[Tim T]

If you just want it translucent, and not transparent, then I'd suggest bone china is the way to go as it is more translucent than porcelain, though you need to use moulds and slip casting.

To see what can be achieved, have a look at Sasha Wardell's work (http://www.sashawardell.com/).

If you want it transparent, I'd suggest bonding the glass and ceramic together with a clear epoxy adhesive.

[douglas]

From the first post, it sounds like you want drinking glasses that will let light shine through the walls. Your original idea was to buy glasses you like, and add clay to reduce the transparency, making it a light opaque wall.

 

Unless you are an accomplished potter who can build thin walled porcelain vessels, I would recommend you use your first idea, but finish the glasses using a different medium than caly. Two things you could try:

 

Food safe enamel paint applied to the outside of the glass

http://www.amazon.com/Miss-Mustard-Seed-Milk-Paint/dp/B00II294C2

 

Etching or distressing the glass exterior to break up the transmission of light, giving a frosted exterior.

http://www.amazon.com/Armour-3-Ounce-Glass-Etching-Carded/dp/B003W0MUVW