Cessna builds new jet tail in record time using Vantico's seamless modelling paste

Citation

(2001), "Cessna builds new jet tail in record time using Vantico's seamless modelling paste", Aircraft Engineering and Aerospace Technology, Vol. 73 No. 6. https://doi.org/10.1108/aeat.2001.12773fad.014

Cessna builds new jet tail in record time using Vantico's seamless modelling paste

Cessna builds new jet tail in record time using Vantico's seamless modelling paste

Keywords: Vantico, Modelling, Pastes

The Cessna Aircraft Company, one of the world's leading light aircraft manufacturers, is using Vantico's versatile seamless modelling paste (SMP) to produce 2.7m long stretch form dies for the tail cone sections of their new Sovereign jet aircraft, in a fraction of the time taken to build conventional fibreglass/epoxy tooling (see Plate 9).

The large SMP dies are reported to also exhibit outstanding accuracy (±0.25mm) because surfaces are machined directly from CAD data.

Plate 9 The Cessna Aircraft Company is using Vantico's seamless modelling paste to produce stretch form dies for their new Sovereign jet aircaraft

Cessna began using Vantico's SMP, SV/HV 4569-1 R/H, last year as part of its programme to build 12 new Sovereign jet aircraft. The Vantico two-component epoxy paste was chosen because it is easy to mix and apply over a substructure, can be machined after curing for only 24 hours at room temperature, and reportedly exhibits extremely low shrinkage along with a shore hardness of 80D.

Cessna builds its SMP models using a simple four step process. This involves building an undersized substructure on a steel plate which is then covered with SMP to a 3.8cm depth and left to cure at room temperature for 24 hours. This oversized die is then installed in a five axis mill and cut using a two or four flute high speed steel cutter. Roughing cuts are done with a 1.2cm-1.5cm depth of cut and 2.5cm stepover at 700rpm and 2.54m/min. The die's surface is then finished with a light sanding.

Completed stretch dies can, it is said, be installed in the press and used to form parts in less than one week. The dies can also be used to build trim tools.

Should any late design changes be required, Vantico's SV/HV 4569-1 R/H epoxy paste dies are claimed to be easy to alter by simply reapplying paste over a specific area, curing and then re-machining the surface to the new design. Cessna says that it expects to be able to stretch up to 3,000 aluminium tail cone skins on a single SMP die.

"When you have a new project like Sovereign, a constant goal is cost saving, but even more important is time saving. We were able to build a die in 120 hours compared with 720 hours for traditional composite dies" explains Larry Stephens, tooling manager at Cessna. "A further benefit of the SMP dies is that multiple tooling generations, which can diminish tolerances, aren't required. And because a master model isn't needed, the dilemma of tool storage is eliminated.

"Vantico's SMP produced precision dies quickly so that we could move ahead to other parts for the Sovereign programme and complete the plane on time, and on budget", concluded Stephens.

Further details are available from: Vantico Ltd. E-mail: Renshape.europe@vantico.com; Web site: www.vantico.com