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5

Glass has a melting temperature of around 1400-1600°C (see here ), and most household ovens top out at around 200-250°C so no, you cannot melt glass in a normal home oven.


4

The results may depend a lot on luck, practice, and trial and error. You might need access to a machine shop to prepare whatever will serve as the "mold". I wouldn't count on using a process that requires trimming after the glass is cool. The glass can build high internal stress as it cools, and it may have a tendency to shatter if you try to trim it. ...


4

I've never tried this, so this answer will be largely speculation based on the physical properties. You can leave a void, but I don't think you would be able to make the void a complex or delicate shape. There are a few ways to start with a well-defined void: engrave it into one or both mating faces of two pieces; start with three pieces and cut the shape ...


3

There are no tell-tale signs that a piece will crack, but there are definitely certain things that can lead to a piece cracking when fired. Significant variation in thickness from the thickest to thinnest areas of a piece (a ballpark for this might be if the thickest area is more than twice as thick as the thinnest area). Also, cracks can propagate from ...


3

Yes. Look out for "veins" in the clay as it is altered and manipulated from its original resting state. Veins might also look like threads or mini cracks.


3

If the kiln is rated for 1950 degrees Fahrenheit, then that's about the highest you should fire it to. The number of rings you use isn't a function of how hot it gets but more a function of how much space the inside of the kiln will have. To test the kiln, you can just plug it in and turn it on, if it heats up, it works. As BrownRedHawk stated, you should ...


3

Revision based on comments on the question. This answer originally suggested a microwave kiln. Then I saw the discussion in the comments. To start with the bottom line, you can't melt wine bottles in a household oven. If those are the only kind of bottles you are interested in, that's the end of the discussion. However, you could probably do it with "...


3

If you are trying to slump glass into a form then, your oven, which can reach temperatures of 500 degrees may not be the answer. That said you could use your oven to raise the temp of the glass, remove it and use a propane torch with mapp gas to complete the process. This is a convoluted and potentially harmful/dangerous method, so plan your strategy well, ...


3

Firebrick are thermally stable for the temperature range they are specified. However , some materials may cause chemical changes in certain types of fire brick and develop lower melting phases. I am thinking of glazes dripping onto brick. The normal Nichrome elements will not do this. Also silicon carbide elements will not deteriorate the brick.


3

The simple way to keep the form thin is to under fire it. If you fire to less than a full fuse the tension won’t pull the glass up to the 6mm height. If you have fine fruit or powder you can use a binder to make a paste before forming and get quite a bit of control (see pate de verre). This will leave some texture that you may not find desirable. To create ...


2

Your firebricks will already have been fired, I'm not sure anyone makes kilns with green firebricks, they would move around when firing. On the other hand if you have used fire clay , fire cement, or refractory cement to put your kiln together, then you need to ramp temperature slowly , fire clay cures with heat using the appropriate temperature and ramp ...


1

A fully encapsulated void in thin glass is difficult to impossible to do hot in a kiln. A carved out indentation open on one side is trivial. You could the encapsulate it by cold-fusing (i.e. gluing) another sheet of glass to the back. For a design such as you show I’d kiln carve it by cutting the design out of ceramic fiber paper, placing a double sheet of ...


1

The problem could be the Kanthal ( Fe, Cr, Al ) elements. Although they will tolerate a little higher temperature , they are "delicate" compared to the Nichrome type elements. Most consumer heat elements are Nichrome because it will tolerate more abuse ( eg. range elements). Kanthal becomes very brittle once it has been heated. Also it is weak when hot so ...


1

When the elements are connected directly to power, the only limitation is the inherent resistance of the elements. Ohm's law states that current is inversely proportional to resistance. The elements are going to be low resistance, which results in high current, and high heat, of course. Unfortunately, in your situation, the high current exceeds the capacity ...


1

Try using the glass beads without grinding them to a powder first. The spaces between the spheres would then give you the pores you are looking for. Alternately you could mix in a material with a higher melting point to create gaps, being sure you do not fire above what is needed to fuse the lime glass. The risk here is different expansion rates between the ...


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