[Gdeaver]

I couldn't help noticing the poster's location and closeness to a certain aerospace company that begins with a B. If those mid temp prepegs came from there then they are probably of a grade and quality that are not available to all teams in small quantities. I doubt that you could justify the cost and availability with last years rules. Remember the prepegs are shipped refrigerated next day delivery from the manufacturer. The shipping costs almost guarantee the cost is over the rule limit. Another thing about aerospace prepegs that you should be aware of is that there may be additives in the prepeg that are very toxic in the uncured state. These can be added to modify the surface tension of the resin or increase the fire rating of the material. You need to get info on what you have. Lay up today and loose your kidneys or liver next month. Now I'm not saying first teams should not use composites. Just stay away from the super stuff. Our team has used normal dry cloth and room temperature cure epoxy on our robot for years. Every team should put some fiber in their robot diet. As for core material, You can get AL and arimid honey comb material. Not cheap. If you want a flat board for your electronics or for the bottom of the robot, Try some Baltic birch plywood. This year our team will probably use a piece of 6 MM Baltic birch with a layer of S2 fiberglass laminated on both sides. It will stiffen our frame and give us something to mount electronics and other components to. Also don't forget the fiberglass pultrusions. They come in many structural shapes and are available from McMaster Carr.