Small trailerable cruising cats... biggest flaw?

[rayaldridge]

In my opinion, it's the difficulty of folding them in a way that is as simple and fast as folding small trimarans.

A number of ingenious solutions have been tried. Among the best are Richard Woods' cats that have all accommodation in the center deck, and fold the hulls under that deck for trailering. It's a great solution, especially considering his out-of-the-box solution to ergonomic comfort at anchor-- his drop floor.

My objections to that approach might not matter to lots of folks, but I would prefer a solution that didn't involve tipping the hulls over, and that preserved the open bridge deck, which in very small cats is really nice to have, for a deck tent that can greatly expand the interior at anchor. I'd like to have all accommodations in the hulls, for lower profile and wind resistance, while still retaining sitting headroom below. I'd also like a solution that allowed the boat to be folded on the water, so it could be kept in a narrow slip. Lastly would be a way to fold the cat without having to lower the mast, so that unfolding to sailing beam was a matter of a couple minutes, instead of the hours it generally takes most trailerable cats that fold or demount.

All these problems have long since been solved for trimarans. Cats are a more difficult engineering problem, I think, but I wonder what progress can be made?

[SerjKu]

If to contemplate this problem on an example of projects R. Woods it is possible to tell that Wizard and Sango are easily turned off. But they look not so attractively (UMHO). Merlin, Strider, Skua look much better (UMHO). But for this purpose that they would be convenient in transportation and deployment, extras are necessary.
And it simply catamaran of my acquaintance

P.S. I am sorry for my bad English.

[4sail]

A great looking trailerable catamaran, SerjKu. Do you any information that can be posted?

[rayaldridge]

Yes, I'd be interested in knowing how it folds.

I don't think my list of design goals is unreasonable, but I can't seem to find a design that fulfills that list.

[AnalogKid]

Ray, have you looked at how some of the Wharram owners launch their trailerable-sized Tikis?

The beams are retained in tubular sockets on the deck of each hull. On the trailer, small 'dummy' beams are inserted to keep the hulls upright and together. Once launched, the front and rear beams are replaced with the full-length sailing beams while the centre 'dummy' beam is retained. The full-length beams are lashed at one end while a line with double purchase is used to drag one hull to the far end of the beams. Once the front and rear beams are lashed at both ends, the centre beam is also replaced.

Obviously no deck is in place while all this goes on, the deck boards being sectional and put in place after the boat is 'expanded'. But what if the open deck could be made to concertina down between the hulls in the folded position?

[Steve W]

Analog,what you describe is much the same system that was used on my Macgregor 36,i built a telescoping trailer that allowed it to all happen on the trailer,it is however more of a transportable cat rather than a trailer sailer
Ray, Roger Simpson had a design for a folding cat that used ladder style crossbeams that had some depth and hinged in the middle and at the hulls,i think the center of the aft beam went aft and the mast beam went fwd,the tramp stayed laced to the hulls and there was a solid link bar that connected the beams together in the center.The boat was about 24ft i think. I dont know if the design is still available.
Steve.

[rayaldridge]

Analog-- that was sort of the same system as my old Wharram Tane, except that the old system was a lot less convenient. There were transport beams and sailing beams, and these had to be switched after launch. What made it worse was that there were two forebeams joined by a slat deck, and two aft beams, also with attached deck. Even when I was young and strong that was a pain to manhandle. I had to lash temporary 2X4 beams to the gunwales to keep the hulls from tipping over when they were freed from the transport beams. It took half a day to launch the boat, and it wasn't any fun.

Steve, the Simpson design sounds a bit like something I'm considering. Do you know how the hinges were reinforced to take strain? I'll try to look up the design. Simpson seems to have been sort of an unrecognized and under-regarded pioneer.

[SerjKu]

http://www.catamaran-ivan.ru/
QTU_oT2GK-E
1O9Scnu2_80

[SerjKu]

I the сatamarano-dreamer, but at me "a hole in a pocket".

[CatBuilder]

Here is one as well:

http://www.multihulldesigns.com/designs_other/30tubecatslide.htm

http://www.multihulldesigns.com/images/trail1g.gif

[Steve W]

Ray,The Simpson design im thinking of was called the Takeaway and was designed in partnership with an Alan Dowd,na. The beams are trussed metal and look like they are at least a foot and probably have full height pins,3 per beam.
Steve.

[jamez]

Ray,The Simpson design im thinking of was called the Takeaway and was designed in partnership with an Alan Dowd,na. The beams are trussed metal and look like they are at least a foot and probably have full height pins,3 per beam.
Steve.

I enquired about this design some years ago, was told (by Boatcraft) only one was built at that time (early 2000s iirc). from the study plans i have the hulls are quite roomy, for a 24' cat, and flared so the waterline is relatively narrow - sort of like a scaled down Backslash. The folding mechanism/beams are welded aluminium. You could check with Boatcraft Pacific for plans availability.

[rayaldridge]

Thanks much, guys-- very useful information. Massive-looking weldments on the Simpson-- ought to be plenty strong.

The boat I'm drawing now is intended for simple amateur construction (I'm a simple-minded amateur.) It's 19 feet 8 inches, and should weigh 800 lbs on the trailer. The idea was to come up with a design with more sailing beam than a Jarcat or other small fixed-beam cats, so a recycled beach cat rig would drive it adequately and safely, and a compact car could pull it. I probably need to use a slightly different approach. I'm trying to figure out a variant on the same approach Simpson used, but with wood and epoxy. Also, that approach, at least as shown, doesn't allow you to keep the mast up when folded, unless I'm misunderstanding the pics and drawing. That's a tough nut to crack, especially with the rotating mast I plan to use. But great food for thought. I really appreciate you guys going to the trouble of posting the info-- it definitely helps me.

SerjKu, what a fine-looking cat! I like the central pod for the motor. Looks very fast, but I was impressed at how dry the boat seemed to be, even in that heavy air. Nice!

[AnalogKid]

How about building the folding mechanism strong enough to keep the hulls upright on a mooring, then 'reinforcing' them with additional inverted U-section beams slipped over the top and pinned in place. It would allow the hinges to be built on a more managable scale.

To my mind, the hardest part in this exercise is figuring out how the deck is to be folded or stowed and then replaced when going to and from narrow-beam format.

[Fanie]

You can look at 'cattofold' as well
http://www.cat2fold.com/

One of my designes has the front and rear beam one end each attached on a pivot so that both beams can swing into the length of the boat, but it requires flat-ish hulls.

[Steve W]

Ray, how about using 2 recycled sailboard rigs instead,1 in each hull,as im sure you know k designs uses this tandem rig on some designs and it allows you to keep the rigs up when folded.
Steve.

[Steve W]

Oh,another quick folding system that has been used with some sucess is the solid wingdeck hinged in the middleso the hulls tuck under.Shark cat 20x10 ,Maine Cat 22 x12 and Viva 27 x 14 all use this system. Course the mast has to come down first and you cant use the tandem rig.
Steve.

[rayaldridge]

Steve, that's not a bad idea. I think Bernd Kohler has a little cat that uses two windsurfer rigs. But I have a Nacra 5.2 rig that I hope to use, and no windsurfer rigs.

The problem I see with cats that fold the hulls under, though that can work well, as in some of Richard Woods' designs is that then accommodations must be mostly in a center pod. I want to keep windage down, and it's hard to get sitting headroom in a central pod without making it pretty high. I think this also requires a more elaborate trailer. Thomas Firth Jones designed a small cat that folds in the middle like a Shark. Maybe the worst aspect of this solution, in my personal situation, is that the slip I have available to use is only 10 feet from wall to wall, and folding in that manner means the hulls would be lying on their sides in the slip, collecting crud on the topsides.

Again, I appreciate the thought you and others have given to my problem. I have to say, it's really been stimulating, and helpful-- the thread sat here for a long time before anyone ventured an opinion, so I wondered if maybe my list of design goals was just too silly to be taken seriously. I really think there's a design niche there to be explored, and I wonder why the Simpson design was not more popular. Maybe it's the weight.

[jamez]

I wonder why the Simpson design was not more popular. Maybe it's the weight.

With a cedar strip build, and the extensive aluminium fabrication holding it all together, it would not have been a 'cheap' boat to build, maybe no cheaper than a Trailer Tri 680/720 - just conjecturing here :D Re the mast and folding, if thought was given to designing a suitably strong step, a set of appropriately sized temp bungee stays could be hauled up the spinaker halyard to hold the mast in place during folding.

Folding system aside I think as a cruising design its got a lot going for it. Roomy hulls, nearly 1.8 headroom, a sensible low aspect rig which combined with 4.5 metres beam would give great stability. I thought it would be nice built non-folding ( I keep my boats on a swing mooring) with a single cockpit between the hulls like a Tiki. However the plans were only availble as the folding version so any modifications, like new beams, had to be self engineered. Went in the too hard basket and now I'm building a Tri;)

[Fanie]

No come on Jamez ! Too hard ?

There is going to be a perfectly common not-too-hard solution to make a cat foldable.
It's simply a matter of you have to sit and play with it, it will come. Remember there was a time the tri-guys had the same problem, then when someone comes up with a solution it was like 'of course'.

I was going to play with some ideas, but other things came in the way. Will play some more when there's a gap.

[Steve W]

Ray,dont forget,when a Farrier is folded and kept in a standard marina berth,it would also get barnacles and slime on the topsides of the amas if not antifouled. The Viva has accomodations in the hulls but clearly they cant be used folded. You know,ill bet that you could incorporate a system into the hinge pin of the Takeaway so you could leave the mast up, there is a lot of depth to those ladder beams and if you were to have a decent diameter pin, say 1.5", it could extend up enough to support a tabanacle and be ridgid enough to support the mast with the shrouds disconected temporarily while folding and then rig something for support while folded, lots of details to figure out.
Wait a minute,you are only talking something about 20ft x 10ft so you only need it to reduce about 2 ft to fit your slip or to trailer,that may be easier.
Off topic, i recently picked up a cool beachcat on ebay which i want to use as a beach cruiser.Is an old Pacific cat 19,designed by Carter Pyle in California in 1959 ,mine was built in 1970, they have got to be one of the first fiberglass surfcats but the cool thing is they have cockpit wells for your feet and a solid bridgedeck where i was hoping to be able to pitch a dome tent, it has a beutiful organic looking main crossbeam and real sweeping sheerline like a Newick tri,kind of a big rig though so reefing mods will need to be made. I picked up a 1.2hp x 14lb outboard which tuck neatly into one of the aft lockers,im excited. Paid $305 for it with an almost new Galvernized trailer and my son and i drove a 2700 mile round trip in my old Tdi Passat to get it.
Steve.

[dstgean]

Off topic, i recently picked up a cool beachcat on ebay which i want to use as a beach cruiser.Is an old Pacific cat 19,designed by Carter Pyle in California in 1959 ,mine was built in 1970, they have got to be one of the first fiberglass surfcats but the cool thing is they have cockpit wells for your feet and a solid bridgedeck where i was hoping to be able to pitch a dome tent, it has a beutiful organic looking main crossbeam and real sweeping sheerline like a Newick tri,kind of a big rig though so reefing mods will need to be made. I picked up a 1.2hp x 14lb outboard which tuck neatly into one of the aft lockers,im excited. Paid $305 for it with an almost new Galvernized trailer and my son and i drove a 2700 mile round trip in my old Tdi Passat to get it.
Steve.

Pictures! We need pictures!

Dan

[AnalogKid]

Pictures! We need pictures!

Dan

Seconded.

[rayaldridge]

Analog. I think you're right that the key here is that the hinges don't have to carry the forces involved in sailing-- they only have to carry the forces involved in folding the boat for trailer or slip. Then they can be reinforced for sailing by some sort of mechanism. Thomas Firth Jones got me to thinking down this track. He had the same thought when drawing his folding design Brine Shrimp. In that case, the beams hinge upward along a central line. He uses I-beams in his later designs, so to strengthen his beams, he just bolted a block of I-beam inside the flanges of his main I-beams. That wouldn't work for me, because my hinges open laterally rather than upward, but I think the principle can apply, somehow. I don't mind bolts, because they can be tightened rapidly, if the mechanism is positive enough to make the boltholes line up perfectly. Boats that rely on rig tension to hold folding mechanisms in place, like some small tris, worry me. I can't help but wonder what happens if a stay lets go out on the bounding main.

Jamez, when I was looking at the drawing of the Simpson you posted, I noticed that the trailerable weight was 700 - 800 kilos, and the displacement was 1100 kilos. That struck me as low payload for a cat that size, but I'm really not familiar with what's acceptable. On the 20 footer I'm drawing, I'm hoping for a 600 kilo payload. That's on hulls scaled up from Slider, my 16' beachcruiser.

I think you're on the same track as me when it comes to the mast. I've thought about using the trap wires as temporary back stays.

Fanie, I hope you're right about there being a solution that will seem obvious in retrospect. I think you probably are right.

Steve, I think you've figured out where I'm going with this too. Because I want to step my mast well aft of the forward beam, I'm using a central spine to hinge the beams off of, similar to the Simpson folder, but with the hinges reinforced by bolt-on structures. The central spine does mean that I have to take a few inches from the individual cabin width, but It presents some opportunities, too. I plan to use a single central rudder and board, which means no board intrusion into cabins, and no tiller linkage to have to unship when folding. I'd thought about putting a little outboard in a pod-type well built into the spine, but eventually decide to put the motor on one transom. But anyway, it means that the boat can be motored and steered when folded.. I'm actually going to see if I can work out a 12 foot beam for my 20 foot cat. That gives a lot more deck space on the central deck, which is the nicest place on a boat that size. With a boom tent, you have a lot of real estate under cover. The Nacra rig has a fixed gooseneck, so I'll have to do something about that to have a boom tent with standing headroom, as I do on Slider.

You've really got a piece of history there. It's funny that folks will spend gobs of cash on china figurines or antique chairs, but when it comes to the history of the multihull in the West, the history is being left to rot in backyards, or sold for a pittance on Ebay. I'm envious of you. Got any pictures?

[ThomD]

What ever happened to that New Zealand folding cat everyone was excited about a few years back. It used a kind of playpen system to establish a central tramp was, really cool, then he "ruined" it all with a plan to build an even bigger boat. Never heard any more.

I prefer the idea of fixed decks etc. and the whole G32 thing in this size. What is more no one has provided plans for such a thing to satisfy the evident demand that was there even at 30 thousand plus decades ago. Particularly if it could be simplified. It is tougher than it seems to be due to the fact that the natural displacement for that kind of thing is 200 % of the dry weight, which means some very careful design. The boat you are making can have 100%, a fifty fifty thing. Some of boats that use folded amas are closer to trimarans at 50% of the dry weight.

My 21 with water displacement has reached this point. There will be a cabin, this is just the hulls and decks and pods. Also I got this far, and then sorta thought, that if I just dropped it down to 18ish it would make a very nice Miss Cindy platform and be a lot easier to build. In the drawing it is about 7.5' beam x 21', and could obviously be wider and still be trailered.

[rayaldridge]

Thom, the problem with the G32 was that it tended to capsize pretty easily. To me, that's just not acceptable in a cruising boat.

There's someone in Pensacola trying to sell a modified G32. The beam was widened to 12'. They want 40K or offers, but it looks like a pretty nice boat.

http://pensacola.craigslist.org/boa/2091204392.html

[dstgean]

I think lots of the capsizing issues were that folks that wanted the G32 were also racing them. I read a story fo Mead capsizing one 4x in a race and finishing well. Since I'm planning on going with a reasonably small beam on my Tamanu double cat, I hope prudent reefing will make for a fun and cruisable platform.

If Ray comes up with something clever, we'll all have a chance to give it a whirl since this is something of a holy grail of catamarans.

Dan

[ThomD]

"Thom, the problem with the G32 was that it tended to capsize pretty easily. To me, that's just not acceptable in a cruising boat."

Not true, the G32's problem is that it is outside the box. It's like saying that an F boat is unsafe because the protential exists at some level that someone would put up the sail while the floats are pulled in. It's a very smart design, but when one sees the tape, now on youtube, one can see how the general public might not like all the talk about capsize. It's just a further example of the capsize myth, in which it is apparently impossible to separate racing from crusing. One can dial in whatever amount of of stability one wants. If Slider is safe, there is some degree of canvas to water ballast where G32 is equally safe, probably more safe. Yet Slider doesn't have a high performance potential, and the new boat won't either.

But more important, if you want safety, the G32 format is rightable. But this is the key point. As one shrinks the overall length to 16 feet one reaches a point where the boat is now a jarcat, and still has water ballast and rightability, and also a conventional form factor.

So stability is not the issue, it is really a mater of at what length other than 32 feet is there enough G32ness left to make the complexity worth it. I wouldn't probably bother with it at 16 feet, but it becomes interesting at some point beyond that point. At 24 feet one has a 1-3 form factor which has been used extensively in cats, can hardly be regarded as radically unstable. One probably has the potential for more sail, and lower resistance than the jarcat, and can probably start to justify some of the cost of complexity that is there. Either option, reducing beam, or righting and water ballast has some appeal. A game changing option for folding would be... game changing. Tough though. So far we are at zero for cheap easy to build options of high functionality in any folding form I am aware of. There are advantages to water ballast and righting. The only really complex part is the step. Bad news is that it is mostly a machine shop type of thing. Good news is it won't have the problems of generating parts that are load bearing, folding, and have good marine durability, which is a nightmare in beams. Water ballast is an easy problem. Had a G32 type deal caught on like the Fs, it would have been easy to supply in generic mast step form, unlike the integrated folding beam problem. And the mast step solves the problem of mast raising.

[sabahcat]

Off topic, i recently picked up a cool beachcat on ebay which i want to use as a beach cruiser.Is an old Pacific cat 19,
http://www.thebeachcats.com/classifieds/catamarans/p10860-pacific-cat-19.html
http://www.thebeachcats.com/classifieds/data/1/large/173.JPG

[Steve W]

Thanks Sabah, i was looking for my ebay pictures but cant find them (and wouldnt know how to post the if i did)
A few of the things i like about this cat are the foot wells with hiking straps, i find it tiring with your legs out straight like most small cats and my old Macgregor 36, there is a large 3" drain through the transoms which you can barely see below the bottom rudder fitting. The forward location of the aft beam keeps the crew forward and allows for good sized storage lockers aft for light stuff,ill need to make them watertight though. The forward crossbeam makes for a nice place to attach a fwd net, i used to sail a G cat 5meter that had this feature and i loved laying up there at anchor or in light air. I wish the bridgedeck was flatter though for sleeping on. The daggerboard trunks are in the footwells. That main crossbeam has a very sexy shape when looking from the bow or side view much like a Newick tri,( or the Newick tris look like it)
Ive wanted a beachcat for a while but not just any beachcat, a P cat, but most of them are in California, so when my son saw this one on ebay i jumped at it.
Steve.

[dstgean]

Is that the cat you bought? Sorry, a bit dense here...the one in the catsailor classifieds?

Dan

[rayaldridge]

"Thom, the problem with the G32 was that it tended to capsize pretty easily. To me, that's just not acceptable in a cruising boat."

Not true, the G32's problem is that it is outside the box. It's like saying that an F boat is unsafe because the protential exists at some level that someone would put up the sail while the floats are pulled in. It's a very smart design, but when one sees the tape, now on youtube, one can see how the general public might not like all the talk about capsize. It's just a further example of the capsize myth, in which it is apparently impossible to separate racing from crusing. One can dial in whatever amount of of stability one wants. If Slider is safe, there is some degree of canvas to water ballast where G32 is equally safe, probably more safe. Yet Slider doesn't have a high performance potential, and the new boat won't either.
.

Well, except that the F-boat is not designed to be sailed at trailerable beam and the G32 is. That seems a significant difference to me. One circumstance is a boneheaded mistake that would be fairly hard to make, and the other is SOP.

I'm wounded! Why do you think my new boat won't have a high performance potential? It will weigh only a little more than Slider, and have 220 sq. ft. of sail, compared to Slider's 140. It will have a longer waterline, and be able to carry its canvas in heavy air. It may not be a barn-burner, or as fast as the beach cat the rig came from (except in heavy air, where it should be pretty fast) but it was designed in part as an answer to those little tris that are being built to use donor rigs from beach cats. I'll be disappointed if it isn't fairly fast. (Imagine me sitting here with a sad face.)

Re the G32, with the best will in the world, I can't believe a boat with less of a righting lever than a Hobie cat and such a massive rig is really suitable as a cruiser. It may be possible to sail the boat safely, if one is hyper-alert, and reefs very conservatively, but the nature of cruising is that unexpected things happen. What may be safe on Long Island Sound will probably be a bit anxiety-arousing in a blow out on the ocean. The fact that the boat can be righted does not reassure me. The rig is fragile, and would probably not survive a capsize in a seaway-- in fact, there's a famous story about the boat being taken out for a test sail with a writer from Sail aboard, and losing its rig. Maybe I'm just a Chicken of the Sea, but I wouldn't get out of sight of land in a Gougeon 32. To me, if cruising is not relaxing, it's not really cruising.

The thing about Slider was that she was about the longest boat I thought suitable for fixed trailerable beam, and then only with her very modest rig. Looking at other cats, like the Jarcat, with similar beam but bigger rigs-- you start to see a lot of capsizes. I'm sure a good alert seaman can keep a Jarcat on its feet, but the Gougeon 32 is a whole other order of boat, and is that really what cruisers want? I hate to be relying on this logical chestnut, but a number of the boats were built, at least 14. That strikes me as a fair trial. If the boat were a really good one, that should have been a big enough sample to propel the boat into general acceptance. But they were not very popular and they have a fairly low resale value. There was probably a reason why the owners did not like their boats enough to keep them and use them.

For almost any other sort of boat meant for cruising, there are logs of cruises accomplished. Do any such logs exist for a G32? They've been around for a long time.

To be clear, I'm not saying it's a bad boat, I'll bet it would be a lot of fun to sail. I'm just saying it's not really suitable for cruising.

In the choice between beam and water ballast, I would go for beam every time. I think it's safer and faster and gives more usable deck. The trouble with shifting water ballast from one side to the other is that the process takes some measurable amount of time, and things happen awfully fast sometimes out on the water. Beam is always there, for good or ill. If I remember correctly, the water is removed from the G32 by bailers that depend on speed to function. What happens when the boat is taken aback suddenly-- all that weight will be on the lee side and no way to quickly get rid of it. I'm wondering how they handled tacking in heavy air, with that setup.

[dstgean]

In the choice between beam and water ballast, I would go for beam every time. I think it's safer and faster and gives more usable deck. The trouble with shifting water ballast from one side to the other is that the process takes some measurable amount of time, and things happen awfully fast sometimes out on the water. Beam is always there, for good or ill. If I remember correctly, the water is removed from the G32 by bailers that depend on speed to function. What happens when the boat is taken aback suddenly-- all that weight will be on the lee side and no way to quickly get rid of it. I'm wondering how they handled tacking in heavy air, with that setup.

In short tacking I imagine they just had both ballast tanks filled. I'm with you on the beam thing there even though I'm going to build a 20' double Tamanu hulled cat with a Hobie 18 rig. I feel confident for two reasons: the Tamanu hulls are lighter than the smaller Hobie hulls thus helping righting, deep reefs are possible and should be used for cruising.

As another thought on the narrow beam cat that was tried out west on at least one boat is sponsons. The boat I'm thinking of was actually a bit of a beast as it was a quad hulled thing. I'm thinking of something like a hiking seat on a H21 or H18 but bigger and buoyant like a sponson. It would only work in these 'tweener sized cats, but plugging in a pair of sponson/hiking seats seems pretty quick compared to the elaborate setups of most other folders. Once put together, the wide beam is better in every way. If the wide beam boat is such a hassle to use that it doesn't get used, then the narrow boat with its limitations becomes the better boat in my opinion.

Dan

[oldsailor7]

At one stage in my nefarious multihull career I had a Lock Crowther "International 23" catamaran.
It had oval alloy crossbeams on which the hulls slid in and out. The foam/glass sandwhich deck folded up in the middle when sliding the hulls together. It worked vey well, but as usual the firm making this design went belly up and that was the end of it. Pity as it was a fast little boat and would sleep four in single berths with a toilet in one hull and galley in the other.

[Steve W]

No Dan, mine is blue hulls and decks,not in bad shape though.
Steve.

[Fanie]

Fanie, I hope you're right about there being a solution that will seem obvious in retrospect. I think you probably are right.

Hi Ray,

This is how I plan to make my small(er) cats fold. There is a basic procedure you have to follow but most people can follow a logic few steps. Folding up or open should go quick, probably a minute or two only. You still have access to the hulls and the deck storage spaces. What won't work in the deck storage should go in the hulls.

The model I drawed has hulls 800mm wide and 1200mm high, this is up to you. The deck I drawed to be 350mm deep since most things fit in that depth. The folded hulls is 2m350 wide give or take a few cm, but it can be trailed legally. Height when folded is 2m230 and how long your hulls are is up to you. When folded open the cat is about 4m200 wide. The deck is level with the hulls so you have max deck space, many girls should fit on there.

The only drawback is you cannot fit a single outboard permanently, you will have to make a removable bracket for it, although if you fit two motors, one on each hull then you haven't a problem. Two motors on a cat is way better in any case.

The function of the different beams are only to keep the hulls upright during folding. The support beam has to keep the hulls from hinging outward during sailing. Note there is a transport beam and a support beam. Since neither needs to work very hard if the deck support most of the structure the beams could be lighter alu pipes, 80mm dia or there abouts. You figure the thing out. The hinges are large and made from glass and SS pipe, they should be the length of the deck.

Some advantages are you can make your cat as wide or narrow as you want. The deck can also be shallower as long as the deck support the hulls without strong enough beams, but you can of course use heavier beams if you want to. Keep in mind the cat as drawed use the deck to support and stiffen the hulls and the lighter beams support the hulls and the deck.

The removable gin pole and removable winch hinges the cat close or open.

That's more or less it. I'm going to attempt the first one in the near future, got to sort some other crap out before I can begin.

[rayaldridge]

Fanie, that's a very clever idea. Looks as if it would work well for a big daysailing cat.

I'd steal the idea, but it wouldn't work for me, because the depth of the decks would take too much beam from the individual cabins. Edit: Although, thinking about it, maybe if the decks were open box structures, the cabins could extend into them. This is why I love this group-- makes me think.

You might not need the gin pole. Unless the boat is very large and heavy, you could start the fold by lifting up slightly on the deck seam, and then a tackle could pull the hulls together. The decks would rise up automatically.

[Fanie]

Hi Ray,

Doesn't have to be a large daysailer. If you go any smaller than that and with a thin decks just use alu beams. The decks can simply sit on the beams.

[Alex.A]

How about a scissor type that folds up along the central spine - but uses normal beams when flat? Slide in/out through tubes. The central spine could also be a tube/beam which could also be removeable - would mean that the hulls would need to be built with half of the bridgedeck attached.......

[elliott]

Many many people have spent many many hours trying to work out the best solution to the problem of a quick-folding cat with decent accommodation.

In the 1970's I built a 7.5metre flat flush-decked cat with a folding system as shown at top of sketch attached. The beams are each in three parts. To fold: you take bolts B and D out and one hull can then be pushed forward and round so that it ends up side by side with the other.

There wasn't much headroom so next year I took the deck off and built cabin tops with three removable beams and prior to launching fixed the beams in as the lower sketch. After launching you get some mug to hold the end of beam (E) up slightly; the end of beam at (G) lifts in sympathy then you hold the end of beam at (F) and push. The hulls float apart effortlessly and in complete control. When they are apart drop the ends and bolt up. What takes the time is the trampoline lacing. I use the boom as a fulchrum to raise the mast which works very well. I have launched it on my own several times.

Three photos attached 1) me having breakfast to show that it is possible in a folding cat with 1 metre wide hulls 2) another of the boat on trailer 3) another of boat on mooring. Twin hull accommodation is wonderful for those who want a peaceful nights sleep and privacy. Bridgedeck accommodation is wonderful for those who are not worried about those things.


That playpen type folding design - was it not produced a long time ago by PDQ in Canada? Anyway not important.

[Steve W]

Elliot, thats a nice looking cat,the expanding method you settled on is the same as the Macgregor 36 i used to own except that all 3 beams were fixed on the same side,the fwd and aft beams were in troughs held down by ss straps much like many beach cats.the mid beam was slid in to closed troughs(not tubes) with2 horizontal 3/4" bolts each side through the trough and beam. While the system worked well it took a lot of time to set up. The time consuming parts were, as you say, installing the tramp and nets but also assembling the chainplates,mast base and dolphin striker on to the mid beam as you were opening it up. I made a big change in this area by accepting that,as the beam weighed 105lbs bare, it was a two person job to instal it through the cabinside without causing damage to either the boat or myself anyway,i might as well keep it fully assembled at about 140lbs so i cut away the cabintop above the mid beam trough to allow the beam to drop in from the top, this was a huge time saver, the cuttout sections of cabintop were turned into lids which were installed over the beam. Another big timesaver which i did not do would be to raise the mid beam up to the top of the cabin and make the tramp in one piece all the way from the forebeam to the aft beam passing under the dolphin striker, it could then remain fully attatched and just hang down between the hulls when on the trailer, this is the way they do it on the Reynolds 33.The tramp is made of the polypropylene shade cloth and is not attatched to the mid beam at all as it is feet below it. The only problem i see with this is that forcing the hulls apart enough to get the last bolts in against the tension of the tramp may be problematic. Oh,the other big timesaver for assembly of my Mac 36 was the telescoping trailer i built (just like the smaller cat shown early in this thread) which allowed the boat to be fully assembled ready to sail while on dry land, the Macs mast which has a fairly large mast at 44ft was fairly easy to raise using the boom as a fulcrum and the mainsheet tackle with the mainsheet removed and replaced with the anchor rode,(you need 150ft) Because it was masthead rigged with inline shrouds and the chainplates and mastbase revolving around a round beam the mast was perfectly controlled athwartships by the cap shrouds, the best settup i have ever experienced on any boat.
So,to lower the mast the sequence was,
1/ Replace the mainsheet with the anchor line.
2/disconect the aft lower shrouds, swing them back and connect them to fittings near the aft end of the boom.
3/ Connect the main halyard to the end of the boom,the mast is now well supported at the top and middle.
4/ Connect the two fixed length cables which i made up,from the end of the boom to the cap shroud chainplate to prevent the boom centered when it is in the air.
5/ loosen the cap shroud turnbuckles to reduce friction. The chainplates are a simple 1 1/2"x 3/16" ss strap formed to wrap around the beam,(which is a 6 5/8" round tube)
6/ Run the spinnaker halyard fwd.
7/ Loosen the two clamp bolts on the mast base to reduce friction as it also rotates around the beam(also based on two straps same as the chainplates)
8/ Create some slack in the mainsheet and cleat it off.
9/ pull on the Spinnaker halyard to start the mast going fwd.
!0/ Put a couple of wraps around a winch drum and lower away under perfect control.
It is very rare where you can get the cap shroud and mast base pivot points in perfect alignment resulting in the mast being perfectly supported athwartships through the whole opperation.
You are right, PDQ did use a ladder beam folding system on a 27ft cat that they owned themselves,not a production boat though.
Steve.

[rayaldridge]

Elliot, that's a nice-looking boat. Makes me think I should try to work a knuckle into my design, but I'm going for simple, so maybe not.

Alex, my idea is sort of like what you suggest, except that the folding beams are load-carrying. I just have to make sure the locking mechanisms are strong enough. One thing I'm trying to avoid is having components of the system which are not attached to the boat at all times. I still remember the struggle I had when launching my old Tane. But your idea has a lot of merit, I think -- simplicity and strength and less weight.. Might be better than the idea I was going to use, or maybe better in combination.. I'll have to cogitate.

[ThomD]

"I'm wounded! Why do you think my new boat won't have a high performance potential? It will weigh only a little more than Slider, and have 220 sq. ft. of sail, compared to Slider's 140. It will have a longer waterline, and be able to carry its canvas in heavy air. It may not be a barn-burner"

That's my point. You can't seriously pretend it is all about the speed? The G32 won so many races in the great lakes, that they changed the rules, so they had to return to beating million dollar yachts with plywood 35 footers from the 70s.


", or as fast as the beach cat the rig came from (except in heavy air, where it should be pretty fast) but it was designed in part as an answer to those little tris that are being built to use donor rigs from beach cats. I'll be disappointed if it isn't fairly fast. (Imagine me sitting here with a sad face.)"

Of course it will be fairly fast, on some point of sail, in some set of conditions, with some set of expectations. I didn't much consider my remark since I am not all about the speed...

"Re the G32, with the best will in the world, I can't believe a boat with less of a righting lever than a Hobie cat and such a massive rig is really suitable as a cruiser. It may be possible to sail the boat safely, if one is hyper-alert, and reefs very conservatively, but the nature of cruising is that unexpected things happen. What may be safe on Long Island Sound will probably be a bit anxiety-arousing in a blow out on the ocean. The fact that the boat can be righted does not reassure me. The rig is fragile, and would probably not survive a capsize in a seaway-- in fact, there's a famous story about the boat being taken out for a test sail with a writer from Sail aboard, and losing its rig. Maybe I'm just a Chicken of the Sea, but I wouldn't get out of sight of land in a Gougeon 32. To me, if cruising is not relaxing, it's not really cruising."

Whoa, that is so off the mark. First I never suggested you build a G32, I suggested you consider it's moving bits as an alternative to making a cat that is beam adjustable. A 20ish foot boat with 8 foot beam is within the range of normal catamaran beam without any adjustment. Adding a water ballast and self-righting capability to that boat could be criticized in a number ways, but as underly conservative, I have a hard time seeing it. The reality is that with a standard rig, the G32 in half the required beam. A 20 footer, is 80% the current conventional beam.

Multihullers tend to be too beam fixated. Beam without weight = zero righting moment. It is a whole lot easier, up to a point to adjust weight than beam. In all likelihood the self righting capability on an 80% beam boat would never get used, so far from being a fragile string, it's overkill. The G32 can take on 1200 pounds of water ballast.

Where the Gougeons raced the G32, you easily loose sight of the shore, and it's cold, capsized conventional multis have had hypothermia problems. Jan has raced the G32 in the ocean, and capsized it 4 times and recovered it. But that just isn't what most people seem up for, and I can't blame them, but as I say, a G21 and a G32 would be very different animals.

I would point out that the Jarcat uses a 26 (24) foot spar on a 16 footer, with 8 foot beam. So putting a Hobie on a 21 footer, is hardly suicide. Ron Given designed a jarcat sized small cruiser that was self righting with body weight recovery.

Another part of the G32 system is the roller reefing main. Just a part of the safety puzzle. That alone with the greater weight of a 21 would keep it fairly conservative, in Jarcat territory, without the ballast or self-righting.

"The thing about Slider was that she was about the longest boat I thought suitable for fixed trailerable beam, and then only with her very modest rig. Looking at other cats, like the Jarcat, with similar beam but bigger rigs-- you start to see a lot of capsizes. I'm sure a good alert seaman can keep a Jarcat on its feet, but the Gougeon 32 is a whole other order of boat, and is that really what cruisers want?"

People want what they have seen in their neighbour's driveway. No basis upon which to design a boat. Again, we are talking about the gadgets on a 32 applied to a boat that has historically reasonable beam at trailerable to start with. Where some of those doo dahs are actually useful for stuff like raising the spar.

"I hate to be relying on this logical chestnut, but a number of the boats were built, at least 14. That strikes me as a fair trial. If the boat were a really good one, that should have been a big enough sample to propel the boat into general acceptance. But they were not very popular and they have a fairly low resale value."

I haven't noticed that. the boat went out of production because the Gs decided they couldn't hit a price they were comfortable with. They also seem to prefer not to compete with their clients. I have yet to see a resale ask price at less than what they cost when they were first sold. Often a lot more. They brought the boat to market just prior to a recession.

" There was probably a reason why the owners did not like their boats enough to keep them and use them."

I haven't seen that either. We have a local one. What is it they say? The average boat gets used like 10 hours a year. No boats are getting that much use. In this area it is all about the class racing for which it is ill suited. You would basically be racing yourself, where there are similar small boat classes with a lot of boats.

"For almost any other sort of boat meant for cruising, there are logs of cruises accomplished. Do any such logs exist for a G32? They've been around for a long time."

Numbers have to be larger for that. There are all kinds of boats out there you cant find anything about. The Gougeons have been cruising the C out of theirs, and yet all we hear is the sailing canoe stuff. Jan wants to build a smaller one that is even handier. I wanted to do that for about 10 years, but it is a complicated boat to build solo, and at the time pre-internet. Oram built a smaller G32, and calls it the most fun boat he ever owned. No pictures of that one, so I guess it didn't even exist.

"To be clear, I'm not saying it's a bad boat, I'll bet it would be a lot of fun to sail. I'm just saying it's not really suitable for cruising."

I depends what part of cruising you are after. I think it would be pretty great, where a high premium is placed on mobility, exploration. But no, not for the trailer trash set who are after cheap rum etc...

"In the choice between beam and water ballast, I would go for beam every time. I think it's safer and faster and gives more usable deck."

Well evidently not, since you aren't building a trimaran. That is why I think it is all just conventional thinking you've given up the first 33% of beam for ballast already, but that last little bit is a big problem. As far as the deck is concerned, I am not convinced. I would trade solid deck for netty deck, everything equal, at a fairly steep ratio.


"The trouble with shifting water ballast from one side to the other is that the process takes some measurable amount of time, and things happen awfully fast sometimes out on the water. Beam is always there, for good or ill. If I remember correctly, the water is removed from the G32 by bailers that depend on speed to function. What happens when the boat is taken aback suddenly-- all that weight will be on the lee side and no way to quickly get rid of it. I'm wondering how they handled tacking in heavy air, with that setup."

Right, but at 24 feet with 8 foot beam, you would be at open ocean beams without anything. Sure these days we prefer 12 feet on that dimension. While you can race the boat with ballast on one side only, or even no ballast, you can take ballast on both sides if you feel more comfortable doing it. The way they kept the performance equation in there was by careful hull design, and the boat will be heavier than some other options, but you are either scared or not. What is less apparent is why people are scared of the thing they wouldn't do. It seems to be like looking over Niagara falls and being scared as some people are just at the thought of it...

In my mind if you an come up with a revolutionary beam adjustment system, without all the usual nightmares, that would me major, and far more salable. If it really rocked, and was scalable, you will be rich. But it has been tried so many times. Failure, and I think the G style boat is a better direction,

[rberrey]

why not use alum tubeing with ears one top one bottem, 4pcs, join in the middle, three holes one for a pivit point, two to lock the beams in . 6 bolts with wing nuts sizzor open like a folding chair. rick

[rayaldridge]

"In the choice between beam and water ballast, I would go for beam every time. I think it's safer and faster and gives more usable deck."

Well evidently not, since you aren't building a trimaran. That is why I think it is all just conventional thinking you've given up the first 33% of beam for ballast already, but that last little bit is a big problem. As far as the deck is concerned, I am not convinced. I would trade solid deck for netty deck, everything equal, at a fairly steep ratio.,

Well, I did say "usable" deck, and the side decks of tris are not as usable as the center deck of a cat. And after all, we are talking about cats, not tris. Cats, in my opinion, are much better cruising boats than tris. Folding solutions for tris are well-developed-- thus my interest in doing the same for cats.

I've owned two cats with hard decks, and they really are a lot more comfortable, and I think safer than net. They are heavier, but the better footing makes for a safer boat to move around on.

Thom, you make a number of interesting points, though I remain unconvinced of the value of ballast for multihulls. Most of what makes a multihull good comes from its lightness. An overloaded multi is a slow multi, and an unsafe multi, or at least that's the gospel according to most multihull designers. In the small sizes we are speaking about, there isn't as much payload available as you'd hope. For example, the Simpson cat with the folding aluminum beams had only three or four hundred kilos of payload., and it was a fair amount larger than what we're talking about.

But I agree that there is a certain logic in the idea of compensating for narrow beam by using movable ballast, since that's how people sail beach cats without capsizing. But the displacement has to come from somewhere, and the added displacement needed to use water ballast is a design problem without an obvious answer that doesn't adversely affect speed, especially for a cruising boat.

I'd love to see you (or someone) build a 20 foot cat with trailerable beam and water ballast, and use a good beach cat rig. It would be very interesting to compare the solutions, and see which one had the higher performance potential. My opinion is that the light boat with the greater beam would be faster, but it's only my opinion. It would certainly be more comfortable, simpler to sail, less fussing with pumping ballast, and less anxiety arousing.

[dstgean]

No Dan, mine is blue hulls and decks,not in bad shape though.
Steve.

Could you comment on details of the boat? How would it be for coastal cruising? Is it rightable from capsize? What is the loading capacity before having draggy transoms or slapping the bridgedeck? Is the main set up to be reefable? How heavy is it?

Dan

[dstgean]

I'd love to see you (or someone) build a 20 foot cat with trailerable beam and water ballast, and use a good beach cat rig. It would be very interesting to compare the solutions, and see which one had the higher performance potential. My opinion is that the light boat with the greater beam would be faster, but it's only my opinion. It would certainly be more comfortable, simpler to sail, less fussing with pumping ballast, and less anxiety arousing.


Lighter is nearly always faster. However, it would be interesting to see a boat that's 20'x8'6" with a bit of water ballast. I'm doing most of that with my double Tamanu build. However, it won't have water ballast. I think it would be interesting to have the footwells filled with water ballast below, have a flapper valve or something that would allow the water to dump out of it's own accord when flipped 90 degrees, and allow easier righting by not having to pull that excess weight back over center. A 20' boat is pretty small and could be designed to accomodate the weight. But it won't be faster unless the lighter boat capsizes more often.

Dan

[rayaldridge]

Dan, what do you think your double Tamanu will weigh?

[Steve W]

Dan, thanks for the interest in the P cat, keep i mind that i have no actual experience with this boat as i just bought it 2 months ago and right now its under a foot of snow.
Ok,heres what i know, its 19ft x 8ft x 540lbs published DISP so i would guess you would subtract 300lbs (2x 1960s crew) to get weight ? The aft crossbeam is 4ft fwd of the transoms so that forces the crew to the mid part of the boat, i like that as it should help keep the weight centered. I read somewhere online that it will handle 4 people and still get up and go so i think a couple of people and gear for a week may work.I relly like the cockpit wells as even on my Macgregor 36 it was tiring on the legs to have them out straight too long.The wells drain through the daggerboard trunks but there is also a huge 3" drain tube running back thru the aft storage lockers to the transom.Is it rightable from a capsize? i would expect it to be as rightable as any other 19ft beachcat, so not so easy im guessing,maybe fill the mast with foam or a masthead float,maybe adopt some of the systems used on the G32. It would be easy to instal a fwd net a la the G cats which i have sailed extensivly and loved that feature(it has a full crossbeam at the bow) one could sleep there i think.The bridgedeck is pretty camberd so i may have to add some wedges to level it out to sleep on it otherwise i can see myself rolling off into the footwells. The rig is huge, 270 sq ft i think so it will definatly need serious reefing,maybe i can get a smaller main for cruising and put reef points in that or build a roller reefing/furling boom like the f boats and the G32 use,we will see.
I have a 1.2hp sears gamefisher for it,just 14lbs and stows easily in the aft locker. I will need a boom tent and perhaps a dome tent for the fwd net. In a couple of months my son and i will pull it inside and repair a hole in one hull,fill all the fastener holes in the decks and then paint it and then figure what to do with it,im excited about this cat.
Steve.

[dstgean]

Dan, what do you think your double Tamanu will weigh?


That's the big question. My beams have to be beefier than the stock hobie beams as I broke one during an upwind bash in 20+ knots--even in the lee of an island. My hulls are lighter than the H18 hulls, so it might be a close thing. I'm secretly hoping 400# is possible even with a hard deck.

Even as I do this boat, I'm kinda planning a version of Michael Schacht's Beach Cruiser with dory hulls and a hard deck. Shallow Water capable, rightable even solo, big enough for a cruise with 2 + gear or a big daysailing posse, looks like my vision of a "polynesian" boat without going all Wharram, etc. Not going to happen right away as I've got too many outriggers to even broach the topic with my wife.

http://proafile.com/images/design/beachcruiser_profile.jpg
http://proafile.com/images/design/beachcruiser_1.jpg
http://proafile.com/images/design/beachcruiser_2.jpg

I'd build something like that in a heartbeat--even with the v hulls which aren't so S. Florida flats friendly. Not having to mess with boards is nice even without the better pointing ability they offer. I'd also go with some footwells like Gary Dierking's Tamanu as I love the seating comfort and the self bailing aspect. Additionally, the H21SC wings might be a nice touch even though they don't quite go with the 60's CSK look.

Dan

[dstgean]

Dan, thanks for the interest in the P cat, keep i mind that i have no actual experience with this boat as i just bought it 2 months ago and right now its under a foot of snow.
snip
im excited about this cat.
Steve.

Looks cool! The one I saw had a great look as well. The crown of the deck is a bit disappointing though. Should be a solvable problem though. I was thinking it might be interesting to have two panels fold out to cover the footwells and have an 8x whatever length the cockpit is area to camp on. Additionally, I thought a couple watertight bulkheads fore and aft and a big hatch like I have on my Tamanu coupled with the front tramp would make this stock design into my own custom cruiser.

Dan

[Steve W]

Dan, the p cat has watertight bulkheads aft but the hatches in the aft deck are just shoebox style held down with a bungee inside so i need to make them watertight. I could put hatches fwd for storage. I like your idea of panels over the footwells.I think the bridgedeck is about 6ft fore and aft. I really like the Beach cruiser with the CSK look especially the sliding gunter rig,it would go under a lot of the bridges on the ICW just dropping the peak.I spent 3 weeks last spring camp cruising the west coast of Florida on a Egret sharpie with a gaff rig and we were just a foot to much air draft for most of the bridges and the p cat is taller still.
Steve.

[dstgean]

Dan, the p cat has watertight bulkheads aft but the hatches in the aft deck are just shoebox style held down with a bungee inside so i need to make them watertight. I could put hatches fwd for storage. I like your idea of panels over the footwells.I think the bridgedeck is about 6ft fore and aft. I really like the Beach cruiser with the CSK look especially the sliding gunter rig,it would go under a lot of the bridges on the ICW just dropping the peak.I spent 3 weeks last spring camp cruising the west coast of Florida on a Egret sharpie with a gaff rig and we were just a foot to much air draft for most of the bridges and the p cat is taller still.
Steve.

Alternately, you could go with a synthetic forestay attachment like Slider has and just tilt the rig back a bit, motor under, & tilt it back up. You'd need some sidestays @ 90 degrees like Mike Lenemann's Beach Cruiser 22 concept to keep the rig centered though.

That trip sounds fun! How often would the reduced draft of the dory hull come in handy vs. the boardless shape of the Beachcruiser shown above?

Dan

[Steve W]

I think the sharpie draws about 2ft and has a centerboard which gives a bit of advanced warning before running aground which we did often but could get out and push if needed, the Egret is about 28ft so it draws more than the beachcruiser. Years ago i had the use of a G cat 5m for a summer which had symetrical deep vee hulls with no boards and was a pretty good compromise, it also had the bow tramp which i really liked.
I will definatly looking at all the options to reduce air draft and tilting it back will probably be the go, im not going to change the mast. This boat is missing only one thing and that is the mast base so i have the opportunity to design and fab a new one to facilitate easy raising and lowering. One idea i have had is to look for a dome tent of a dimension of about 8' x 6' with doors in both long walls and make some fittings for the 4 poles to sit in on the gunwales and cut out the floor,this way i can sleep on the bridge deck or sit on the edge of my bed with feet in the footwell,and have a door to the tramp and be able to access the aft hatches. I wont really start to develop until i get it inside in febuary.
Steve.

[dstgean]

Lost a reply, let's try again...

Steve, I think it's ironic that what I'm coming to view as the perfect beachcruising cat was designed in 1958 and in production by 1960! I like your thinking about what would make the PC19 a good cruiser. I wonder how a boat designed to this general idea would sell on either the homebuilding or even the production market. The PC 19 is dangerously close to what I'm looking to achieve.

it's close to the right length
it has a flat(ish) hard deck
it has footwells
the weight is concentrated amidships
it could be used with a fairing for outboard power like the gougemaran
with floorboards or filler panels the central section could be a big sleeping platform
it could sport a front tramp pretty easily
it could be rigged to reef pretty easily


If I were designing a boat like this to build myself, I'd be looking hard at Michael Schacht's Beach Cruiser CSK look and Mike Leneman's BeachCruiser22. I think I'd prefer a boat about 20-21'x8'6" with footwells and possibly hiking seats like the H21sc.

Are you thinking of modifying yours once you can get it inside?

Dan

[Steve W]

Hi Dan, it remains to be seen how the boat will handle a load of 2 - 3 people and some lightweight camping gear and supplies for a week or two of gunkholing.The boat passed its initial test which was trailability behind a modest vehicle as we towed it 1400 miles including through the mountains of west virginia behind a 1996 VW Passat TDI with a quarter million miles on it and we achieved 30mpg through said mountains, down from 52mpg on the way out but none to shabby notwithstanding. Much to my surprise the proper factory made galvernized trailer was purchased new in 1996 and it shows no sign of having seen salt water so appart from rotted tires from sitting for 12yrs its perfect,i upsized from 8" to 12" galv rims and tires when i got it home.
I agree a little longer and full legal width would be great as would a little more freeboard and displacement but hey,it is what it is,now i need to optimise. I dont think we will go with the hiking seats yet,hobies are a 40lb add on on the 18. Mainly we will be doing some minor repairs,a full awlgrip job,replace all the old hardware with modern stuff,probably at least install the bolt rope track on the hulls for the fwd tramp,fab a motor mount and come up with a reefing system and in general get all the sailing systems working efficiently including righting systems so we can use it and then pick away at it over the summer.A lot of mods wont become apparent until we put some miles on it.
Steve.

[dstgean]

I agree a little longer and full legal width would be great as would a little more freeboard and displacement but hey,it is what it is,now i need to optimise. I dont think we will go with the hiking seats yet,hobies are a 40lb add on on the 18. Mainly we will be doing some minor repairs,a full awlgrip job,replace all the old hardware with modern stuff,probably at least install the bolt rope track on the hulls for the fwd tramp,fab a motor mount and come up with a reefing system and in general get all the sailing systems working efficiently including righting systems so we can use it and then pick away at it over the summer.A lot of mods wont become apparent until we put some miles on it.
Steve.

I'm loving it. It seems like a pretty good boat for what I'm looking to do without having to start from scratch. All the stuff I listed is simply how I would like to kit out a boat like the PC 19.

Dan

[Steve W]

Dan, buy that one on catsailor,its cheap and looks nice, course it adds up, i paid $305 for mine on ebay,it was sold by boatangel and they add $180 and then i drove 2700miles round trip to get it so by the time i paid for fuel and a couple of nights in a motel along the way and put new rims tires and a tongue jack on the trailer and bought a motor im into it for nearly $900 already and ive just started. There are no cheap boats i guess. When i get it inside and dried out i will weigh it and find out for sure if its heavy.
Steve.

[dstgean]

Dan, buy that one on catsailor,its cheap and looks nice, course it adds up, i paid $305 for mine on ebay,it was sold by boatangel and they add $180 and then i drove 2700miles round trip to get it so by the time i paid for fuel and a couple of nights in a motel along the way and put new rims tires and a tongue jack on the trailer and bought a motor im into it for nearly $900 already and ive just started. There are no cheap boats i guess. When i get it inside and dried out i will weigh it and find out for sure if its heavy.
Steve.

I've thought about it a bit, but the 16 hour one way puts a damper on it. Less fun is telling my wife I buoght another cat. I should thin the fleet a bit first as I currently have a H18, a Ulua, a Tamanu, and adding a PC 19 would put me squarely in the doghouse. Now if I sold the H18 or the Ulua...maybe then. It does seem like it is mighty close to what I'd be looking to build, so the hours and cost of driving are paltry if I had the go ahead. My wife is wanting SUP's though at present.

Dan

[Steve W]

The problem is i had actually been looking for years for one but most are on the west coast,this one,even though a long trip to get it was the closest id seen so i had to act.I was thrilled to get it. I have too many boats also but no wife to answer to.
Steve.

[Skint For Life]

This is not far from where I live, I thought it may interest you guys.

pacific cat:

http://www.trademe.co.nz/Trade-Me-Motors/Boats-marine/Yachts-sail-boats/Small-sailboats/auction-337773884.htm

[Steve W]

Hey,thanks for the trade me link Skint, i wonder if they were imported there or if that one was brought in by an individual. Really great set of photos, i see it has all the same old crappy hardware as mine and all the old fastener holes from where stuff has been moved. Im going to remove everything and fill the holes, paint it and layout all the new gear to suit me. You can see those huge 3" cockpit drains through the transoms. That spinnaker is the same color as mine i think, my whole boat is the color of the deck on that one.
Steve.

[dstgean]

This is not far from where I live, I thought it may interest you guys.

pacific cat:

http://www.trademe.co.nz/Trade-Me-Motors/Boats-marine/Yachts-sail-boats/Small-sailboats/auction-337773884.htm

Skint,

Thanks for the photos. Lots of details and the original info on the boat as well! I wish there were some dimensions of the hulls though.

Dan

[dstgean]

Hey,thanks for the trade me link Skint, i wonder if they were imported there or if that one was brought in by an individual. Really great set of photos, i see it has all the same old crappy hardware as mine and all the old fastener holes from where stuff has been moved. Im going to remove everything and fill the holes, paint it and layout all the new gear to suit me. You can see those huge 3" cockpit drains through the transoms. That spinnaker is the same color as mine i think, my whole boat is the color of the deck on that one.
Steve.


Good plan. The hardwary has improved so much it's hardly comparable. Make sure to keep us updated on your boat.

Any idea why the hulls have such a long slot for a daggerboard? It seems more like a centerboard slot at that length.

Dan

[Steve W]

Dan, your right about the daggerboard slot,i have no idea why it is so long,the daggerboards are very typical eliptical shaped fiberglass molded ones with a chord of 11 1/2" x 42" overall length, it sure gives a lot of ability to adjust balance, orrrr,i could use a pivoting centerboard like a Hobie 18 or Tornado. Might be better for a cruiser. Oh,my boat came with 2 nice glass boards and 1 black anodised cast aluminum board that weighs a ton and 2 decent but missmatched glass rudder blades and 2 decent wood ones.
Steve.

[ThomD]

"Well, I did say "usable" deck, and the side decks of tris are not as usable as the center deck of a cat. And after all, we are talking about cats, not tris. Cats, in my opinion, are much better cruising boats than tris. Folding solutions for tris are well-developed-- thus my interest in doing the same for cats."

By all means solve the folding cat problem, I can't wait. My point about tris wasn't their deck space but their righting moment. To the extent that one says on wants to rely on beam not bulk, the tri is your friend, You can go square with a tri's 100% beam. and 75-80% is nothing these days. So to the extent that you are happy with 50% beam in a cat, you are already out on a limb so to speak, as relates to accepting bulk over beam.

"I've owned two cats with hard decks, and they really are a lot more comfortable, and I think safer than net. They are heavier, but the better footing makes for a safer boat to move around on."

Which is why you don't really want a folding one. The Gxx will be very solid.

"Thom, you make a number of interesting points, though I remain unconvinced of the value of ballast for multihulls. Most of what makes a multihull good comes from its lightness. An overloaded multi is a slow multi, and an unsafe multi, or at least that's the gospel according to most multihull designers."

This is the nitty gritty of the problem, and what one has to understand. Two big points (as I am sure you know) are one: No weight, no righting moment, so weight is not your enemy but bad design or overloading are. Two, the way the ballasted multi works is to start out of the box on weight. The G32 has to beat conventional ratios, so that ballast can be added partly within, and partly above conventional weight ranges. It also has to be very easy to push so that it isn't standing up under too much sail, but keeps sliding out from under the gusts.

The problem I see is how to do this on smaller sizes where the boat isn't as slippery, and where the displacement isn't as large. Ultimately you can't do it. But that is because small multis don't work, you do have to give up something to put 5 berths on an 18 foot trimaran, as some have done with highly popular designs.

"In the small sizes we are speaking about, there isn't as much payload available as you'd hope. For example, the Simpson cat with the folding aluminum beams had only three or four hundred kilos of payload., and it was a fair amount larger than what we're talking about."

Same thing with my tri, on paper it is a disaster, there is really about 200 pounds, but it sails nicely, and we have fun. At the end of the day displacement goes up to the cube of length, and small boats are always a compromise.

"But I agree that there is a certain logic in the idea of compensating for narrow beam by using movable ballast, since that's how people sail beach cats without capsizing. But the displacement has to come from somewhere, and the added displacement needed to use water ballast is a design problem without an obvious answer that doesn't adversely affect speed, especially for a cruising boat."

I agree with that. So trick one is you have to build a boat that is 66% the weight you would expect. That isn't as hard as it sounds since the hulls you build are not efficient, and you can save money and time doing it, but you will scare the last possible customer away, because they will not want to do tortured hulls... Which I don't understand, it's as if a boatbuilding saviour sent multihull builder's his best idea to rescue them from the drudgery of building slow to build, expensive, and slow to sail boats, but they just rejected it.


"I'd love to see you (or someone) build a 20 foot cat with trailerable beam and water ballast, and use a good beach cat rig. It would be very interesting to compare the solutions, and see which one had the higher performance potential. My opinion is that the light boat with the greater beam would be faster, but it's only my opinion."

And you would be right. If the idea was to make a boat that sailed off a mooring, the wider boat, at these beams is going to be the one I want. I should point out that in light air the Gxx boat will be the lighter and have lower drag, which is why they beat all those million dollar multis with the 30K production boat. But none of those races started from the driveway. What I am after is a boat that is fun to sail starting from the driveway. Really, it is too much trouble to create a narrow beam, trailerable boat unless it does a lot for you. I already have a demountable tri, that I am stuck to a mooring with. To do another build for a boat that folds (twice the building time generally), it needs to have a boat that launches like a bassboat, If I won't use it I don't need it. I think the Gxx will beat you on the water some days, from the driveway everyday, and from the workshop by a significant factor, or maybe not (depends on your solution).

" It would certainly be more comfortable, simpler to sail, less fussing with pumping ballast, and less anxiety arousing."

- Comfort i don't see...

- Simpler to sail I think depends too much on specifics, unless we are double counting the ballast issue.

- One does have to handle the ballast at some level. I have decided on going no motor for a while, and without a motor, I don't know how one gets the ballast on in heavy weather, but with a motor I don't think the ballast is a problem.

- Anxiety I don't know about. It is rightable, and only slightly less beamy. It also has the capacity to be nailed to the water with a lot of ballast. It is an integrated solid structure, with lower loading, a lot of folding designs are pretty hardware dependent. I think it is the difference between worry and risk. We don't worry about the things we are already accustomed to pushing to the back of our minds. This design comes with new worries, but is the risk lessor or greater?

[outside the box]

Hi There
We looked at the P/Cat from Trade Me add Skint posted.
It has cast Bronze daggerboards, after market the owner thought in an attempt to add ballast. The prior owner had brought it in from The USA with him when he moved to New Zealand.
The Boat in general was in poor condition with the owner doing some home handy man work on relocating loose fittings with no backing blocks so fittings into raw chop strand. He had also tipped it over racing off Oamaru, in the South Island so think open Coastal Ocean, he brought it back to the trailer loaded it with water still in hulls then upon pulling trailer out of the water the hulls crushed damaging them badly. The resultant repairs were home handy man at best, executed by riveting aluminium to the inner hull then bogging over alloy plate with a fairly rough paint job over it. quite fair but marginal as a repair of substance. He also sealed the rear hatch's down and put new drain pipe through the rear of hulls that drain the foot wells as they take water in as she is sailed through the dagger board slots, again the replacement of the drains was home handy man at best.
The mast had two repairs to it one externally sleeved and one welded, the mast also had a slight bend in it. He raced it against Paper Tiger and Hobie 16 and said in light airs Hobie 16 would sail away from him but in a good blow he could sail rings around the Hobie. The chap selling it was a nice genuine guy who disclosed every thing about the boat.
A few photo's attached from when we viewed it and the rest of the promo doc he had for it. The repairs to mast and hulls are visible in photo's when enlarged. Also the Hobie 16 and Paper Tiger are visible in back ground of photo's.

[dstgean]

Too bad it was in poor condition. Interesting cats though, and thanks for the additional photos.

Dan

[rayaldridge]

Thom, it is always a pleasure to read your carefully considered posts. You make me think. I'll just address one element of your post, though there's lots there.

"Well, I did say "usable" deck, and the side decks of tris are not as usable as the center deck of a cat. And after all, we are talking about cats, not tris. Cats, in my opinion, are much better cruising boats than tris. Folding solutions for tris are well-developed-- thus my interest in doing the same for cats."

By all means solve the folding cat problem, I can't wait. My point about tris wasn't their deck space but their righting moment. To the extent that one says on wants to rely on beam not bulk, the tri is your friend, You can go square with a tri's 100% beam. and 75-80% is nothing these days. So to the extent that you are happy with 50% beam in a cat, you are already out on a limb so to speak, as relates to accepting bulk over beam.


I think that tris are actually very different from cats when it comes to analyzing their response to rough conditions. I would say that despite their wider overall beam, tris are more vulnerable to wave-induced capsize than cats, due to the much higher roll moment of inertia possessed by cats.

I would not be happy with 50% beam, in a cat with a lot of sail area in proportion to its size. Slider, at just under 16 feet, has a BOA of 8.5 feet, and as you know, I put a very conservative rig on Slider. The new boat, at 19 feet 8 inches, will have a beam of at least 12 feet, perhaps more. (I'm currently playing with a model, attempting to work out a beam system that allows the rig to remain more or less taut when folded, Not easy!)

Let me add that I think beam does equal comfort. A narrow beam cat is less comfortable in a seaway than a wide beam cat-- I think this is easy to demonstrate by comparing the motion of a monohull to a cat-- and realizing that the narrower the beam, the more like a mono the cat will behave.

The goal with Slider was a cat as easy to launch as a johnboat. I think that she largely succeeds, though raising the mast may undermine that goal. But the mast on Slider is not tall, and is rigged in such a way that everything can remain attached when lowering it into its transport crotch-- boom, sail, sprit, etc. The forestay is tensioned via a Dyneema purchase, so securing the mast in an upright position is as easy as hauling on a line and cleating it off.

The new boat can't be that easy, since the rig is much larger, and the mast is much taller, and is a rotating mast. But the goal with the folding system is that it take a matter of minutes, rather than hours to expand into sailing beam, and that the rig remain in place when the boat is folded, so it can be dry-sailed with convenience similar to a dry-sailed mono.

Anyway, wonderful discussion!

[dstgean]

I did a quick look at Wood's offerings in the sub 25' range and his consistently come out at 58%-66% for his racier offerings.

Dan

[Steve W]

Ray,at 12ft beam on a 20ft cat you are at about 60%,my feeling is that the higher you go the more prone you are to diagonal tripping and also the jerkier the motion in a seaway.My old Macgregor 36 was 36x18 and had a very nice motion with none of that jerky motion ive experienced on bigger bridgedeck cats although it was probably more atributed to flexability. A lot of time can be saved at the ramp by streamlining the small things as much as the folding system itself. One place you may want to look for inspiration for a folding system might be the cross strut geometry on those cheap pressed steel sawhorses you can buy at the bug box lumberyards.
Steve.

[rayaldridge]

Beam is a very complicated subject, isn't it? I don't think 12 feet is too much on a 20 foot cat, since a number of designs I admire use a similar beam ratio, as Dan mentioned..

One aspect of it that I've wondered about a lot is the question of handiness. Slider is one of the handiest boats I've ever sailed, monohulls included. She never misses stays, and no particular technique is required to get her to tack. I've wondered how increasing the beam relative to LOA affects handiness. My suspicion is that the wider the beam, the less handy the boat. This issue is further confused by my intention to use a single central rudder on the new boat. I'm told that this does not negatively affect steering, and I hope that's correct. A single rudder (and board) on the centerline spine simplifies folding substantially, because there is no tiller bar to complicate matters. Also means the boat can be steered while folded.

Steve, in a sense I'm using a similar technique to stabilize the beams when unfolded. I like hard decks on cruising cats, even tiny ones. The plan is to hinge the decks along the centerline spine, so they can be folded up and bungied together before folding. When the boat is unfolded to sailing beam, the decks drop down and lock onto the hulls.

[Steve W]

I agree on the hard decks if you can make it work (which im sure you will) dont be afraid to use a single daggerboard in one hull if it makes more sense structurally,it really makes no difference sailingwise,i think having one in each hull is more about mans insistance on symmetry than anything else. I think on the handiness subject i suspect that the wider one goes the more important ackamman angle becomes which of course requires two rudders, however Kelsal uses a single rudder on some wider boats i think but no idea how it worked out.
Steve.

[catsketcher]

As to handiness Ray - if you go wider you increase the roll moment of inertia. That is why cats are better in beam seas than tris. The discussion earlier about tris and their higher beam is fine in a static sense but one very good reason that cats do not have to be as wide as tris is because they have significant masses at their maximum beam. Tris have most of their mass in the middle.

To understand roll moment of inertia think of a pole with two weights on it. If you get the two weights in the middle you can swing the pole easily. Now move the weights to the ends of the pole. The pole is now much harder to swing around.

This is one reason cats don't tack as well. You have to accelerate one (heavy) hull relative to the other and this takes energy and speed. Tris being more like the weight in the middle scenario are much quicker to tack. They also only have one hull in the water during a portion of the tack.

Roll moment is a bugger when tacking but great in dynamic situations like gusts and waves. Cats have more so can be narrower.

Diagonal stability is only a problem if you do the silly thing by saying - My cat/tri is beamier now I can put more sail on it. Well you can if you only go on a reach but a square run will find you with exactly the same fore and aft stability as before and then you are closer to capsize. Although going wider will mean that the boat gets a bit heavier.

cheers

Phil

[rayaldridge]

Steve, you're right about the single daggerboard. Slider has only one big daggerboard in the port hull, and it works wonderfully well. If I'm remembering correctly, the MacGregor 36 was originally produced with a single daggerboard, but the outcry for symmetry among potential customers was so loud that the design was altered. Despite the lessened efficiency of a non-end-stopped board on the central spine, I'm thinking of going that way, because the cabins are so small-- and for a couple of other reasons, including curiosity.

Phil, I agree completely. In fact, up in post #69, I said, "I would say that despite their wider overall beam, tris are more vulnerable to wave-induced capsize than cats, due to the much higher roll moment of inertia possessed by cats." This is a point I try to make whenever the safety of cats vs. monohulls comes up, as it still does, despite all. I remember long ago reading the report on the Fastnet disaster. When I got to the part about dismasted vessels being subject to repeated capsize, due to the missing inertia of the masts, I realized that had there been cats in the Fastnet race, it was much less likely that they'd have been capsized in the first place. I think you can look at other bad weather races with mixed entries-- the 1998 Sydney-to-Hobart Race is an example-- and see that the cats fared better, in terms of capsize, than the monohulls.

Slider tacks reliably in all conditions, with all sail combinations, although her beam to length ratio is slightly higher than 50%. I've always suspected that was because I gave her more rocker than is thought to be ideal, because it was the only way I could get enough displacement for two people and a camping outfit in 16 feet, and still keep the hull fineness to 10:1. I'm hoping that going to a 60% ratio will not make the boat difficult to tack.

[Steve W]

Ray,you are right about the Macgregor 36,mine was a 1979 with one board and it was not great at tacking but it had less rocker than most cats. I once talked to a guy who used to be a dealer back in the day and he was running a 1979 single board boat and a 1982 boat with two boards as cattlemarans on Galverston bay and licensed for 16 passengers,he swore that the single board boat tacked more reliably than the other. I only brought up putting a board in the hull because it may be difficult to adequate latteral support to a board in the center, i wouldnt worry about the lessened efficency of the board in the center,its just one of the many tradeoffs.
Steve.

[rayaldridge]

Steve, I plan to stabilize the central spine with water stays. This will be important for a couple of reasons. One big one is that the Nacra 5.2 rig I bought for this boat has the tack quite low on the mast. In order to clear the cabins and give the crew good visibility under the sails-- one of the nice things about Slider's setup-- I have to raise the step well above the center deck. The center spine is an I-beam with a ply web and timber caps. By stabilizing the bottom of the beam with water stays beneath the deck, I hope to stabilize the step, which will involve boxing the beam in way of the step. Because the Nacra rig has a rotating mast, that stability is really important.

Re single daggerboards-- I decided that the single board was the best solution partly as a result of the John Shuttleworth article that dealt with this issue.

http://www.john-shuttleworth.com/designs/S70design.html

I steal from the best!

[CT 249]

I realized that had there been cats in the Fastnet race, it was much less likely that they'd have been capsized in the first place. I think you can look at other bad weather races with mixed entries-- the 1998 Sydney-to-Hobart Race is an example-- and see that the cats fared better, in terms of capsize, than the monohulls.


Ray, the reason that no cats capsized in the 1998 Hobart is that there were no cats in the race! It's a rather extraordinary piece of evidence to use to show the supposed superiority of cats.

There were no cats in the Fastnet race but there was one tri in a parallel multihull race that was cancelled due to lack of entries. The tri capsized with the loss of four lives (i.e. a 100% death/competitors ratio, compared to the loss of 15 of the 2000+ monohull sailors and four of the small number of cruising yachties in the area).

While cats are, of course, different to tris it's hard to see the Fastnet experience as indicating that it was much less likely that a cat would have capsized.

The "mixed entry" or parallel races here have seen far more cat capsizes than mono capsizes. Here's one example -

http://forums.sailinganarchy.com/index.php?showtopic=24488&st=0

but the Brisbane-Gladstone has plenty of others.

I'm NOT saying that monos are better or safer than multis - I've encouraged most of the people closest to me to go sailing multis offshore - but it's hard to let a claim as false as one that there were cats in the 1998 Hobart go past without pointing out the truth.

There have been many false claims made about mono safety, such as the person here who claimed that lives had been lost on monos in the B-G (not true, but several lives were lost in the tri Australian Maid in 1972). Imagine how you'd feel if there were false claims being made about multi safety - There's no reason to make false claims about mono safety either. This sort of stuff just widens the mono/multi divide, like the repetitions of the (false) claim that the NYYC banned cats back in Herreshoff's day.

[rayaldridge]

I'm sorry-- I got it wrong, it wasn't even a race. It was the Queen's Birthday storm in 1994 (http://lists.samurai.com/pipermail/passagemaking-under-power/2005-April/001034.html). That's a pretty big mistake-- my brains must be running out of my ears. At least I was in the right hemisphere and the right decade!

Interesting pictures here (http://www.youtube.com/watch?v=FddHsVTLbqE).

I think maybe I didn't make my point very well, which is that a cat has vastly more roll moment of inertia than a monohull or a tri. This makes them less vulnerable to wave-induced capsize. I don't know if anyone disputes this, but physics is on the side of the cats.

[cavalier mk2]

The Newick tri Buck's Fizz that capsized during the Fastnet storm was found upside down with the daggerboard extended. It appeared they had been laying ahull but didn't raise the board for the necessary side slip. Some tri designers such as Bernard Rhodes and Ed Horstman advocated carrying weight in the amas to increase the roll moment of inertia while others suggest the buoyancy in the leeward ama will counteract the roll moment. Amas that are a bit immersed at rest would work more like a cat and less like a catapult than high dihedral versions. The old mono trick from the days of working sail of hauling a weight into the rigging to increase the roll moment is something to be considered for tender boats. With the variance in individual designs it is hard to generalize but monos that lose their masts would appear to be in worse shape than multihulls. It does seem that most of the recent cruising multihull capsizes of both trimarans and catamarans have been do to wind force.

[ThomD]

Did you find that Slider at 8.5 feet was uncomfortable? Why would slider at 21 feet and 8.5 feet be uncomfortable? Assuming she was upright? :) Monohull beam is a totally different thing, because the boats depend so highly on the external ballast with little immersion happening with roll. So they can get a nice pendulum underway.

Anyway, I don't mind what kind of cat you built. I will be excited to see anything you come up with. The Seaclipper folding design shows that not all the practical, cheap, effective, ideas have been tried.

I think there is a muscle car vs. GT kind of deal here. You already have a rig, and an OAL in mind, so you have to go with the beam that requires. My 24' x 18.5' trimaran moves along nicely under Hobie 18 and baggy sails, and sometimes gets pretty animated. So maybe you will need more beam. Whether one could configure a 21 foot boat with 8 foot beam that would have a lot of efficiencies is another mater.

[rayaldridge]

Just a slight update. I'm actually building the boat I was talking about now.

http://slidercat.com/blog/wordpress/wp-content/uploads/2011/07/tapedup.jpg

Of course, it's gone through dozens of changes. As I may have mentioned, my motto is to never make up my mind until I have no other choice.

I had something happen to me that in retrospect is pretty funny. I had the first hull wired up, and as is my habit, I tabbed between the wires with little epoxy fillets. I removed the wires, and was starting to fillet and tape the hull at the bow, when I noticed I'd missed a couple of wires. As I started back toward the open transom to pull them, I heard a terrible ripping sound and I dropped about a foot. The only way out was the transom, so as I galloped aft, the hull opened up most of the way.

More here:

http://slidercat.com/blog/wordpress/?p=559