The customer is a subcontractor to the French aircraft industry. Since the application is subject military specifications, particularly high demands have to be met.
- Diameter final bore: 8.3 +/- 0.2 mm
- Diameter reverse counterbore / back spot face: 13.0 +/- 0.2 mm
- Material: Difficult to machine special steel with high tensile strength and resistance to corrosion
The particularity of this application is that the back spot face is positioned eccentric to the bore.
In order to produce this counterbore, a temporary bore with diameter 6.35 is drilled. After that, the bore will be extened to Ø8.3 taking the eccentricity into account.
For the counterbore itself, a customized BSF Back Spot Facer tool is needed because this diameter is not part of the standard range. At the same time, the working length has been adapted to the application in order to achieve an optimized cycle time.
By using this BSF tool, the customer possesses a reliable solution now. This, although the back spot face is more than double the bore diameter and the material is highly difficult to machine.