By Jim Johnson
Senior Technical Service Engineer
Lati USA Inc.
Mount Pleasant, S.C.
EDITED BY STEPHEN J. MRAZ
There are many ways to gain speed-to-market for OEM design engineers, material specifiers, and manufacturers of plastic components and products, especially electrical and electronic products. Here are a few tips that should help:
Here are a few tips that should help:
Push concurrent engineering to the limits. Get design, material specification, tool design, and manufacturing people involved at the outset of a project. This step alone can cut development time in half. In one instance, a wheelchair designer specified spin welding to join two asymmetrical parts. Thanks to concurrent engineering, a manufacturing person spotted the problem at an early stage and suggested adhesive bonding instead. This eliminated a manufacturing problem that would have delayed full production.
Telescope, telescope, telescope Often you can fold one phase of a project into another. For example, mold-flow analysis and structural analysis can be done simultaneously, cutting development time by several months.
Engineering teams should consider starting the mold before finishing the part design. Sometimes you can start building cavity-sinking tools as soon as there is a functional design, and then adjust a radius or thicken-up a wall later. Also, start material development along with product design. Getting material vendors involved early always improves time-to-market. Another hint: Work color-matching and part design in parallel.
Define all project specs at the outset Have all key elements ready when the project begins (i.e., physical, mechanical, chemical, thermal, and electrical requirements, flame retardancy, and UV resistance). This reduces the risk of false starts, design creep or "band-aid" solutions. (To help identify key elements at the outset of a project, Lati has developed a quality-function-deployment form (QFD) which covers more than 80 key product elements. For a copy of the QFD, call (888)USA-LATI or e-mail: [email protected]
Pick material suppliers by the size of their database in your application area. Smaller suppliers can usually react faster, are more agile, and have shorter access lines. They are also more likely to have a proven material with a history, which can cut down on development time. Remember, the more sophisticated or highly engineered your component, the bigger difference this makes.
For small-volume runs, where application support is needed, go to a small compounder You'll get faster service, including answers to design questions as well as raw materials.
Look for a standard grade, or slightly modified standard grade. This always saves time, money, and guesswork. The greater the supplier's depth of grade within a polymer family of interest for your application, the greater the odds you'll find a standard solution.
Compare vendors for turnaround commitments on support services. Knowing a vendor's exact turnaround times for mold flow analysis, stress analysis, samples, and other support services can reduce development time.
Compare vendor lab support on sophisticated parts. Determine how quickly they can identify material-flow characteristics, physical properties, and other requirements. Proper lab support can cut development time and eliminate additional guesswork. A business equipment component designer, for example, had intermittent molding problems involving localized brittleness and short shots. In one supplier's lab, the problem was traced to degradation due to excess moisture. The lab suggested new venting and tightened up moisture specifications which helped the customer meet production goals once the product was commercialized.
Invite your material supplier to your molding trials. This step is beneficial, especially during prototyping. It lets the supplier see what "tweaking" can be done in processing without damaging the material. In some instances, raising the temperature or changing the injection speed, can make the process work without changing materials.
Exploit a vendor's connections for parts requiring ancillary operations. This saves time in getting recommendations for processes involving laser marking, electroplating, ultrasonic welding, or other applications. It's also important for the material supplier to know "up front" if the material must be plated, laser marked, or ultrasonically welded.