Flexibility of CAD/CAM Helps Toolmaker Land Boeing 777 Tooling Project

The seal measures three by three metres square, and has a small and variable cross-section.  Like many of the company’s projects, the molds and the associated checking fixture were supplied to Meggitt Polymers and Composites.

“When the Boeing representative visited us, he seemed a little nervous about having a relatively small company responsible for the tooling for such a critical component,” admitted Myles Ball, Managing Director at Tower Tools.  “He was a lot happier when the first seal was delivered in 18 weeks, six weeks earlier than the norm for a seal of that size.  In addition, the seal fitted perfectly and worked first time.”

Tower Tools has specialized in molds for rubber products, in particular for aerospace seals, since it was founded in 1957 in the center of Leicester.  The company took its name from the nearby clock tower.  It moved to its present site in 1995, where it has bigger and better premises with easier access to the motorway network.  Meggitt, together with GKN and Trelleborg, are the company’s major customers, but it also undertakes work in other transport sectors and for medical applications.

Unlike many customers who have bought Delcam software after a recommendation from an existing user, Ball first invested in the software in 1998 after speaking to a company that had decided on a cheaper CAD/CAM package.  “The owner told me that he had made a big mistake and that he wished he had paid the extra for the Delcam system,” remembers Ball.  “From that moment, I knew I had to have Delcam software.  The demonstration convinced me; the software seemed to be far more intuitive than the other packages I’d seen.”

Comments from a Delcam user were important when new Engineering Manager, Andy Lowe, arrived at Tower Tools and began using the PowerSHAPE design software.  “I found PowerSHAPE to be very different from the system I had used previously,” he explained, “but a sub-contract draughtsman that we used told me it was the best system for tooling design so I stuck with it.  Ironically, I became so much more productive once I got used to the different way of working that we didn’t need to subcontract as much of our design work.”

“The flexibility of the software is important to us,” adds Ball.  “For some projects, we are supplied with a fully-detailed CAD design of the seal so we use PowerSHAPE just to create the mold.  At the other extreme, we can be sent drawings of two adjacent parts and are told to create something to fill the gap between them so we need to design the seal from scratch.  PowerSHAPE also makes it very easy to make checking fixtures from the tool designs.”

“The PowerMILL CAM system also gives us many benefits, not least the ability to machine undercuts in three-axis by using special cutters,” he continues.  “The flexibility of rubber means that undercuts are far more common in rubber molds than in those for plastics.”

“Even more important has been the support that we have received from Delcam,” he concludes.  “Whenever we have any problems, the help-desk staff go out of their way to help us.  The regular training days are invaluable in keeping us up to date with developments in the software and the latest design and machining techniques.”