Lessons learned and more pics...
far left is a test article, really fast
It has a simple styro flat-bottom hull, during testing ran both with and without a rudder... and has a "Help Wanted" thin plastic sheet material used for a sail.
It ran faster with a rudder for my son, for me I liked the "no rudder" weight savings.
This little simple boat taught us weight is KING. It ran a 5' gutter over 2s faster than our (far right) Balsa and hot-glue boat with same type of sail (and thick plastic rudder).
Just for giggles I puffed HARD at the test boat (far left) and it would wreck at least half the time (no straw used, BTW)... but a couple of times it jumped (and I mean jumped!) to the other end of our 5' gutter in (we're guessing) about .5s!!!!
It is SOOOO light!
Weight is king!
The middle boat:
This is our new Black Pearl.
Thin plastic "Help Wanted" sign is the rudder, styro body (currently still unsanded, cut on a bandsaw)... sail is a print on standard weight printer paper (the Jolly Roger) with Acrylic overcoat for waterproofing (water based, applied to both sides).
We have a test article painted with Latex (water based) in the garage to see if the paint is compatible with styro (solvents are NOT!)... so far so good.. but the weight... these simple boats are so light, even paint adds significant weight to them... we are debating leaving the new Pearl as you see her...
(she is glued with Elmers, so we gotta at least apply some Acrylic clearcoat)
Note the new Pearl still has a paperclip on her sail just to hold it until the glue dries... and pieces of toothpicks in her sides to also hold the sail (as the glue dries)... these will be removed and the sail unfurled.
BTW, the pics are poorly lit (sorry)... the black painted original Pearl (the Pearl Heavy, hahahah!) is actually a catamaran, not a flat bottom... very small (1/8th or less) separation of her pontoons... too bad it doesn't show in the pics)
The other boats are true flat-bottoms.
All of the hydroplane if you hit the right with the air stream.
http://i5.photobucket.com/albums/y159/T ... esigns.jpg
http://i5.photobucket.com/albums/y159/T ... signs2.jpg
http://i5.photobucket.com/albums/y159/T ... signs3.jpg
http://i5.photobucket.com/albums/y159/T ... signs4.jpg