Trying to design my own cat.

Hi Richard. No the other one Did you go sailing ?

 

"Oh Richard...when will it ever end?" - - - When your wife says, "it WILL end", it will END.... - - the voice of experience....

 

Not yet, Fanie. I'm doing some singing at the moment...doing the final touches on my album.

 

Waterworld was AMAZING.. vertical axis wind-mill, genius!

 

EE01, That has been around for ages..... Where you been hiding - that you have not been aware of that? Have a look here? http://www.boatdesign.net/forums/showthread.php?p=215840#post215840

 

We could proof-read I mean proof listen to your music for you. In about... 470 posts we may get you to do it right

What do you sing anyway ? Me, I don't sing, I have enough enemies as it is, and if the wife sings I go out in the garden so the neighbours won't think I beat her

 

Fanie, I guess my music might fall into the 'pop rock' category. It has an atmospheric sound....might sound a bit too 'distant' for your typical top 40 radio station, but I hope enough people like it, so I can make a living from it.
I'll put a link in here when I am ready to give away a free song...or maybe half a song so you get really pissed off and are forced to buy it

 

Awwww, Richard, post a whole song just for BD.net. - - - - You never know, it may be the biggest and best marketing ploy you ever make and there will be lots of us who will be able to appreciate your style.... This place rocks - so needs a theme song..... Plleeaaasssseeeee

 

LOL. Yeah, you're probably right, Mas. Don't want to leave my potential customers feeling annoyed.

 

Gary Baigent suggests that a finer bow and a fatter stern will help with waves and pitching. I have done another doodle....so I can decide later whether I will use his hull shape or mine.

I kept the double-ended canoe shape but gave it a finer bow and made it slightly fatter aft. An asymmetrical shape is proven to be faster for modern human-powered canoes. Don't know if the principles would benefit my catamaran.

I have no idea whether it would reduce pitching significantly. Just thought I would draw it and show it.

Keeping it double-ended means I can use it like a party pontoon in a safe environment, without the transom dragging like a brick.

It has no rocker, so the buoyancy is more evenly dispersed, which should help with pitching. Unless someone can give me a reason why no rocker is a bad thing (apart from slower tacking), then it seems to me that no rocker is a good thing for a boat that is designed for slow speed.

I want the deck layout to stay as it is, regardless of what hull form I choose. The cabin houses make the boat feel more fun and interesting....worth the extra windage. The aft tramp will span the entire BOA.....the decks will be recessed below the tramp.

If I can decide on the hull shape, then everything I wanted to conclude will be concluded. I'm ready to put this thing to rest and hand it over to a NA. Getting some more sailing experience will be good, but it won't teach me enough about design problems like this.

A question to all the experts in this forum (including Gary):
Even with the aft buoyancy and no rocker....will these canoe hulls still give me a problem with pitching? If so, then Gary's way wins. Is it worth comparing hulls in a VPP?

 

no rocker

Richard le artiste musique,
You have fined up the bows and put more buoyancy aft which is an improvement- but you have put the accommodation well forward where the buoyancy is less - wrong way mate. That will definitely (if there is the usual accommodation weight placed forward) make the bows pitch into wave troughs and your flat rocker is not going to help you in this situation. Better accommodation aft. Flat rocker gives railroad straight tracking and higher speed - but makes for slow directional changing - slow to tack. And why are you persisting with asymmetric hulls? If you want hull beam, spread the hulls symmetrically, looks better IMO - and way easier to build.

 

Hi Gary, thanks for the reply.

I always intended the forward accomodation to be as light as possible. It's main function is for girls to go to the toilet. People won't sleep there until the boat is moored or beached.
All the main storage will be under the aft tramp....the cabins will be virtually empty. Having them forward but low, makes the boat feel less 'naked' without interfering with the 'close to the water' feeling you get on a small beach cat. I've been through many design options in my 'walk-through' architecture software....and this deck layout just 'feels good'.

Don't care about tacking performance....more interested in lazy sailing.

I agree that symmetric looks better, but I wanted to get the underwater hulls as far apart as possible, while keeping within the trailer restriction in CA. The boat needs as much stability as it can get. I don't care if it's harder to build.

What do you think?

 

Hi Richard, I have a problem listening to your rock song 'minicat_asymmetrical.fbm' you uploaded. What format is it in ?

 

Fanie, when you finish the sea-mansion, and put it in the water, just turn it around a little so that the bows touch New Zealand and I will put a CD in the anchor room.
How is that going anyway? Still buying parts?

 

Hey Richard, I may make the trip to NZ just to get that CD for free since nothing else is for free Bloody hell, now I've got to add an anchor room too.

Going too slow. I'm not very patient, if I want to do something I want to start and get it over with. Much to sort out yet. So, if you will be patient I will be too

How's the voice keeping up ? You singin about the new boat too ?