Archive for the ‘lost wax casting’ Category

ART HELP !!!!!!!!!!!!!!?

February 20, 2010 - 5:27 am 1 Comment

1.The process of painting a mixture of pigments and hot wax, which left a shiney hard surface when it cooled is called:
a.encaustic
b.frescoe
c.entasis
d.gloss coating

2.Mosaics are created from small cubes of colored stones or marble called:
a.tempera
b.torques
c.stele
d.tesserae

3.One characteristic of Hellenistic art was when the artist tried to elicit a specific emotional response in the viewer and this style of art was called:
a.emotionalism
b.expressionism
c.realism
d.ebullience

4.Which of the following is NOT one of the three main techniques for decorating Greek painted vases:
a.red figure
b.black figure
c.black ground
d.white ground

5.A process used for making fine jewelry in the Greek goldsmith shops is known as:
a.lost wax casting
b.encaustic
c.kiln molding
d.himation firing

Section?

How much jewelry making can I do at home with minimal investment? (not beading)?

February 18, 2010 - 8:20 am 1 Comment

When I was in high school I took a jewelry making class where we would make all sorts of jewelry. We did lost wax castings to make rings. We took and cut out metal sheets into designs and etched them. Even took stones and turned them into pendents. We sauntered metal and polished them with what I believe was a dremel. Anyways, I really enjoyed that and would like to take this up as a hobby.
I know the lost wax casting isn’t practice, but I really think the etching and even stone setting could be. I just don’t know where to begin to aquire the tools and supplies. Since the teacher provided everything, and this was 10 years ago, I am not sure I know all the supplies I would need either. I know I’d need a jewelers saw, but that is about all I remember.

Is this really possible and if so where do I begin?

This is absolutely possible, but you do need some basic equipment. You’re right, a jeweler’s saw is a must, but for starters just get a bundle of #2 blades – these always come in dozens and you can get away with just a medium kerf. A torch is also a necessity. Start with butane or propane and use very low temp solder – the kind that contains silver and is labeled lead free. As for materials you can experiment with german silver (actually a nickel alloy with no silver) or even tin. A good source of german silver is Metalliferous (google it) in New York. Also they are a good source for tools – but you can find the basic stuff at a hardware store. As you get more advanced you will have to upgrade your torch anyway. An alternative to lost wax casting is precious metal clay (PMC). It is a silver bearing moldable clay which when fired with an ordinary propane torch becomes pure silver. Check out "Whole lotta whimsy" on the net. Have fun.

please answer quickly asap please hurrry please?

February 16, 2010 - 7:08 am 1 Comment

Which statement describes a characteristic of Islamic tughras?

(Points: 3)
Artists depicted the names of common citizens using calligraphy.

Artists used images of plants, animals, and humans.

Artists included text and images from epic stories important to Muslims.

Artists used complex arabesques and interlaced lines.

13. Which of the following is a convention Kuba artists of Africa used to decorate ceremonial masks?

(Points: 3)
sewing shells and beads with symbolic meanings onto the mask

wrapping horse hair with raffia to create stiff fringe

sewing human hair onto the top of the mask to create height

tying brass bells on the base of the mask to create sound when performers danced

14. Which statement describes a characteristic of chi wara masks made by Bamana artists of Africa?

(Points: 3)
Artists carved lifelike creatures to represent Islamic ideas.

Artists inscribed the base with calligraphic script and floral designs.

Artists used the forms of an antelope to create masks used in farming celebrations.

Artists used beads, shells, bits of brass, and other natural materials as decoration.

15. In what way are the Seated Buddha in China and the Indian sculpture Shiva Nataraja similar?

(Points: 3)
Artists featured important Chinese and Indian emperors.

Artists used symbols that reflect religious beliefs.

Artists made them using the lost-wax casting technique.

Artists created them to reflect political beliefs of their cultures.

16. Which of the following statements describes a difference between the Maya sculpture of Lord Pacal and Yoruba sculpture of an oni?

(Points: 3)
The Maya sculpture is a lifelike portrait without idealization; the Yoruba sculpture is an abstract portrait.

The Maya sculpture was made by carving fine plaster; the Yoruba sculpture was made using the piece-mold casting technique.

The Maya sculpture has symbolism linking Pacal to the Maize god; the Yoruba sculpture has symbolic lines representing scarification or a beaded veil.

The Maya sculpture was carried in processions honoring Pacal; the Yoruba sculpture was placed in front of the oni’s palace as propaganda.

You need to find teh answers in your text book or in your class notes. Otherwise, you won’t either remember or understand them.

Step 6. Lost wax Casting reproduction using wax injection. 21083

February 16, 2010 - 1:18 am 5 Comments

This is the sixth step in the reproduction process I use for making my jewelry. After the molds have been fully de-waxed and tempered in the furnace for 12-24 hrs the molten metal is poured into the molds.

Duration : 0:1:45

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What molds do you use for brass casting?

February 14, 2010 - 5:12 am 3 Comments

I have casted brass twice useing the lost wax method and I am useing plaster molds. Each time after the brass is dry I get a piece of brass in the shape of my mold, but also with little holes like pock marks all over it. These marks are to deep to grind away. I also get in some places just crumbled metal. I thought maybe it was the mold I was useing, but then I also thought it might be the dross of the metal clumping together and making this happen.

hi tim, do you throw something like borax into your molten brass in order to get the slag to rise and do you skim this off and throw it away? This should get rid of the impurities in the metal. From what you describe this may be part of your problem.
Another possibility is that your wax isn’t completely burned out and when it burns out because the hot metal hits it a lot of gasses develop, but can’t escape properly through the solidifying metal. You get very spongy pieces of metal this way. That’s most likely the case where your metal is crumbly. Depending how much wax is left you can even create a nice volcano…
Burn out at 1100 deg Fahrenheit for at least 12 hrs if you can afford that. If you get much hotter than 1200 F, however, your mold will start disintegrating.
Another possible problem is how you located your vents and if you got enough. If you place vents incorrectly or don’t have sufficient ones, you get problems with trapped air, though that usually just results in incomplete castings.
If your metal is too hot, you can also get porous castings.
Usually investments for castings (your mold) also contain silica sand, for that increases the thermal resistance of your plaster. But then there are also very specific mixes (e.g. Kerr’s satin cast) which make very good molds. They are made for casting jewelry. They are not as cheap, but are good to use for small things.
As ideally you would go through the entire process with somebody experienced for troubleshooting, you may want to take a class in metal casting, maybe the art department of an university not too far away has one on offer. You could also check with local foundries if you could get some experience in exchange for helping out. They are usually not that keen on it, but with some persistance and willingness to do also some boring jobs you should manage.
Have fun with your metal castings

next step in the lost wax method?

February 11, 2010 - 8:56 am 2 Comments

i am new to metal forging and casting and have opted for the lost wax method.

i have carved and casted my first piece, I need 50+ more "copies" what do i do next??

Do i do a 2 part mould of my first cast then use that as a negative, but then what??

Make more wax from that mould?
Use the 2 part mould to cast directly into?

do i make 50 mould’s and smash them all off after casting or is there a better option.

The cast is a 3inch challange coin that has 3D graphics on one side and writing on the other, it is casted in aluminium and i need a 50 run minimum dependen on the sucssfulness off them could go up to 250 run.

You make a flexible mold of the original using latex rubber molding compound or silicone rubber casting compound. http://www.sculpt.com/ With latex, you make a backing of plaster so it doesn’t flex. Then you cast as many duplicates in wax as you need. This link http://www.mikegigi.com/castgobl.htm#LATEXMOLD is to my page on molding compound and shows making multiples of bigger things that are wax welded together.
In the case of coins, after cleaning up the waxes, you mount several of them between a pair of connectors so you have a sprue to each one and a vent from them. http://www.mikegigi.com/castgobl.htm#SPRUING For aluminum, you have to provide an extra supply of aluminum in a funnel shape or riser for make-up as it shrinks in the hot mold.
You then mount the item (see elsewhere on the pages linked above) and pour in investment. After cooking out the wax you heat the investment to its peak temperature to "cure" it and lower the mold to casting temp, which is about 400F for aluminum.
You then melt the aluminum, trying to get not far over of the melting point (i.e. don’t over heat) There is deoxygenator available for less porous aluminum http://www.budgetcastingsupply.com/ and down page.
After casting, you take out the assembly, wash it, and cut the sprues and vents off and clean the edges where they were attached. It really helps to plan the removal cuts when attaching the sprues/vents. Do any additional clean up needed.

The Art of Lost Wax Casting, Part Two

February 10, 2010 - 7:43 am 8 Comments

Shows an artist creating a bronze sculpture through the lost wax process, from concept through completion.

Duration : 0:9:0

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Can wax be rotomolded for sculpture?

February 8, 2010 - 11:22 pm 1 Comment

In the lost wax process for bronze sculpture casting can a wax pattern be rotomolded ? Has anyone tried this before?

If you look at microcrystaline waxes or generally for waxes used for making jewelry, there are a considerable variety including ones for machining, carving, casting, and hand molding. Some machinery sites (MSCdirect.com I think) have blocks of wax for training people to machine metal without the expense or risk of damage to machine or operator from starting on metal.
Reviewing this article http://en.wikipedia.org/wiki/Rotational_molding shows that wax and chocolate were first uses of rotomolding and chocolate continues. There is not reason it couldn’t be used for lost wax.
I have made wax shells in the same plaster molds I used for slip casting clay – pouring in wax, rotating the mold by hand and pouring the excess out – getting a very uniform layer. see here http://users.ticnet.com/mikefirth/castgobl.htm#LGGOBPROJ and up and down that page. Any method that makes wax pieces to be added to sculpture lost wax seems perfectly legitimate to me – see 3 molded hands welded to make goblet stem, etc.

In a multi-step molding and casting process, presumably the results of each step have name; what are they?

February 4, 2010 - 6:43 am 2 Comments

I have been doing a bunch of step-by-step lost wax casting and writing descriptions of it. I find I am using the same words for results at different steps, which becomes awkward if I want to refer back to a previous step. There are probably nice standard names but I don’t know them because of being self taught from a variety of sources.
Like this
1. Make a clay model that represents 1/3 of the final object. Positive?
2. Coat this with latex molding material to make a negative copy. Negative? Soft Negative?
3. Back the latex with plaster to support it. Support Negative?
4. Pour wax into the supported mold. Wax Positive?
5. Repeat to make 2 more copies.
6. Use heat to weld the 3 pieces into a wax – what? Positive, Wax Original?
7. Add venting and sprues for casting. Call it?
8. Encase the wax positive with investment. Mold!
This gets a more complicated when the surrounding for the wax is in sections as in making a large statue.
9. Heat to melt the wax out
10. Remove the investment and clean up the result – casting!
On big items, the casting is done in sections and they are welded, braised together so more names may be needed.
Names or sites with a set of steps with names would be helpful.

Hi, I’ll help out as best I can!

1. I would call the clay model the original from which the 3 wax pieces are made (i want to call it the master model, but you might get confused with no. 2)

2. Latex master mold…the mold from which the sculpture is cast in wax form.

3.I would call this stage the plaster reinforcment of latex master mold.

4. Wax positive I think is the correct term.

6. The joining and cleaning of the pieces to make the ‘final wax model’ is called ‘Chasing’.

7. This process is called ‘Spruing’ i’m not sure if that spelling is correct!

8.Creation of the final multi-piece plaster mold.

9. This is called ‘burn out’ even though it’s actually melt out!

Step 1. Lost wax Casting reproduction using wax injection. 21083

February 3, 2010 - 12:20 am 13 Comments

This is the first step in the reproduction process I use for making my jewelry. The injection machine I have is made by Jelrus/Romanoff. I have the best success injecting at about 12-14 psi.

Duration : 0:0:35

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