STEREOLITHOGRAPHY (SLA)

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.

InterPRO offers standard resolution and high-resolution SLA models:

• Standard Resolution: In our large vat SLA we build parts at 0.006" layers with a 0.008" beam spot.
• High-RES:  Our High-RES SLA systems build at 0.004" layers with a 0.004" beam spot.

FINISHING LEVELS AVAILABLE

Basic Gloss - We remove supports, then cure the part. The model is lightly sanded. A gloss acrylic clear coat is applied.

Basic Satin - We remove supports, then cure the part. The model is lightly sanded. The surfaces are glass bead blasted.

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

Master Finish - After doing a Premium finish, we follow up with a 600 grit sandiing and gloss clear coat.

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.

Tip: If your model is to test fit or evaluate shape, you can select Basic finishing for lower pricing and faster delivery.  See our gallery for examples of our work and see finishing examples at InterPRO SLA finishing options

TOLERANCES

Standard Tolerances that you can expect on SLA models are:

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

Part geometry and build orientation can have an effect on tolerances also.

SLA MATERIAL SELECTION

• Watershed 11122 XC — a near colorless version of the best-selling ABS-like WaterShed 11120 material. WaterShed XC delivers the exceptional functionality and versatility of WaterShed 11120, but produces parts that look more like true, clear engineered plastic. This makes it highly suited for parts such as lenses or clear covers for automotive, medical and consumer product applications. See Watershed XC 11122 Material Properties Sheet

• Huntsman 7811 White — InterPRO now offers Huntsman 7811, a white SLA material with ABS-like properties. Prototypes built with Huntsman 7811 material are strong, with great surface quality and feature definition.  Snap fits work well with this material and they look really great. See Huntsman 7811 Material Properties Sheet