Can You Help Me For My Science Fair(2 questions, one thread)

I need to edit a car to test spoilers, I want to keep this short. I am using sketchup to edit the car.
Attachment 4017 This was a curved surface so I opened it and need to connect it to make it a flat surface, unfortunalty when it does register as a face even when I click on the edges or use the make face plugin, if you want to help me edit it, email me at GenZod23@gmail.com because the file is too big to post here.

But the other problem is that it is hollow from the inside, Im using a Makerbot Replicator 2 and I used makerware to test a hollow cube and a filled in cube of the same size and it said it would take the same amount of filiament, so does that mean I need to make a cupholder kind of thing on the car?

Thanks and please respond, this is a time sensitive issue...I kinda screwed up trying to hard.

It looks like you imported the car file from somewhere else, an STL maybe? If so, the STL imports I've dealt with end up with a buttload of extra geometry you don't need. First off, isolate the part you want to manipulate.......


Hmmm.... the more I read your post the more confused I get. I'm not sure what you're asking, what are you trying to edit specifically? Add some more pics and more detail, Either you skipped a bunch of stuff, or I've confused myself.

Sorry about that, I did get this off the internet and it is an STl, but I need to put wholes in the back of the car or at least some kind of slots, unfortunatly the surface of the car is curved and I cannot just put my holes in. I tried erasing the back of the car and reattaching the car, but it doesnt register as faces when I attach all of the lines together, can you help me, Email me at GenZod23@gmail.com for copy of the car please