Produced by RESIN SYSTEMS, the protective enclosure for the BYK-Gardner color view spectrophotometer is a filled urethane casting that measures 12″ x 15″ x 6″ with a uniform wall thickness of ¼” and tolerances as close as +/-.005″.
Cast Resin Instrument Enclosure Safeguards Critical Spectrophotometer Components
BYK-Gardner USA of Columbia, MD designs and manufactures state-of-the-art quality control instrumentation — for example, spectrophotometers, colorimeters and gloss meters. These are used in many different industries for measuring the physical appearance characteristics — color, gloss, and texture — of a multitude of products.. Typical users of these instruments include manufacturers of paints, inks, plastics, textiles, food and pharmaceuticals.
One of BYK-Gardner’s newest systems, the color-view spectrophotometer, features a relatively large, fully-visible, protective enclosure measuring 12″ x 15″ x 6″ with a uniform shell thickness of 1/4″ and tolerances as close as +/- 0.005″. Because the instrument has a self-supporting chassis, the enclosure needs only moderate structural strength — its primary functions are to keep the internal components of instrument clean and dust-free, and to cosmetically enhance the appearance of the system.
The Challenge:
Overcoming Delivery Delays and Part-to-Part Inconsistency Problems Experienced with Fabricated Enclosures
“Originally we considered forming the enclosure by plastic injection-molding,” explains Rick Trawick, BYK-Gardner’s Manufacturing Engineering Manager. “However, the cost of tooling for injection molding proved prohibitively expensive. As a consequence, the prototypes for the enclosure — and the initial production runs — were completed as assemblies fabricated from machined and glued PVC plates.”
According to Trawick, “These fabricated enclosure assemblies were expensive to manufacture and comparatively fragile. Moreover, delivery often fell several months behind schedule and there was a significant part-to-part inconsistency problem.” Collectively, these problems threatened to impact BYK-Gardner’s ability to keep up with its backlog of new orders for the color-view spectrophotometer.
The Solution:
Durable, High-Quality Cast Resin Enclosures Offer Superior Part-to-Part Uniformity; Meet Predictable Delivery Schedules
For BYK-Gardner the solution to their problem came when a sales representative for RESIN SYSTEMS CORPORATION brought in some samples and proposed using liquid resin casting for the enclosure instead of plastic fabrication. “Although BYK-Gardner had never used liquid resin cast parts before we thought the process had some compelling advantages that justified giving it a try,” says Trawick.
According to RESIN SYSTEMS Engineering Manager, Stuart McCord, “BYK-Gardner discussed design and material requirements with us, and contracted for RESIN SYSTEMS to produce the enclosures. To facilitate installation on the color-view spectrophotometer, it was determined that the cast resin enclosures would incorporate cast-in threaded inserts and be subjected to some minor secondary CNC machining.”
“By using an aluminum mold, we can provide excellent dimensional accuracy (+/-0.015″ over a 14″ distance, with some tolerances as tight as +/- 0.005″ over 5″) and achieve the required part-to-part consistency and repeatability,” McCord notes. “After a short prototype development period of two weeks during which we modified the resin formulation and molding techniques, the enclosures entered production. Made of filled urethane, the enclosure is produced at a rate of 250 parts per year per mold.”
“The change to liquid resin casting immediately resolved the back-order bottleneck,” says Trawick. “The cast resin covers display excellent uniformity from part-to-part and lot-to-lot, and BYK-Gardner is assured of receiving steady, reliable, and predictable deliveries against our production schedule. I wish we had found out about liquid resin casting years ago. There are many things we could have done with this process. For us, it opens a lot of new avenues for production.”
