: Here is a material question for you boat and paddle builders. Which
: material will be stiffer and lighter on its own and when
: reinforced with glass or carbon on both sides you say? Marine
: plywood ¼” thick by 4” wide by 8 feet long or a plank of
: pine wood of comparable dimensions?

: I'm posting this question on some of the boat building forums too,
: so if you see it there too feel free to reply wherever.

: How about balsa wood or other lightweight “core”? I know
: material like that will be lighter and more fragile when on its
: own compared to wood or plywood. But when reinforced to the same
: strength as the plywood or wood will it be lighter and stiffer?

: In a summary, what will be the stiffest, lightest, and strongest
: DIY layup that will not break the bank? I already have some
: carbon cloth and fiberglass tape that I could use to reinforce
: the plank with. I am also considering adding some Kevlar so that
: I can avoid catastrophic failure if the thing breaks. I can
: vacuum bag that whole thing too.

: As a background, I will use this as a stringer for internal
: reinforcement of a lightweight Greenland style paddle. I plan to
: have reinforcements placed at 90 degree angle to it so that
: stringer will not be the only thing inside but that does not
: matter for the question above. More FYI - in addition to this
: “skeleton” the paddle will have external composite shell
: (made from carbon or fiberglass or carbon/Kevlar sleeve) and
: foam to fill the void and provide shape for the shell while
: curing. I know others who have done similar paddles and were
: happy with the results, just curious if I could improve on the
: plywood for the stringer they used without going into much more
: expense.

: What would be a good thickness for the board? Would ¼”
: sandwiched b/w 2 layers of carbon on each side be weaker and
: more flexible than a sandwich of two 1/8” planks with three
: layers of carbon?

: I am pretty sure a core b/w layers of fabric will be stiffer than
: three layers of fabric without a core but if someone has a
: different opinion, please share -;)

Extreme stiffness in a paddle isn't necessarily a good thing. I much prefer a bit of bend in my paddles in use, flexing a bit feels better than one that doesn't.

Bill H.