STEREOLITHOGRAPHY (SLA)



	Photo used by permission of Carling Technologies

InterPRO ships most Stereolithography (SLA) prototypes 2-3 days after you place your order. Larger models can take a bit longer.

We finish all SLA models to your specifications - from a basic fit-check model to a beautiful "show" model with custom paint, textured finish and graphics. We can even add metal plating for increased functional strength, conductivity or a brilliant chromed appearance.

SLA models are inspected to the digital file that you supply, and assemblies are tested for proper fit. Models larger than 24 inches are built in sections, and bonded with reinforcing pins for accuracy and strength.

We always pay close attention to the details on your model and take care to preserve all features.

THE SLA PROCESS

SLA builds plastic prototypes with high accuracy, excellent detail and great surface finish. It is the most commonly used rapid prototyping technology.

SLA builds parts one layer at a time by tracing a laser beam on the surface of a vat of liquid photo-polymer. The polymer is solidified by the laser light (not by heat).

After each layer is traced, it is lowered a small distance into the liquid and the next layer is traced, bonding to the previous layer.

After all layers are traced, the completed 3D model rises from the vat to be removed for cleaning and careful hand finishing.

APPLICATIONS

SLA prototypes are used to evaluate product appearance and verify assembly of components.

They are also used as functional prototypes, as patterns for metal castings, and as patterns for creating RTV rubber molds, injection molding core and cavity inserts, thermoforming molds, blow molds, plaster molds, and roto-molds.

FINISHING LEVELS AVAILABLE

Basic - We remove supports, then cure the part. Minimal finishing is done. Good for "Do It Yourself" customers who like to do their own finishing.

Standard - After doing a Basic finish, we lightly sand the model to remove build lines on exterior and other important interior surfaces. Then we satin finish it with a glass bead blast.

Mold Finish - After doing a Standard finish, we further smooth the model and gray primer.

Custom - Appearance ("show") models that are expertly finished to a high level, to match the look of actual products. Color matching, texturing and graphics are custom quoted.

TOLERANCES

Standard Tolerances that you can expect on SLA models are:

In X/Y: +/- 0.005" for the first inch, +/- 0.001" for the each inch thereafter.
In Z: +/- 0.01" for the first inch, +/- 0.002" on every inch thereafter.

Available Layer Thickness are:

High-Resolution: 0.002" - 0.004";
Standard Resolution: 0.006"

SLA MATERIAL SELECTION

Currently InterPRO is offering the following choice of SLA rapid prototyping resins

SOMOS 11120 Watershed - a strong, robust material with excellent accuracy and good for snap fits. With the addition of a clear coat paint, the material becomes almost glass clear with a slight green tint. It has many properties that compare favorably to ABS. It is also resistant to humidity and moisture. See the SOMOS 11120 Material Properties Sheet (PDF - 577KB).
SOMOS 14120 White - This is an opaque white version of SOMOS 11120 Watershed, with almost identical properties. See the SOMOS 14120 Material Properties Sheet (PDF - 273KB).