Investment Castinga presentation by

Cheryl Feldman and Dan MarioniEngineering 45 MaterialsSanta Rosa Junior CollegeInstructor: Younes Attiayan

Fall 2007

Casting Casting is a process by which a molten metal or

material in its liquid state is poured into a mold and allowed to become solid in the shape of the mold. The mold is then broken from around the solidified part or complex shape.

Casting is used to create more complex or detailed parts that would be difficult to manufacture using other methods.

The cast is built so that the inside is the shape of the part that is being manufactured, then the molten metal or liquid material is poured into

the space provided.

The History of Casting Metal Casting has been dated back to the Neolithic

period (6000-1800 BC). Castings were made in order to create necessary

tools and equipment used in the newly born establishment of village settlements and agriculture.

By 4000 BC, earrings, hairclips, and needles were being made and demonstrate advanced techniques of copper casting.

The techniques that are being used today in industrial casting were developed two thousand years ago.

Sand Casting For hundreds of years it was the most popular of all

casting methods. It still plays an important role in the production of large metal forms, and can offer the advantages of low cost, quick results and ease of duplication to those goldsmiths who take the time to master it. Though sometimes thought of as coarse, sand casting can yield results that are as fine and true to detail as any other casting method.

Melting the Metal Common ways to melt certain metals Large forges either arc or gas fueled (C3H8) Can be purchased small scale Most popularly, home made. Graphite pots, coffee cans, BBQs Basic Diagram:

Air duct(bottom) Coal

Crucible

Lost Foam (LFC)Fabricated Foam Patterns

has the ability to overcome many of the problems associated with the other prototyping processes.

Styrofoam commonly used (expandable Polystyrene)

The advantages lie in the ability to make larger parts, to make iron castings and to make prototypes in a production facility with production techniques.

http://www.holisticforgeworks.com/gallery/foundry/

LFCError…

http://web.umr.edu/~foundry/

Dimensions (in.) Tolerance (in.)<1 +/- .0071 to 3 +/- .0103 to 5 +/- .0125 to 7 +/- .0177 to 10 +/- (in. x .003)>10 +/- (in. x .002)Rough Estimate: <7 in. +/- .015 >7 in. +/- .003 in./in.

Investment Casting Commonly referred to as “lost

wax” Longest known form of casting

approx. 6 millennia for sculpting and jewelry

Mold is made from wax (b/c of low melting temperature)

Slurry is applied to the wax Wax melted out Result: perfect cast for pouring

metal For max. profit, many are

designed together in what’s known as a “wax tree”

For example, New Horizon Inc. states the minimum casting lineal dimension tolerance can be under 0.10mm, and surface roughness can achieve Ra1.6-12.5um.

Also commonly preformed at home…

http://newhorizonco.com/products.html

Casting Today… Used in many industrial situations Individual jobs which require a high degree of

precision A look into the Industrial World of Casting: http://www.milwaukeeprec.com/video.htm

http://www.youtube.com/watch?v=3k5rgMBwpFU

Investment etc. Some types of investment casting

are also Centrifugal, and Vacuum assist

New molding: What about intense molds? High accuracy and can’t have room

for error??….. zp 14 Investment Casting Material

can be used to quickly fabricate parts that can be dipped in wax to produce investment casting patterns. The material consists of a mix of cellulose, specialty fibers, and other additives that combine to provide an accurate part while maximizing the absorption of wax and minimizing residue during the burn-out process

http://www.youtube.com/watch?v=hkPWnZWo2cc&NR=1

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

3D PRINTING

In addition:Youtube!

There’s a plethora of information at our finger tips

In other words: VISIT YOUTUBE!

Hundreds of casting videos of all shapes and sizes.

Our Project

Preparing our molds

Melt wax out of mold

Last step was to mount the Plaque on anotherPlate of plaster for a “cleaner” look.

Sources

http://web.umr.edu/~foundry/ http://www.holisticforgeworks.com/gallery/foundry/ http://impudent.blognation.us/blog/Photos/_archives/2005/12/14/1449621

.html http://www.milwaukeeprec.com/video.htm http://www.nyu.edu/its/pubs/connect/fall06/gibbons_printing.html http://www.youtube.com/watch?v=hkPWnZWo2cc&NR=1 http://www.nyu.edu/its/pubs/connect/fall06/gibbons_printing.html http://www.youtube.com/watch?v=3k5rgMBwpFU http://en.wikipedia.org/wiki/Investment_casting