Today we prepped foam for our undertray. Using 40pcf foam, we shapped a mold blank. This i sthe first time we have used foam for our molds. I made the decision to use foam due to the added complexity of this year’s undertray. After doing research I determined that we needed a high density polyurethane foam board that is at least 30 pcf. We will use the foam to generate a male mold. The inner dimensions of the tray is most crucial so there is no need for a female mold.
After talking to several companies I found B rated foam from coastal enterprises that i was able to source as a donation. We used a B rated foam because it was free and because we will not run our piece in an autoclave there is no safety risk of air pockets bursting. In all we recieved 3 tons of foam to work with.
Based on the model generated from our aero engineer i worked with jim covington from Harbor Sales to piece the parts into workable foam blocks that the 3 axis gantry bot could manage. We originally planned for a 16” ball mill, but could not get the tool made in time. This would have allowed for a near one piece mold. The software we used was artcam. A gui strong cam software.