hello all ,
i want to make cufflinks ,
and rings ,
i can make up stones and pendants with dichroic glass
but some of the new sterling finding i have purchased have besels ,
at the moment i have been cold working the cabashons to fit into the bezels , which can take a bit of time , for the cuff links and rings
and as i know coming up to shows i will be busy , i am trying to find out if i can make a multiple mould of some( i no nothing about making moulds )
and lay the dichroic into them ( i attempted cutting the shape in fibre paper , but they came out with a rough surface
does anyone do this , ? cast small jewellery components
or should i not try this method , i value your advice
many thanks
evsirl
i need help ! is it possible to cast a cabashon
Moderator: Brad Walker
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Jerry Cave
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evsirl - Of course you should try it. Casting small objects works just fine. A good friend who I got started in fusing is now casting some of her work. She still fabricates the settings however. I cold work every piece I make, then fabricate or cast the setting in silver or gold. Unlike precut stones, glass cabs tend to vary a wee bit in size. I'd think kiln casting might be the only way to maintain consistant sizings.
Cold working isn't so bad if you use some short cuts. Amazing how many I can do in a short amount of time.
Cold working isn't so bad if you use some short cuts. Amazing how many I can do in a short amount of time.
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Jerry Cave
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- Location: Zig Zag Oregon
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Brad Walker
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Most jewelers use a lost wax technique for casting. This is a technique that uses a wax model of what you would like to cast.
The simplest way to do this is to work directly in wax. You want to use a good microcrystalline wax (Victory Brown is the most common), or you can get a workable substitute by mixing equal parts of parafin and beeswax (both easy to find).
If you don't want to work directly with a wax model original, you have several other options. Probably the easiest is to use clay as your material. For a simple cab, simply roll out a slab of clay and then press the shape you'd like into the clay. Fill the depression with wax. After removing the wax from the clay, you can shape and smooth even more if desired. (Another approach is to make a more elaborate clay model, then use a mold material such as RTV rubber or alginate to make a wax duplicate, but this is more complicated.)
Once you have the wax in the shape you want, you can make a plaster/silica mold, melt the wax from the mold, then fill the cavity where the wax was with glass and cast. This is the basic lost wax technique.
All of this is a simplification that leaves out a lot of details, but it should give you some idea of the basic process. There are a number of different ways to cast, and every caster has his or her favorite method.
The Warm Glass website has some basic info on casting here: http://www.warmglass.com/kiln_casting.htm
Here's another page with some basic info about the process: http://users.lmi.net/~drewid/Lost_Wax_Casting.html
A good book on casting for jewelers is Tim McCreight's "Practical Casting." It's not glass specific, but it has all the basics.
The simplest way to do this is to work directly in wax. You want to use a good microcrystalline wax (Victory Brown is the most common), or you can get a workable substitute by mixing equal parts of parafin and beeswax (both easy to find).
If you don't want to work directly with a wax model original, you have several other options. Probably the easiest is to use clay as your material. For a simple cab, simply roll out a slab of clay and then press the shape you'd like into the clay. Fill the depression with wax. After removing the wax from the clay, you can shape and smooth even more if desired. (Another approach is to make a more elaborate clay model, then use a mold material such as RTV rubber or alginate to make a wax duplicate, but this is more complicated.)
Once you have the wax in the shape you want, you can make a plaster/silica mold, melt the wax from the mold, then fill the cavity where the wax was with glass and cast. This is the basic lost wax technique.
All of this is a simplification that leaves out a lot of details, but it should give you some idea of the basic process. There are a number of different ways to cast, and every caster has his or her favorite method.
The Warm Glass website has some basic info on casting here: http://www.warmglass.com/kiln_casting.htm
Here's another page with some basic info about the process: http://users.lmi.net/~drewid/Lost_Wax_Casting.html
A good book on casting for jewelers is Tim McCreight's "Practical Casting." It's not glass specific, but it has all the basics.
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Jerry Cave
- Posts: 78
- Joined: Tue Mar 11, 2003 2:59 pm
- Location: Zig Zag Oregon
Hey Brad - Glass casting is something I intend to try. Again, no experience with the process. I do cast metal and have Practical Casting in my reference library, commonly called a big stack of books. Often wondered if the investment would work, sounds like it will. Carving the model from wax would be really nice. Biggest problem with lost wax casting method are the air bubbles that form in the investment. Eliminating and removing those bubbles is almost an art form itself.
Gonna have to work this into my schedule and try small object casting. Seems like the next step for my work.
Gonna have to work this into my schedule and try small object casting. Seems like the next step for my work.
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Brad Walker
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Two things to note about casting glass versus other metals.
First, you can use plaster/silica as your investment. 50/50 or a little more silica than plaster if you want a softer mold for carving. (Unlike plaster alone, uncured plaster/silica is very easy to carve.) For small items you can get by without any other mold support.
Second, trapped bubbles are generally less of a problem than with some metal casting. I think this is because glass melts its way into the mold and the long soak gives air time to escape; with metal casting you don't have the long soak at a high temperature. I recently lost wax cast some small items (roughly 1" by 4") with virtually no bubbles and have cast small bust figures (3 to 4" across) with no problem.
First, you can use plaster/silica as your investment. 50/50 or a little more silica than plaster if you want a softer mold for carving. (Unlike plaster alone, uncured plaster/silica is very easy to carve.) For small items you can get by without any other mold support.
Second, trapped bubbles are generally less of a problem than with some metal casting. I think this is because glass melts its way into the mold and the long soak gives air time to escape; with metal casting you don't have the long soak at a high temperature. I recently lost wax cast some small items (roughly 1" by 4") with virtually no bubbles and have cast small bust figures (3 to 4" across) with no problem.
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Jerry Cave
- Posts: 78
- Joined: Tue Mar 11, 2003 2:59 pm
- Location: Zig Zag Oregon
What I'm hoping to do is cast glass using most of the lost wax techniques. Won't use the centrifuge of course. Sprue base will also change. Instead of carving investment, I'll carve wax and burn it out.
Bubbles in lost wax casting can be a problem. Generally these bubbles attach themselves to the outside of the object. Through the process the bubbles become big ugly bumps. We use a debubblizer on the model which helps. Wet investment is also placed on a bench vibrator. The vibration forces the bubbles to float to the surface and disipate. Decent vibrator goes for about $80 and is worth every penny. Another way to remove bubbles is a vacuum system, about $500 though.
Bubbles in lost wax casting can be a problem. Generally these bubbles attach themselves to the outside of the object. Through the process the bubbles become big ugly bumps. We use a debubblizer on the model which helps. Wet investment is also placed on a bench vibrator. The vibration forces the bubbles to float to the surface and disipate. Decent vibrator goes for about $80 and is worth every penny. Another way to remove bubbles is a vacuum system, about $500 though.
thank you brad for your reply !
thank you for your reply,
i like the sound of the beeswax /parrafin wax blend
i will get some and play around trying to make a mould ,
and when im happy with the mould have a go !
i printed off the replys so i can re read them ,
and also the links ,
many thanks
evsirl
i will let you know how i get on !!
i like the sound of the beeswax /parrafin wax blend
i will get some and play around trying to make a mould ,
and when im happy with the mould have a go !
i printed off the replys so i can re read them ,
and also the links ,
many thanks
evsirl
i will let you know how i get on !!