getting aluminum for thermite?

OK so I know you can get aluminum from an etch a sceh, or you can grind up a chunk of aluminum. i dont have an etch a sceh or a chunck of aluminum handy so, I was wondering if I could use chaff from a B-52 it is very fine aluminum. is almost looks like shiney hair but its aluminum... could I use that effectively or is it too thin, its like aluminum hair?