A shipping container transportable multihull

i thought it was over,,,,a month ago,,and things were left alone,,until,,,,and now,,,well i guess if your gonna mess with people,,least EVERYONE should know,,and its not "the points",,its the ABUSE of it. i even read his last couple updates,,without comment,,,until the "kid stuff" AGAIN.,,but i figure if he really must feel like he's a man by messing with me,,he can,,,,least he's leaving everyone else alone hehe
and Thanks for your concerns Chris,,,but trust me,,,,its over hehe

 

I can't GIVE you what you already earned all on your own. Confirming that adolescent "rep points" are your measure of worth on this board, well, hehe, ENOUGH SAID.

 

hehe,,

 

And now, the two of you have proven beyond a shadow of a doubt that the thread makes no sense to me. I'm out

 

Its clear to me now that your self contradictions about your having no desire to further conflict leaves me and anyone who has followed your rants and dodges only leaves me to conclude you have a mental disorder. I can only speculate as to why it manifests itself on this board, but you have my sympathies.

All the best,
BobG3723

 

A cutter rig with an unfurling headsail for running downwind. Supposed to be self steering according to the literature. I might want retractable T-foils and a warp or drouge for some peace of mind.

Anyway, a book arrived today. Fundamentals of Structural Anaylysis, by K. Leet and C. Uang. Over 700 page textbook on engineeering beams, columns, cable tensioned structures and the like. I'm both excited and full of trepidation. Synthetic division of polynomials and a taste of graphing functions was about it for me before dropping out of college. But I'm a little more motivated these days. I need to know (the book is actually pleasant reading) and calculate (dogh!)the forces involved, so I have a question for anyone who's familiar with beam analysis. Are catamaran crossbeams indeterminate or simply supported? Is that the right question? My first guess is that it's simply supported, but how does one take into account the torque moments of the beam to hull connections of a racked catamaran?

Thanks in advance,
Bob

 

Think out of that box bobg, set your "wing-on-wing" from the bow of each hull, then it all makes sense, and has been effectively demonstrated....

 

Ah...the biplane rig. Unstayed or stayed w/ a spar between the mastheads?
I prefer stayed myself, with less mass overhead that goes along with using shroudes and stays for a mast of smaller diameter. I prefer not to interrupt the volume of the cabin with an unstayed mast. Not enough meat in the crossbeam girders for an unstayed biplane rig, methinks, if I'm to make the the crossbeam that work it'll be comparably heavier. Hey you know, a biplane rig of the stayed type works great on crossbeams. I seen a picture of that somewhere.

 

If your cat has a center pod, then this trailer sailor beauty From K-Designs exemplifies the biplane in hull layout.

Still looking for the stayed biplane in crossbeam style.

 

The interior cabin layout of my tacking Nadrua. Compact, like a pickup bed camper, only narrower. A 4 foot narrow canoe with a pole from keel to roof down the center is kind of "congested" inside, IMO. There are some out there, but I haven't seen any layouts. I think Thomas Firth Jones (God rest his soul) had a mainsail and foresail in both hull of one of his cats.

The beam analysis needs my comprehension at any rate. Hmm... will this take me one or two semesters of textbook study.

 

Sorry, but mine is different at 24ft plus beam and 40 ft loa... and hitch -hiker rig (as per John Hitch "X-IT" and others....)

 

Hi Masalai,
Well, I'm sure to a certain degree the Hitchin's rig is in an ideal setup. I only know of it from comments describing it's operating parameters here on this board. For the purposes of this thread, it really boils down to a combination of the sailplans advantages relative to other considerations, hull displacement under 6000 lbs, and form appropriate for the design goals. An open bridgedeck and demountable hulls with the top design goal to squeeze into shipping container does have it's niche that does not overlap with that of a condo cat. Not that we all wouldn't want a palacial yacht, price being no object.

Cheers,
Bob

 

Here's a higher displacement biplane rig cat looks like it "may" fit in one shipping container, demounted.

 

I have read some disturbing reports of a biplanes performance in high winds. Unable to tack or gybe if I remember rightly, a Radical Bay 8000 (boat above) as well. I will see if I can find the report/post.

 

Ahoy there Meanz,
You know, I have heard reports that the possibility for the windward rig to blanket the leeward rig under certain points of sail and apparent wind might be the case. That would proly be the case with smaller sail areas to hull displacement ratios. In T. F. Jones book "Multihull Voyaging", he abandoned his two 26 foot masts after only two seasons due to "poor performance". In its favor, though, he also said they pointed high, were faster than a sloop under "working sails" whatever that means, tacked like a champ, and its low CE make reefing less frequent. But his catamaran couldn't keep up with monohulls of it's length racing against the fleet upwind.

He also surmised that the blade proportions on his cat were proly wrong. Now I've heard how rigs and hullforms have to taken into account together as a system. Different courses for horses. Which makes the accounts of biplane rigs a hit or miss depending on how well its worked in a system. I'll see if I can find this French stayed biplane rigged cat that I believe set a course record. And it is a monster. So maybe if everything from the tip of the rudder to the tip of the mastehead were optimized, you could very well see its strengths. A horse for a very specialized course, indeed.

Cheers,
Bob