Catamarans

Just new to the world of Footies (so far designed and built a freesailing one which will get her first outing on Saturday, but I was trying to see anything in the rules to stop one building a narrow catamaran? So long as it was only 6" wide, it would fit in the box?

Rupert,

Go for it! perfectly Ok Perhaps 2 batteries in each hull? Would you think of one keel (fin) or two?

It has been established that only one rudder is permitted, so this might make the conventional one rudder per hull non-legal, but there is no limit to the size of the rudder - unless it pokes out of the back.

The design cycle goes :
[ol]
[li]Imagine
[/li][li]Build
[/li][li]Post pictures here
[/li][li]Bask in the admiration
[/li][li]Go to 1
[/li][/ol]

andrew

Someone built one of those that got to the testing phase. Not to discourage you, but it sank… twice. There may have been another one but I’d have to search the archives.

Come Sir, the need to calculate (or even make a decent guess at) displacement is not limited to catamarans.

AndrewH: Just where in the rules is it stated that only ONE rudder is allowed? I looked pretty carefully while deciding upon the design of my hybrid-scow-catamaran-trimaran. Not completed yet!
Rod

Rupert

Don’t be for a moment discouraged - I know a man who had two different boats sink in the same regatta - he is still offensively cheerful:D

You need very much less volume than a monohull, since stability comes from width, not beam.

You could study at my feet (not necessarily reccommended) and use a hydrophilic joiner between the hulls so they are 6 inches wide WHEN DRY.

andrew

I’d amend that list just slightly.

The design cycle goes :
[ol]
[li]Imagine[/li][li]Build [/li][li]SAIL![/li][li]Post pictures here[/li][li]Bask in the admiration[/li][li]Go to 1[/li][/ol]

That’s my project plan…but I’m going to spin it 90 degrees, and make a 1 ft wide trimaran.
This should keep me off the couch at night until my package from Brett arrives.
(Might even lead to some cool action/pitchpole photos too!)

As far as my rig experiment went, no photos yet, but plenty of witnesses to attest that
it worked okay (on stbd tack at least). I’ll try to get some uploaded over the weekend though.

Thank you Thank you. I just worked out how to make my (almost) 12" x 12" footy tri work…maybe.

Rupert, there was a thread here some time ago regarding what was called the FOOTY cubed rule.
This was a box rule with 12 inch by 12 inch by 12 inch dimensions.
It was to enable multihulls of various types to be built within the FOOTY rule.
Nothing seemed to come of it except for some spirited debate and some great ideas.
I had been working on some ideas previously and continue to have thoughts and schemes.:stuck_out_tongue:
Unfortunately I am mostly a dreamer with many unfinished projects as something new takes my fancy.
I am my own worst enemy but I know that. :devil3:
I am happy to show you some of the things I have been working on to provide you with inspiration and different takes on similar challenges.
Keep going with your thoughts and dreams as only with the input of innovators such as you will the art progress.

What you see here is a catamaran to the standard FOOTY rule of six inches wide maximum, made from swimming pool flotation noodles.
It has a rudder as part of the fin and also has a lightweight bulb which is a lead filled piece of Bantock groovy mast section which can be slid along the fin to adjust the fore and aft trim.
It has undergone trials fitted with a McCormack rig and will work eventually, maybe with a little more weight added.

The trimaran is made to the FOOTY x 3 rule and carved from surfboard foam.
Just FOOTY hulls I had sitting around the workshop with some carbon tubes cut to 1 foot / 305mm width to get a look at what could be possible.
Then came my next project…:lol:

I’ve been building toy boats since I was 4, and I can see I have now come to the right place! Building them as big as 1 foot long is a challenge, but it is nice to see that my ideas are not as far out of mainstream as some others here!
Boat building college must have forced my mind into narrow channels all those years ago…

Catamarans are a very interesting subject. The 6" width restriction makes them impractical. Turning them sideways in the box, to get a 12" width, is also impractical because the 6" length will have it submarining. However, there is one more possibility.

Turn the box on its side!!

This will allow a 12" length, and a 12" width. However, there is no place for the mast to extend, except out the side (formerly the top). You will need to make a mast that sticks out the side of the box, then makes a right angle turn upwards. You will need to further offset the mast by the length of the boom, to allow the boom to swing without getting into the restricted area. Since a catamaran will stay fairly level, this might actually work. But will it be faster than a conventional hull? At best, it will weigh half as much if there is no bulb. Its sail area will still be limited by submarining, so you can’t make the hulls too narrow. Without a bulb, it might turn turtle and be lost forever. But it might be fun to work out the details and try it. I have looked a the class rules, and this appears to be allowable.

Rod,
I found the one rudder rule listed under “clarifications”. http://footy.rcsailing.net/clarifications/pre2007.php

To ‘Someguy’
Thank you for the clarification on double rudders. I had not spotted that one. Oh, well, back to the drawing board! Actually, it makes the design a little less complicated, as an elaborate set of linkages aren’t required for a single rudder, and also allows the rudder to extend for 2" through the stern slot in the ‘box’.
I do, however, hope that putting the batteries in the bottom of the central ‘hull’ of the ‘trimaranic scow’ is not yet on the ‘no fly’ list.

I just realized that the proposed catamaran will have a very large turning moment from the sails being off center. So it may also be impractical.

Has anyone put the batteries in the bottom of the keel instead of lead yet?

Not to seem like a wet blanket but Rule C.2 stipulates that the batteries must be placed within the hull.

It was just a passing fancy!

I liked the idea of shifting the batteries athwartship similar to “rail meat” on a full sized boat but alas that’s illegal too.

To Rupert,
You asked about batteries in the keel— see in thread ‘Footy design restrictions’ 11 April 2008, under ‘Scow’, by Rod. Yes, and it (“Da’s Boot”) sails, but not well enough because the hull was too fat, but the batteries are in the keel, but are inserted and removed through the deck hatch of the hull. It all depends on the meaning of the words “within the Hull”.
Rod

Walt,
My understanding is that the rig can only extend above the box(once outside it)…hence your suggestion on how to rig the cat or tri would seem against the rules.