Study. Control. Improve.
Being able to do these things is the reason why keeping a critical process in-house is important to many manufacturing companies. Because product quality often hinges on a synergy between many steps, it's risky to have even one of these steps under an outside party's sway.
The problem is, some processes are so specialized or capital-intensive that bringing them in-house seems impractical. However, a company may not need full capacity to get real benefits. If you can't do it all yourself, maybe you can do just enough so that the studying, controlling and improving can take place on your own turf.
A good example of this approach is being implemented by machine tool builder Mori Seiki. The company is building its own foundry and heat-treating facility at its main manufacturing complex in Iga, Japan. The heat-treating facility will have the capacity to handle about 40 percent of monthly heat-treating demands. The foundry will have the capacity to produce about 35 percent of the company's needs. Neither facility will be large enough to provide all of the company's casting or heat-treating requirements, but the facilities will let the company explore ways to make the processes more effective and less costly.
Reducing distortion, stress and inconsistency is one of the targets in the heat-treating operation. Making castings lighter, more rigid and less susceptible to the effects of heat is one of the goals for the foundry. Because castings are the foundation for machine tool performance, this latter goal is particularly critical. Having a foundry on site will also reduce leadtimes for cast components and speed prototype development.
The value of having a process in-house was demonstrated a few years ago. The company installed a sheet metal operation to produce machine enclosures and guarding. Experience with laser cutting and bending gave the company a clear idea of production and cost benchmarks. This helped the company evaluate subcontractors and make scheduling more accurate. Speeding prototype development and improving design for manufacturability were also benefits.
There are lessons here for every manufacturer. No part of the production process should lie outside the company's efforts to reduce waste and improve quality. Get as close to every production step as possible, by doing at least some of the work in-house, or perhaps by working very closely with a supplier or provider partner.