07.10.2021

Behind the scenes: Creating molds and components

When we began this journey, we decided to build tools, molds and components ourselves for the UR-1, which is the first Swiss all-electric race aircraft.

Design, manufacturing process and stress analysis represent only “chapters” of this story. There are many things to tell and one of the most important involves the manufacturing of molds and UR-1 components led by our aircraft technicians.

First steps

Aircraft technicians work side by side with composite experts, mechanical design engineers, and the stress analysis team. Indeed, the role of aircraft technicians is also to connect the requirements of the design project with concrete possibilities we have in manufacturing components, molds and tools for our first Swiss all-electric aircraft.

Aircraft technicians and team members define together the first priorities about the working process in order to find a better compromise between feasibility, timing of the manufacturing process and cost optimization. There is also a lively discussion about the properties of some materials related to their reactivity and flexibility. Therefore, aircraft technicians are complementary to composite materials experts.

After a brainstorming phase, the team begins designing molds and UR-1 components by using a CAD (Computer Aided Design) software.

How we are building our aircraft concretely

When the design process is completed, the stress analysis team begins a testing phase. Then, the manufacturing of molds and components can begin.

To produce them, aircraft technicians use a CNC (Computer Numerical Control) milling router, which is suitable for “soft” materials (milling dimensions 2500mm x 1300mm x 300mm), a conventional milling machine or a lathe. It is possible to create components by using simple procedures and equipment.

By using such tools, we are able to manufacture all our composite molds and aircraft parts we want on-site.

We can mention the wings manufacturing process as an example on how we are building the UR-1. Due to the length of the wing molds, we have divided them with several junctions.

The wing ribs, which are made of various woods because of their structural needs, were all made by a nesting technique with the required fiber orientation and thickness to optimize the yield.

However, if we estimate that it is not useful to manufacture a part or a component, we contact one of our official suppliers or a contractor and we provide them with all the necessary technical details. For example, when we decided to entrust the manufacture of the canopy to a third party supplier, we built a positive mold made out of fiber glass, so that the supplier could prepare our Plexiglas canopy.

On the contrary, we decided to manufacture the swivel system for the aileron with a lathe and a conventional milling machine on-site.

Timing

Thanks to the expertise of all our staff members, it is possible to forecast how long it takes to manufacture a part or a mold. For instance, creating one of the upper wing skin molds, which is divided in three sides, we know it will take about 4 or 5 days. It is necessary to integrate a 3D concept design to prepare blanks, milling finishing surfaces and treatment. To shorten the manufacturing process, all of these steps are made at the same time.

Testing and adjustments

To check the functioning of molds and tools we previously manufactured, we carry out many tests, which are already explained in the article "Behind the scenes: Testing".

Before the final assembly, we test every component in order to understand if there would be something unexpected once it is finished, and we make all the necessary adjustments.

After assembling all the components together, the quality control is the final step in the process which is allowing us to build the first Swiss all-electric race aircraft.