Mr. Barrett,
tell us about those rudderheads, if you please.

A lot of "little" changes in Draft #5.

1)The section of maximum width was moved from being centered under the mast to being entirely ahead of the mast. The reason being to give a better foil shape to the entire hull, and to gain more leverage against the rig.

2)The daggerboard has been moved forwards 6". This puts it around 1/3 aft of the mainsail luff.

3)The mast rake has been drawn in. I set it so the sidestays go almost vertically from the chainplates to the mast hound (which is set 2/3 up the mast)

4)The deck drops 6" after the rear beam. This allows the rudders to be mounted lower and allows the aft rocker to be lessened to 6" from the previous 12".

5) The fore rocker is still only 3", but it now ends 5' from the bows instead of 6'



I might move the fore rocker back to the 6' mark, I'm not sure I like it as much in this draft as in the previous one.

I drew the boat on an oversized grid to help you all get a feel for the dimensions, and actually managed to get a pretty level picture of it this time.

Darryl's rudder design looks amazingly similar to the G-Cat system. If my original G-Cat rudder housings hadn't been destroyed, I would still be running them and loving every second of it. It's a great, simple, and very effective design.

I have designed and used many different styles of rudder stocks, rudder head shapes, and rudder lock downs, over the years, and these are as simple as I could make in our work shop using nylon turned down and shaped for most of the components with a threaded both ends, stainless steel rod as the "pull up/ push down". It was simple, works faultlessly, is strong, and most of all it is easily and quickly manufactured in house on a good cost basis.

As far as the actual "rudder head" is concerned, they are shaped with a small protruding "crane" facing aft to give the correct leverage and arc to the rudder swing in the stocks.

as previously asked in the other thread, what do you expect your F14 to be sold for darryl?

Hi Darryl,
Please could you post a pic or 2 of your boat directly on the forum, if I follow your link to the catsailor albums I get hung up for half an hour, and then see a white screen, which is not much to go by.

Cheers
Steve

well,
i must have meant rudder stock when i wrote rudder head. if they were on a hobie they would be castings. what is the black material that is on the sides? If you sold them or the plans for the stocks, how much would they be?
i dream of building a mini version of that giant cat with the seaplane hulls and 2 masts. Although the hulls of the mini may not be the seaplane type hulls, the rigs and beams i like.
cheers

I have tried repeatenly to post pictures direct onto the forum steve, but I have given it up as a "black art" that I can't seem to crack the code of.
The rudder stocks, as almost ever other part of the cat, are 100% carbon fibre (except where we have used Kevlar as well) We make the stocks from moulds that I have made in the work shop. We would sell any part of the cat as individual items to any one who was interested in them, but it is still a little premature for us to have worked out the price structure for individual items, our main concern at present is to fully test the cat as a whole over the next few months so that we are confident in it's performance as well as the structural integrity of ALL the componentry before any of it is "put onto the marketplace" besides things like rudder stocks for one cat are not necessarily suitable (due to the differences in transoms) for all other cats

Not to sound like a whiney bastard, but could you start a seperate thread regarding the rudder system you've developed? It'll bring more attention to your rudder system and not side-track this thread which is supposed to focus on hull design (though it does seem to have stagnated a bit). I should be putting another draft of the Freestyle 14 up this week. Just more work on the rocker, hoping to get a general "thumbs up" on it so I can get on to developing the cross sections.

Sorry about that but if you read back through the immediate posts, you will see that all that I have done is to respond to direct questions. Still it is your thread and I apologise for conjesting it with other matters, mind you what has been said should be of some interest and advantage to you while working on your own design, like they say "a designer can never have too much imformation"

Darryl, I actually want to hear all about your rudder system- just not in this thread. People who are looking for rudder information will likely skip this thread and the information will be lost to them. For my rudder systems, I've got two sets of Dotan Sampson 25s and two sets of Hobie 14s. Likely I'll make the mounts set for the Hobie 14 system and adjust the Dotans to fit. Then I can run whatever system will hold up better. The Dotans won't hold up at all on my G-Cat 5.7M, but I think the F14 is just the boat for them.

well sir,
i gotta say the rudder system is part of designing a cat, and the title doesn't say only the hull design. didn't mean to side track your thread.
i seek to post a side view of a c class hull which has a fast looking rocker. admittedly cogito has a curvier rocker and was faster around the course. cogito's hulls came out of the paitent lady molds which have got to be over 10 years old. so i recomend that you closely follow existing design.

the attachment seems to have worked. all i did was hit the browse button and navigate to my desktop where the picture resided. the catsailor server seems to host the picture for us once uploaded from our computers.

Mmm, is that a wooden rudder I can see at the stern??