Gabriel,

Ideally you will steam or laminate your ribs, so there's minimal outward force. More importantly, they're there for lateral stiffness, and usually to hold the skin (like wide cedar strips on a cedar canvas canoe) together.

What are you using for skin--bamboo or woodstrip or fabric?

: Sorry this is basic, I'm building my 1st canoe. From what I have gathered
: they provide rigidity. When a strip of wood is bent it wants to straighten
: out. Is this outward force the critical function?

: I'm debating on using strips of bamboo laminated at 1"-2" by
: .25" by 2-5' for ribs. They provide a good amount of outward pressure
: and are FREE.
: Or buying some oak, hickory, ash, or something.
: Or puting kligicell/divinicell foam core for deck and re-infocing sides with
: more glass.

: Another thought, Do I even need ribs or deck re-inforcement? Can I get by w/
: all glass with out being too heavy?