I got a roll of duck tape taken off me as it could be used to restrain someone, so you'd be surprised what isn't allowed in the cabin. It's not worth taking a chance with the opinion of a security guard who isn't very well paid and is worried about losing his job if he lets something through that may be doubtful.
All kinds of stuff can go in the hold as you can't get to it inflight, BUT some airports such as Manila screen all bags prior to entering the terminal and won't allow knives even in check in luggage.