Case Study 1
Part name: Slipring
Material: Beryllium copper
Challenge: To produce a complex, intricately formed three-dimensional part to exacting tolerances with no burr, with no secondary deburring allowed
Solution: We developed our tooling using rapid prototyping to ensure proper allowances for springback and other unpredictable effects peculiar to particular spring-temper alloys. Details were EDMed from CPM tool steel with very precisely controlled, close clearances in the blanking die, a progressive die that produced the part with its five holes pierced, in-the-flat.
Secondary operation one raised the very tightly controlled toroidal annulus in the center of the piece. Forming details were ram-EDMed from D2 tool steel. To avoid damage to the piece, both secondary operations were hand-fed and hand-extracted.
Secondary operation two formed two S-shaped bends while simultaneously forming the two "trusses" formed by near-ninety degree bends. Special features of this piece of tooling eliminated "oil-canning" present in the piece from secondary operation one.
Beryllium copper presents unique challenges in any stamping operation - tool wear, operator safety, scrap minimization through strict quality control protocols (because of high material costs), and the sensitivity of the material to minor variations in cutting speed and pressure, coolant, and so on, become much more important when dealing with this material. In the case of this slipring, these challenges were compounded by the complex, tightly toleranced geometry of the part itself.