Stereolithography

By

Paul Eggerton

What is Stereolithography?

• Stereolithography, also known as 3-D layering or 3-D printing, allows you to create solid, plastic, three-dimensional (3-D) objects from CAD drawings in a matter of hours.

• “Stereolithography is a common rapid manufacturing and rapid prototyping technology for producing parts with high accuracy and good surface finish. A device that performs stereolithography is called an SLA or Stereolithography Apparatus.” (Wikipedia)

How Does it Work?• Stereolithography is an additive fabrication process utilizing a vat of liquid UV Curable

photopolymer “resin” and a UV laser to build parts a layer at a time.

• On each layer, the laser beam traces a part cross-section pattern on the surface of the liquid resin.

• Exposure to the UV laser light cures, or, solidifies the pattern traced on the resin and adheres it to the layer below.

More Process Info

Most SLA machines can produce parts with a maximum size of

20” x 20” x 24”.

Producing parts through stereolithography can take anywhere from a few hours to more than a day. It depends on the size and complexity of the product.

Advantages and Disadvantages• One advantage of stereolithography is that a functional part can be created within one

day, which is very important to businesses that are in a crunch for time.

• “Prototypes made by SLA can be very beneficial as they are strong enough to be machined and can be used as master patterns for injection molding, thermoforming, blow molding, and also in various metal casting processes.”

• Although there are almost no limitations when it comes to the shapes of the parts that can be created, the process is very expensive. “The photo-curable resin can cost any where from $300 to $800 per gallon. An SLA machine can cost from $100,000 to $400,000” (Wikipedia)

Works Cited

• en.wikipedia.org/wiki/Stereolithography

• computer.howstuffworks.com/stereolith.htm