On September 4, 2016, Minghao visited U of T's Blue Sky Solar Car Team. This page documents some key points in their composite process explained by Sean Doughty, their Chief Engineer.

Mounting to composite panels

When they want to mount to composite panels (CF - honeycomb core - CF) using fasteners, they will cut out an area of their core material and replace it with a metal plate. Holes are then drilled through the entire piece after it has cured to achieve the desired mounting points. This is ideally designed as part of the panel itself and implemented during the initial layup of the panel, however they are also able to add an arbitrary mounting point to an existing panel by cutting out one side and removing the core, inserting the metal, and laying up CF over top (weaker than doing it during the initial manufacturing of the panel).

This technique was developed with help from their team alumni after they ran into issues with their suspension ripping out of their car during races. Sean explains that attaching fasteners directly to composite panels with a honeycomb core will crush the panel, compromising its structural integrity.

Unibody structure

The main aerobody for U of T's most recent car was constructed using many separate MDF molds with interior faces soaked in epoxy resin. The external walls of their aerobody are extremely thin (~3 mm) as the majority of the structural strength for their car comes from a composite chassis formed with intersecting composite bulkheads. These bulkheads use thicker honeycomb core material similar to that used for MSXI's monocoque.