As others have told you, you do not NEED a boom. That said, a boom does
make life easier. Except when running before the wind, your sail should
form an airfoil, like the top of an airplane's wing. A boomless rig needs a
fairlead for the sheet in the proper place. With a boom, sail shape is
independent of the degree to which you sheet in the sail. (Don't bring it
in closer than the corner of the transom.)

A sailboat of that size probably has some 35 or 40 sq. ft. of sail. An
adequate boom would be about 1" x 1" (wood) with a yoke (jaws ) like an
enlarged sling shot to keep the forward end near the mast. The "tack" of
the sail (bottom forward corner) attaches to the boom and the boom is held
down either by its weight or by a line. Now the sheet can be attached to
any point on the boom and/or the boat and a two part mechanical advantage
will make life easier. Boomless, the point where the sheet attaches to the
boat is critical and you'd need a block on the sail's clew to gain any
advantage. The wood for the boom should have grain that runs for much of
the length before reaching the edge.

The size of the rudder and centerboard will make a big difference to the
boat's handling. It would be nice if you could get the name of the design
or some other indication that would lead to the designer's plans. (Are you
sure it's a centerboard rather than a daggerboard?)

Roger

http://home.earthlink.net/~derbyrm

"Melandre" wrote in message
oups.com...

Newbie question: I was given an old, very small sailboat (just 8' or
9'). The hull was in a poor state but the sail and mast were in good
condition. I cleaned the hull and repainted the boat and it now is
seaworthy. Well, almost seaworthy. The people giving it away told me
that two things were missing and they could no longer find them: the
centerboard and the rudder.

I figured I could probably build these things so I agreed to take the
boat. I have yet to build a basic centerboard and rudder for it but I
also realized that the boat does not have a boom! Is it possible
that, given that it is such a small boat, it may not require one? I
cannot figure out if they simply forgot to give me the boom
(unfortunately I cannot contact them anymore), if they didn't have a
boom anymore or this type of small boat simply doesn't need one...

If it does require one, how difficult would it be to make a simple one
and what material (wood, metal, etc.) would be most appropriate.

Keep in mind that I am not trying to turn this thing into a competition
sailboat. Just want something to float around and have something to
play around with on a windy day (when it is too wavy to waterski behind
my powerboat). Cheers! Andre