Facet Boat

[sharpii2]

Now here's a whacked out idea for some of us would be designers with little or no money.

How about a challenge to design a boat that has absolutely no curves in it.

It would be comprised of all flat surfaces angled together.

How about a length of 61 cm (24 inches) and a displacement of of 4.0 kg.

The heavy weight is to make the challenge, well, challenging. It is easy to make a light boat of crude shape work.

I would put other design limits on it as well:

1.) Draft + Beam must not exceed 45 cm,

2.) Exterior ballast must not exceed 1.0 kg. Exterior Ballast will be counted as any ballast that goes on or in any keels or leeway preventing fins. After all, a real boat must be able to carry real cargo, and

3.) 'Cargo', anything stored anywhere but inside the keel(s) or leeway preventing fins or rudders must be less dense than water.

4.) The number of facets will be limited to 20, including all sides and transoms as well as the bottom. All the facets on all the hulls would be counted, for multi hulls for example. A 'Keel' must be at least as deep as it's widest point to be counted as such. The deck, keel(s), and rudder(s) will not be counted as Facets

Sound interesting?

Or is this just one of my dumb ideas?

Rules:

1.) Length----------------61 cm (24 inches)
2.) Displacement-----------4 kg
3.) Beam + Draft----------45 cm (8.8 lbs)
4.) Max numb. of Facets---20 (including everything except the deck and keel fin) (cross beams, if any, will be counted as part of the deck and will not be counted as facets, nor will ballast struts)
5.) Exterior Ballast---------1.0 kg max.
6.) 'Cargo' to be less dense than water.

[rwatson]

That would be a geodesic hull -

A bit like
http://gaboats.com/

but without the curves.

[Trevlyns]

The simple response ... Why?

[rwatson]

Thats easy Trevs - because you are stuck on a desert island with only 1 metres square bits of plywood to build your escape boat :-)

[sharpii2]

Originally Posted by Trevlyns

The simple response ... Why?

Just to provide a bit of an intellectual challenge.

I even thought of proposing a handicap system that would reward using less than 12 facets (but not punish using up to 20)

I was thinking it would work like this:

Time allowance = ((12/ number of facets used)/10)+1 with no number less than 1 being used.

How would a good boat designer go about this?

How many facets would he/she use?

How would they be positioned and proportioned?

I was thinking that those of us who are interested could post their design ideas for others to review and criticize.

A good way to show how clever we all are

[sharpii2]

Hi, All.

After some serious thought and examination of my previous proposed rules, I decided to make some changes.

I decide to change the former handicap rule from:

((12/(number of facets used))*6 = seconds per minute added

to this:

(20-(number of facets used)) = allowed seconds per minute added

This way an eleven facet boat would be allowed 9 seconds per minute, while a four facet boat would be allowed sixteen.

A four facet boat would be quite crappy and would not be up to completing the course in just 125% of the time a good one would be able to.

The real advantage to this change is that now there would be no absolute limit to the number of facets used. The limit would come as the added facets improved the performance less and less.

I also decide to cut the size of the boats down to 30.5 cm in length. This would give them 1/8th the displacement and make them much easier to cart around.

Below are the revised proposed rules:

R/C FACET BOAT COMPETITION

by

sharpii2


Would be a competition to make R/C sail boats that have absolutely no curves in the hull, but are made up of flat surfaces called facets that are angled to each other to approximate curves as close as possible. These boats would be sailed around an equilateral triangular course

A handicap would be set up to reward using as few facets as possible. The handicap would work as follows:

(20-(number of facets used)) = seconds per minute time allowance.

A boat that had only ten facets would have an allowance of ten seconds added to its time to get around the course.

A.) The dimension limits of these boats would be as follows:

1.) Length---------= 30.50 cm
2.) Beam + Draft* = 22.75 cm
3.) Displacement = 500.00 cc
4.) Ballast keel--= 125.00 gm
5.) Max Keel Vol.= 63.00 cc

Facets forming only the hull would be counted.

B.) The deck would not be counted as long as:

1.) it’s lowest point is at least half the Hull Draft** above the at rest Water Line, and
2.) is sloped or cambered upward up to a no more than 0.25 times its maximum width.

The Deck can have end facets that aren’t counted as well, as long as they do not fill in more than the maximum allowed pitch or camber

C.) The Fixed Keel(s) would not be counted either, provided:

1.) it displaces no more than half its/their weight in total and
2.) weighs no more than 125 gm.

D.) Rudders and un ballasted fins would be allowed providing:

1.) they do not cause the boat to exceed its maximum allowed Beam + Draft limit when fully extended,
2.) weigh no more than 1.50 times the amount of water they displace, and
3.) displace no more than 50 gm total.

E.) Internal Ballast will be allowed as long as:

1.) is placed only in the hull, and
2.) weighs no more than 3.0 times what it displaces.

F.) Multihulls would be allowed provided:

1.) they satisfy Beam + Draft limits,
2.) they satisfy min. displacement, and
3.) all the facets of all the hulls are counted.

G.) R/C channels:

1.) two will be allowed.



*Draft = distance from at rest Waterline to lowest point of Keel, Rudder, or Fin.

**Hull Draft = distance from at rest Waterline to lowest point of hull.

Any comments or suggestions?

Also attached is a drawing of a crude 5 facet boat to help illustrate my proposed rules.