Hi, I am Katja Kramers, technical manager at the Eco-Runner Team Delft and also very involved in the laminating process. This year, after some doubts, we decided to produce the body in the Dreamhall for the second year in a row. Without any previous experience, I am very proud of what we have achieved so far with the lamination team.
In October, the sponsor contract with KVE Composites was extended. They give us advice and materials when we need it. Moreover, we can put our body in their autoclave, an oven where the pressure and temperature can be controlled.
We have chosen to use prepreg for the body. This material consists of carbon fibers impregnated with a resin. The fibers lie in a certain orientation and by laying them symmetrically, we obtain the strongest lay-up for the layers of prepreg.
The prepreg rolls were first cut into handy pieces with a special cutting machine, so that they fit well in our molds. Which shapes we should cut exactly and to what extent, has been determined by our chief structures.
We used honeycomb for the stiffness of the body. This material has been obtained from Luxembourg at Euro-Composites. It is placed in certain spots in the body to acquire more stiffness and to drill holes, for example, for the front and rear suspension of the Eco-Runner. After laying the prepreg and honeycomb in the molds, a vacuum bag was made to push out all the air between the layers of prepreg. Afterwards, the molds were baked in the 12-meter long autoclave at KVE under vacuum and at a maximum temperature of 130 degrees. This way, we have obtained the lightest possible body with enough strength!
Two molds were used for the exterior of the Eco-Runner. The bottom half and upper half were made in these molds. Because it is normally very difficult to let these halves connect perfectly, we have come up with a smart system. An extra overhanging aluminum edge has been placed on the edge of the bottom half of the mold. Prepreg was pasted against this edge, such that in the end the upper half of the body can easily be placed over the bottom half and the two halves can be attached to each other.
Laminating all parts took 3 weeks after a few months of preparation. KVE Composites provided us with certain materials and a lot of advice. In addition, they visited the Dreamhall once and they taught us how to put a large vacuum bag on the molds.
Yersterday we picked up the top half and now all parts of the body of Eco-Runner 9 are complete! Now we’re going to sand everything. Then the halves are attached to each other and finally there is a wrap over that the PR team is designing. Finally, the body of the Eco-Runner 9 is ready and the rest of the parts can be placed in the body!