Versatile manufacturing has always been important to RS Coatings Ltd., based in Lichfield, Staffordshire, UK. Since opening its doors in 1999 as a division of masking-jig specialist RS Composites Ltd., the company has manufactured and coated plastic components in low, medium and high volumes for a wide range of customers.
One customer is a Tier 1 electronics manufacturing services provider, to which RS Coatings supplies nearly 300 enclosure sets for communications devices each day. The electronics manufacturer installs all internal components in each set, and then sends the finished product to a telecommunications provider that sells the devices primarily to stock exchanges and brokers worldwide.
The enclosure’s top cover features several transparent polycarbonate areas for LCD text display screens. For many years, RS Coatings joined the top and bottom covers with various-width adhesive tape strips that were placed at specified contact areas. Unfortunately, this approach was labor intensive and operator dependent, as the strips had to be manually cut to the desired length and applied.
To increase productivity, RS Coatings’ technical department reached out to the 3M Co. for advice in 2011. Industrial adhesives and tape specialists there recommended RS replace the tape strips with the company’s series 9087 double-coated tape. This 10.2-mil-thick tape features adhesive on both sides of a 1.5-mil-thick PVC carrier for easy handling. It offers high peel and shear strength, and excellent resistance to UV light, solvents and plasticizers.
RS Coatings designed various die-cut forms of the tape, which proved more user friendly and increased contact surface between the transparent areas and front covers. The company then wanted to further maximize adhesion between components.
3M engineers suggested coupling the 9087 tape with Scotch-Weld DP807, a two-part methyl methacrylate acrylic-based adhesive that reaches handling strength in 15 minutes. It also offers high overlap shear and peel strength, as well as excellent durability on most plastic surfaces.
Assemblers dispense DP807 with an EPX II Plus applicator featuring a mix nozzle. RS Coatings likes that the product requires minimal surface preparation. It has a 1-to-1 mix ratio, a 5-minute work life and comes in containers of 47, 200 and 400 milliliters.
“Overall, the bonding system more than meets expectations,” says Laurie Richardson, managing director for RS Coatings. “The die-cut tape enables a quicker and easier application while reducing waste. Using it in tandem with the adhesive creates a far stronger bond.”
Richardson points out that there have been zero failures of in-service enclosures since RS Coatings began using the adhesive products in tandem. She says the company is looking at automating the adhesive application process.
White in color, the 9087 tape contains Adhesive 375, which provides quick stick and good adhesion to both high- and low-surface-energy substrates. Its excellent initial tack ensures that a bond of good integrity is achieved soon after application. The tape joins components of various materials to smooth, rough or textured surfaces and substrates.
For more information on adhesive tapes and methyl methacrylate adhesives, call 888-364-3577 or visit www.3m.com.