Change is the only constant. The ways shops transform a rough casting or material stock into a precision machined component–and make money at it–are different than in years past. Granted, the act of removing bits of material using some type of cutting tool is essentially the same. However, other aspects of the overall process of supplying machined parts are clearly different.

They have to be different. Consider how the needs of product manufacturers–medical manufacturers in particular–have evolved during recent years. Makers of both surgical instruments and implant devices now have need-it-yesterday delivery requirements. Prototypes must be machined in the specified material with all secondary operations completed. Component appearance is considered just as important as the accuracy of part features. Ten pieces is a large batch size.

The shops that have had, and will continue to have, success serving the medical industry are those that have not only taken note of such changes, but also have been keen enough to tweak their own processes to best meet new customer demands. One such shop is Metal Craft Machine & Engineering, located just outside Minneapolis in Elk River, Minnesota.

Things have changed since Jack Mowry opened the shop in 1978. The company has expanded five times and has added a second facility in Chippewa Falls, Wisconsin. Now approximately 95 percent of its work ships to medical manufacturers, whereas before, a large chunk of its business was geared toward the semiconductor industry. Its approach to prototypes and its method for producing such one-off parts are different. A number of secondary operations that were once outsourced or not even considered years ago have been brought in-house.

There are other changes over which the shop had no control. New materials specified for medical parts are proving more difficult to machine, and skilled labor is a scarce resource.

To succeed in serving the medical industry, shops such as Metal Craft have no choice in the matte–either adapt or say adios. However, while Metal Craft is, in effect, a “medical” shop, all machine shops should take note of how it has adapted to the changing needs of its customers. After all, the medical industry isn’t the only manufacturing segment that refuses to stand pat.

Prototyping On Production Machines

Metal Craft does have machine tools primarily dedicated to prototype work. Years ago, most all prototyping was performed on those machines. Today, the shop makes every effort to run prototype jobs through its CNC production machines, which include Swiss-type lathes, conventional lathes, vertical and horizontal machining centers (some with four- and five-axis capability), seven-axis grinding machines and wire EDM. There are a few reasons for this.

Today’s medical manufacturers want prototype parts machined in the specified material with all secondary operations completed. This rules out rapid prototyping methods using alternate or more easily machined materials. Also, the complexity of the latest part designs often precludes anything but multi-axis CNC machines to achieve the desired quality levels. Gone are the days of cobbling together a prototype that may or may not be spot on.

Running prototypes through its production machines offers Metal Craft the chance to work through issues that will only reveal themselves in production runs. This also levels the production learning curve because all aspects of the production machining process–tooling, workholding, cutting data, programming–are in the can.

Having a complete CAD/CAM program is especially helpful in getting prototypes into production quickly. Even if changes to the part design are required (to accommodate the desires of an individual surgeon, for example), a basic program framework exists that can be easily altered. Also, the need for any special tooling will have been identified during the prototyping process and the shop will then have that tooling in-house.

The fact that customers know a shop has a process ready to roll whenever they pull the trigger on a production run gives that shop an edge if and when production work comes to fruition. “If” is the key word, as there is no guarantee that production work will follow. Metal Craft works closely with its customers to determine if a prototype will be a one-time deal or if it will likely lead to a production order. The shop charges its customers accordingly.

Effectively mixing prototype and production jobs can be a scheduling headache. The ERP software that company uses, M1 from Bowen & Groves (Chandler, Arizona), helps ease some of the pain. Purchased 3 years ago, it offers real-time data collection so that a scheduler can view the status of jobs currently running in addition to the promised delivery dates of those in queue. This is helpful in terms of determining the best possible time to insert a prototype job into the production schedule.

Another benefit is the system’s flexibility. It is used for everything from data collection on the floor and quality control to payroll and accounting. Users can tailor it to their own needs, and employees can customize its look to show the information most appropriate for their job duties.