Search found 185 matches

by Amati
07 Jan 2016, 16:57
Forum: Designing
Topic: design a beach / lagoon proa
Replies: 101
Views: 16070

Re: design a beach / lagoon proa

Rob "keep it simple and enjoy", yes, and perhaps the most extreme solutions are only efficient in narrow bands of operating conditions. re the chop and planing hulls: even on the narrow lagoon that i described the chop is quite steep and close spaced " water like concrete building blocks". If i men...
by Amati
07 Jan 2016, 03:50
Forum: Designing
Topic: design a beach / lagoon proa
Replies: 101
Views: 16070

Re: design a beach / lagoon proa

My personal best on an AHD shorty, flat bottom, vertical sides down at the Gorge. 36 K. Water was like concrete, waves like 3 D concrete, have to use your legs like dampers, and God help you if you fall over forwards. Hitting the sail was better than hitting the water. Breaking a fin was, er, bracin...
by Amati
06 Jan 2016, 17:34
Forum: Designing
Topic: design a beach / lagoon proa
Replies: 101
Views: 16070

Re: design a beach / lagoon proa

And how far do you need to sit out? Windsurfers aren't that levered out. I did some quick and dirty experiments with my universal weight machine Lat bar, using weights to balance out my weight so I was hanging from it like a windsurfing boom, while I had my feet on a scale, and hanging from the bar ...
by Amati
06 Jan 2016, 17:23
Forum: Designing
Topic: design a beach / lagoon proa
Replies: 101
Views: 16070

Re: design a beach / lagoon proa

So to launch a last volley, if you do kind of a half assed order of magnitude gedanken experiment, A windsurfer long board (say 13.5') is ~40 lbs, with ~200 liters floatation A sail anywhere from 60 - 90 sq ft, 10-15 lbs Mast and boom 20lbs A couple of foils ~ 10lbs? So if you added one kayak or can...
by Amati
06 Jan 2016, 17:08
Forum: Designing
Topic: design a beach / lagoon proa
Replies: 101
Views: 16070

Re: design a beach / lagoon proa

At some point, you reach the grey area between a sit on boat and and a windsurfer, which really comes down to steering. Pintles and gugeons (sp?). Seem like a an obvious direction- cheap, strong, simple....But how to attach them? If they both steer, you need 3 hands. How much has been done with ste...
by Amati
05 Jan 2016, 18:31
Forum: Designing
Topic: design a beach / lagoon proa
Replies: 101
Views: 16070

Re: design a beach / lagoon proa

For example,
image.jpeg
image.jpeg (60.96 KiB) Viewed 1558 times
Stick an arm on it with a Bruce foil on the end of it, sit on the arm somewhere, imagine symmetrical hull, etc etc
by Amati
05 Jan 2016, 18:27
Forum: Designing
Topic: design a beach / lagoon proa
Replies: 101
Views: 16070

Re: design a beach / lagoon proa

At some point, you reach the grey area between a sit on boat and and a windsurfer, which really comes down to steering. Pintles and gugeons (sp?). Seem like a an obvious direction- cheap, strong, simple....But how to attach them? If they both steer, you need 3 hands. How much has been done with stee...
by Amati
30 Dec 2015, 16:10
Forum: Designing
Topic: design a beach / lagoon proa
Replies: 101
Views: 16070

Re: design a beach / lagoon proa

Something like this might work, only cut out your own parts? Install a deck or thwarts.

http://www.unclejohns.com/boat/

Also known as the 6 hour boat. Easy to google.....
by Amati
24 Dec 2015, 02:13
Forum: Proa Tech
Topic: Air bubble drag reduction for hulls.
Replies: 23
Views: 4120

Re: Air bubble drag reduction for hulls.

Another way to go might be a flexible hull athwartships- flat in the light stuff, and then water pressure forces the hull into a concave. I've chickened out on this so far. But given the rule cheat I have been crowned with by the IC crowd, it must be worth looking at. If my Gougeon 1:12 models are w...