[zcw100]

You can get started with some rubber bands and soda straws. You just need a lot of patience. That will get you started but there are a limited number of things you can do with that and the rubber bands won't last being under constant tension and will eventually break. It takes a surprisingly small amount of materials, just something for the struts like dowels and some string. The most difficult thing is choosing how to attach the strings to the rods. It takes a lot of adjustment to get the pretensioning correct so you need something that you can change until you get it where you want it.