What is a composite (i.e. Carbon fiber)?

There's a lot of weird thoughts about what a composite is. The most commonly know composite is Carbon Fiber and it has a whole ton of weird thoughts and expectations from people. Not only that, but people who have tried to make a composite may get dwarfed by all the new things and materials they have to use. Yet, all in all, composite construction is actually a very easy task anyone can do, albeit time consuming.

So lets start with a composite:
http://en.wikipedia.org/wiki/Composite_material
wow, look, done! This article is actually pretty good but leaves a bit to be desired when put to practical use. So for now I'll give a brief overview.

A composite is essentially just a fibrous material in sheets that are laid over each other in some sort of pattern. Ply wood is probably the oldest and a very good composite. If you look at its side you can tell its a composite because you can see the layers of wood inside laid so that the fibers of the wood are all perpendicular to each other ( or as close a 90 angle as possible). The strength of composite materials lies largely in these patterns and how the fibers are bonded together to make a solid piece.

Now I'll make a much more detailed post later (since I like pictures) of how this is achieved.

So lets talk about some basic composites:

Plywood(PW): a good start that many people are familiar with. Its strong, light for its strength compared to other solid woods, and in this case, pretty cheap. its made from thin sheets of wood that are then placed so the fibers criss-cross. now a note: all these fibers are grouped in planes (one sheet has all fibers in one direction) which is quite different from other composites.

Fiberglass(FG): this is another nice composite. Its cheap and lightweight so you can quickly build up a nice strong piece. It is weaker than many composites, but a good epoxy (more on that later) will make it many times a good solid choice. It is made of tiny fiberglass strands woven together much like a piece of fabric. The only difference is that each weave is composed of large "bundles" of strands. there are many, many other ways of weaving fiberglass for its many different purposes. Its easy to mold in many cases and can be used for tons of fun things. I recommend it as long as you aren't demanding high strength.

basic fiberglass can be seen to the Left.


Carbon Fiber (CF): The crazy one. This is for basic carbon fiber as there are enough variations to make you go nuts. http://compositeenvisions.com/. look at this, so many freaking weird cloths and uses. Now, there is a whole way to make it look sexy like that (and most people can't tell its CF when it isn't shiny), but I will start with the basics. So for starts, this is almost exactly like FG in its from, but the main difference is that the strands are now Carbon instead of some silicate (glass). This allows for a much better strength-to-weight ratio over fiberglass.

Now notice, fiberglass per volume is lighter than CF, but is weaker per volume than CF so much so that for the same strength, less mass of Cf can be used. Yet it will still probably cost more.


The site I showed you looks a bit expensive but not too bad, but just remember to look at how much you are buying.

Now, next time I'll go into the many types of weaves and how crazy they are.