Cheap Multis and Projects

[Redreuben]

Just curious, how much would a minimal desalination set up weigh with panels and all the bits to make it work ? 30kilos ? On a smaller boat that’s 30 litres of water storage you forego for complexity and maintenance cost.
Just thinking allowed [emoji2]

[Buzzman]

Bloody Sandgropers, weighing in on someone else's parade.....

[WINK]

It's OK, reuben, you are "allowed" to weigh in, whether quietly or 'aloud'....

But it's a good point!

Katadyn quotes their e40 as weighing around 35kg dry, so 1.5 jerries equivalent.

So on a smaller vessel, or one on short coastal journeys, 2 jerries is only 5kg more than the watermaker. And a heck of a lot cheaper!!!

BUT, even if operating on the meagre 'minimal water consumption' rate of 4-5L/person/day, those two jerries add up to only 8-10 days for a solo sailor, so "maybe" enough to get from Sydney to NZ on a fast multihull.....

BUT, if cost was an issue (which is often the case for those on smaller vessels), adding an extra jerry only adds 20Kg and would add the extra few days with margin to get safely to NZ....

And if it rained along the way (not impossible) and the sailor had a well-proven rain catchment methodology, even 1 jerry might be enough, supplemented and refilled by rainfall along the way.

This might work Sydney to NZ, but probably not a great plan for crossing the Atlantic in the doldrums or ITCZ where rainfall can be scarce.

Now, if that 'small vessel' had TWO people aboard, then doubling the qty of water doubles the weight/mass/load, in which case, the watermaker starts to look attractive again...

A 20-30 day passage across the Atlantic (about average) might require 100-150L of water minimum - no showering - for one person. Bear in mind most boats have at least one additional Mate/Crew, and that's 200-300L, or 300kg.

So at those sorts of passage distances, that 'complexity' looks mighty attractive on a super-lightweight multihull looking to save every ounce in weight. In which case a 35kg watermaker, and maybe 3 jerries weighing 60kg is less than the 100kg min for a solo sailor not bathing.

And with the watermaker you could technically bath daily and replenish.

If you want SWMBO to come along, I'd reckon that would be an imperative.

YMMV



It's got to be horses for courses, don't it..???

[owly]

20L....... absurd!! That's an ridiculous figure. If you need 20L a day, I suggest that you forget passage making and stick to short coastal hops...... I've never heard anybody else suggest anything even remotely approaching that figure. Watermakers are fairly new technology, but ocean crossing in small boats is not. A crew of 4 on a cat crossing the Pacific... say 3 weeks...... that's 1680 liters / kilos of water or close to 3700 lbs...Who has tankage or load capacity for that kind of water even on a monohull?



Normal practice is to do salt water bathing with a brief fresh rinse.......... someone needs to waste that much fresh water is no sailor. Many passage makers have budgeted for 1/10 that figure....... Water economy is not difficult. I suppose you are one of the "condo cat" crowd............ to each his own.



H.W.

Originally Posted by Buzzman

Just to be clear, I'm not stating you *can't* get by on less than 20L per day - including bathing - just that this is not easy without adopting serious water economies.

For example, as someone else suggested - just stop bathing for the week(s) of your ocean passage.

Not terribly practical, as salt would no doubt build up and cause chafing... but you see what I mean.

My comment was based on the obvious - that multihulls need to keep load weight to the minimum, or suffer a reduction in performance - so the recommendation of a couple of jerrys of 'emergency water' and a solar-PV-powered watermaker is the 'most appropriate' methodology for ocean-crossing multihulls. [IMHO]

But as the Rose Noelle crew proved, even an upturned hull can be used to capture enough rainwater to keep body and soul together, so 'capture methods' are also very well worth considering, especially given the acres of deck space on the average multihull that could be covered with a tarp to collect water.

As any hydrology student can tell you, increasing the area of the 'roof' dramatically increases the volume of rain 'captured' in any given 'rain event'.

I suspect (not having tried this myself) that a typical fore hatch fabric air scoop could be detached from the hatch and re-rigged as a rain-capture device, thereby killing two birds with one tarp, so to speak.

And we were talking about reducing weight....



YMMV

[Redreuben]

Buzz;
That’s 40kg/l deducted from your original tankage or payload and you haven’t calculated for solar or additional batteries and electronics.
So a Jerry is 8-10 days worth above what you already had. Plus rainwater.

[Buzzman]

reuben
True, but I'd assume solar and batteries were extant. Possibly need one panel to run watermaker, daylight hours blah blah.... Only a few kilos extra if any.

Like I said, the real issue is the longer passages where you'd have to carry 200-300L of plain water in tankage, OR just 20-40L of tankage plus the watermaker.

So 300kg vs 75kg.

The 225kg difference is another crew member and 120kg of food and/or other gear.

But I agree, for shorter passages it's not so mission critical and an extra jerry is way easier and cheaper.

[Buzzman]

Originally Posted by owly

20L....... absurd!! That's an ridiculous figure.
H.W.

owly
It wasn't me who argued for 20L per day! Quite the contrary!

But we were discussing (up-thread) the difference between needing / wanting fresh water for showering and how much that would use up.

In which case 20L per day might not be adequate, and therefore you would *need* a watermaker, even on relatively short passages.

The other major issue - strictly and specifically for multihulls - is that overloading them slows them down and essentially does away with their main advantage (being light and able to sail faster offering shorter passage times than most monos).

BUT, it's crucial not to overload a multi, and they generally only have fairly small 'live load' carrying capacity - hence why the argument in favour of watermaker for longer passages, rather than additional tankage.

This is not 'new' - I'm only repeating what other (much more experienced multihul sailors) have said in the past.

So, yeah, in principal, I agree with you - 20L per day is absurd. As my post up thread *actually* says, 4-5L/person/day is a more common estimate of minimalist consumption.

But if you're gonna take a freshwater shower every day......

You're gonna need a bigger boat..!!!!

[with much bigger tanks!]

[mikedefieslife]

Originally Posted by Buzzman

J
My comment was based on the obvious - that multihulls need to keep load weight to the minimum, or suffer a reduction in performance - so the recommendation of a couple of jerrys of 'emergency water' and a solar-PV-powered watermaker is the 'most appropriate' methodology for ocean-crossing multihulls. [IMHO]


YMMV

Multihulls like any boat just need to be kept within their design parameters. I think people mis-interpret what keeping it light means.

If the boat is designed to carry a (conservative) maximum of 2,000kg (It would will be higher on the modern multis with wide hulls) then keeping within that figure isn't going to cause any problems.

A mono of similar size might have a load carrying capability of 4,000kg. When saying keep things light, I'm guessing most people are talking about not loading a multihull as much as one might a mono. But surely that is obvious since you have a plaque telling you exactly how much your boat can carry.

After-all you're talking about boats designed to sail with anything from 4-8 people onboard. People are heavy.

[owly]

A multihull that is designed to carry 4000KG payload is a pretty substantial boat.... generally well in excess of 40'


A watermaker is a no brainer, I consider it non-negotiable on a small multihull. Take a look at the Searunner specs, as they are some of the most affordable on the used market. 1500 lbs (681kg) for the 31 and 2500 lbs (1136kg) for the 37. When you start adding up all the things that are payload, and that is everything that is not part of the boat itself, it adds up rapidly....... Just the human cargo and their personal gear for a crew of 2 would probably add up to between 600 and 700 lbs, and that doesn't include food and water, spares, dinghy, cooking and motor fuel spares, ground tackle tools, solar, wind, or other generating equipment, and batteries, refrigeration systems, etc, and countless other items we tend to forget. Catamarans tend to have close to double the payload, but when one gets into the big stuff (40+ feet LOA), they often have countless fixtures, conveniences and systems built in that gobble up what otherwise would be payload.


This thread is about cheap multis and projects....... Big and cheap do not go together. Up front cost may not be high, but ongoing costs escalate very rapidly with size... Everything is bigger and heavier and costs more. Sometimes one cannot afford to own a "cheap" boat, and that may be why it is "cheap".





I agree that a watermaker is an essential item on a multihull for reasons of weight if nothing else, but one has to look at what must support that watermaker also when adding up weight..... more solar and wind equipment, more wiring, more batteries.



I've always been a cost and weight and size reduction guy....... I've advocated using ice for energy storage for example, so you can make ice while the sun shines and reduce the battery needs, and even building a pedal powered watermaker, which some folks suggest would not work... the numbers say it will if designed intelligently.... Most of us need the exercise.


H.W.

[Buzzman]

Converting 1500lbs into "Real Units" I get 680kg.

So as adult average is around 100kg, almost 1/3 of your total payload is people.

And thinking about water tankage, say, to cross the Atlantic, even at 4L=4kg/per person/day that's around 160kg (bare bones minimum), so that's half the payload gone, right there.

Add other heavyweight items like the outboard(s) at say, 40kg (9.9HP LS Suzuki 4-stroke) - times 2 for a cat = 80kg, plus two fuel tanks of 25kg ea plus spare fuel of 25kg ea, and that's another 100kg in motors and fuel (again, small motor, minimal fuel supplies)

Add in a some chain, additional ground tackle and there's another 100kgs.

So you end up with around 100-150kg left in total for food, clothes, sails, electronics, batteries etc etc etc....

And that's your lot.

Sure, bigger boats than a Searunner 31 can carry more, but you need to be super conscious of the load you are putting into a multihull.

Hence why the minimalist tankage + lightweight watermaker makes sense. In the above scenario, instead of 160kg for tankage, you carry 1 x 20kg jerry full and an empty one to make water into, plus the 35kg watermaker. Max weight 75kg: i.e. less than half what the tankage weighed.

Providing you with an additional 75-80kg of carrying capacity.

That's a lot of freeze dried food......

[redneckrob]

Originally Posted by owly

20L....... absurd!! That's an ridiculous figure. If you need 20L a day, I suggest that you forget passage making and stick to short coastal hops...... I've never heard anybody else suggest anything even remotely approaching that figure. Watermakers are fairly new technology, but ocean crossing in small boats is not. A crew of 4 on a cat crossing the Pacific... say 3 weeks...... that's 1680 liters / kilos of water or close to 3700 lbs...Who has tankage or load capacity for that kind of water even on a monohull?



Normal practice is to do salt water bathing with a brief fresh rinse.......... someone needs to waste that much fresh water is no sailor. Many passage makers have budgeted for 1/10 that figure....... Water economy is not difficult. I suppose you are one of the "condo cat" crowd............ to each his own.



H.W.

Avoiding scurvy is a relatively new technology, that doesn't make those of us who ensure we get enough vitamin C somehow less than you or "no sailor". You want to do the minimalist thing, like you said, to each his own. But feel free to jettison the moral superiority complex, it's not becoming or justified.

[owly]

Originally Posted by Buzzman

Converting 1500lbs into "Real Units" I get 680kg.

So as adult average is around 100kg, almost 1/3 of your total payload is people.

And thinking about water tankage, say, to cross the Atlantic, even at 4L=4kg/per person/day that's around 160kg (bare bones minimum), so that's half the payload gone, right there.

Add other heavyweight items like the outboard(s) at say, 40kg (9.9HP LS Suzuki 4-stroke) - times 2 for a cat = 80kg, plus two fuel tanks of 25kg ea plus spare fuel of 25kg ea, and that's another 100kg in motors and fuel (again, small motor, minimal fuel supplies)

Add in a some chain, additional ground tackle and there's another 100kgs.

So you end up with around 100-150kg left in total for food, clothes, sails, electronics, batteries etc etc etc....

And that's your lot.

Sure, bigger boats than a Searunner 31 can carry more, but you need to be super conscious of the load you are putting into a multihull.

Hence why the minimalist tankage + lightweight watermaker makes sense. In the above scenario, instead of 160kg for tankage, you carry 1 x 20kg jerry full and an empty one to make water into, plus the 35kg watermaker. Max weight 75kg: i.e. less than half what the tankage weighed.

Providing you with an additional 75-80kg of carrying capacity.

That's a lot of freeze dried food......

My numbers are similar to yours..... though less optimistic... I see more weight in gear, per person when one looks at weather gear">foul weather gear, safety gear, bedding, etc, and of course one has to count galley stuff, radio / com / AIS / charts / chart plotter antennas / books and computers, dinghy, snorkels and masks and fins paddle boards, sailboards, bicycle, and countless other items large and small....everybody wants to bring something. Are you satisfied with "'bucket and chuckit" or do you need a Lavac and holding tank or a composting head? Is there a refrigeration system? How about the electrical to support it, and on and on and on....I know from backpacking how rapidly stuff adds up.....


In the example of the SR31, the total weight to WL is 7000 lbs..... 5500 empty.... What does it REALLY weigh "empty"? During the typical build, things are "beefed up" here and there, and it's liable to be overweight out the gate.... multiple coats of paint actually add significant weight, and then there is the dodger / bimini / hardtop....


In a perfect world we would build the boat of our dreams........and I've considered it. I'd like to have a 30' catamaran, but to achieve a "reasonable" load capacity even for long term solo live aboard sailing, I would have to increase the displacement, by either fattening the hulls or raising the freeboard / bridge deck height, and ideally build in infused foam sandwich for minimal weight. The materials cost is greater than ply construction, but every pound saved is a long term investment. It ultimately means a smaller lighter boat with a smaller less expensive rig, less maintenance cost at every point, lower fees and taxes, smaller engine / less horsepower needed to drive it, less fuel used.........

Where economy is concerned, small and light wins the day at every stage, and those higher initial costs to build light are amortized in cost savings rapidly. The cat wins out.... for example the KD 860 at only 8.6M or 28' as compared to the SR31 (9.45M), has a 1200 kg payload compared to the 681kg payload of the Searunner 31


To put this into perspective......... 72 kg per meter Loa for the trimaran versus 139.5 kg per Meter Loa for the catamaran.. That's a HUGE difference... the trimaran carries 51.6% of the payload per meter length over all........



Jump to the SR 37 and you have a 5000KG boat compared to 3180KG for the SR31 and you gain just 454 kg payload (1136kg).........or about the same as the 8.6L catamaran.


H.W.

[Buzzman]

Interestingly, the boat I wanted to build (but health issues have canned) was Ian Farrier's Command 10 (33'-4") tri, which Farrier's paperwork says has a design payload of 1200kg (2500kg tare - 3700kg waterline displacement), so that's pretty close to you 'lightweight' 30' cat.....and was designed way back in 1983!
If ever I win Lotto and can afford to have it built, I'd get it done in foam/glass, as it's a multi-chine design that would be easy enough to build, but I'd use the 'frames' as a male mould, and stiffen sheer panels with additional glass layers.
Probably need to get an NA to provide a glassing schedule....
But figure it could well end up a bit lighter than 2500kg.
Although, having said that, Farriers design spec is for 1/4" ply and only 6oz glass for waterproofing on the exterior, epoxy only on the inside, so that would probably actually be pretty light.
Be interesting to get someone to actually calc it out and compare....
Might need to use carbon to get it any appreciable amount lighter....

[owly]

Originally Posted by Buzzman

Interestingly, the boat I wanted to build (but health issues have canned) was Ian Farrier's Command 10 (33'-4") tri, which Farrier's paperwork says has a design payload of 1200kg (2500kg tare - 3700kg waterline displacement), so that's pretty close to you 'lightweight' 30' cat.....and was designed way back in 1983!
If ever I win Lotto and can afford to have it built, I'd get it done in foam/glass, as it's a multi-chine design that would be easy enough to build, but I'd use the 'frames' as a male mould, and stiffen sheer panels with additional glass layers.
Probably need to get an NA to provide a glassing schedule....
But figure it could well end up a bit lighter than 2500kg.
Although, having said that, Farriers design spec is for 1/4" ply and only 6oz glass for waterproofing on the exterior, epoxy only on the inside, so that would probably actually be pretty light.
Be interesting to get someone to actually calc it out and compare....
Might need to use carbon to get it any appreciable amount lighter....

I did a bit of Googling on the Command 10, as I am unfamiliar with it, and stumbled on a Command 10 that looks beautiful sitting in Bolder City Nevada offered at a marked down price of $30K........ Now that appears to be a real bargain!!


Listed with POP Yachts, it is currently available......... lots of pictures, and of course there is a Utube of it also. It appears to come with a trailer of sorts, said not to be suitable for long hauls said to be 13'6" wide on the trailer and 17' tall. Interstates are built for 16' clearances.



https://www.popyachts.com/trimaran-s...y-nevada-95442

https://www.youtube.com/watch?v=NjHWyPXZoJY

[purvisgs]

The farrier command 10 in Lake Mead, NV has been for sale for a long time, forum user multihuller has, I believe, seen it and his comments (a few pages back in this thread) were along the lines of: built a little heavy, may need a new minikeel due to water intrusion.

I'd rather bring the thread back on track by posting a few boats for sale than derail it further with more payload discussion, but I can't resist, here are my thoughts anyway. It should be pretty obvious to anyone that a catamaran (carrying the load with 2 hulls) has more payload than an "equivalent" tri, but the trade off, especially under 30ft.... is a MUCH more usable cabin on the small tri. My feeling and the general consensus seems to be that under 35ft, the tri, generally speaking has a much more usable, comfortable interior space, for the minimalist backpacker type cruising that could be expected on such a boat..therefore 26ft-30ft range I think the (well designed) minimilast tri..beats most "similar" cats.. Above ~35ft the catamaran interior becomes big enough that you can have standing headroom without too much of a boxy, high windage cabin, and still maintain adequate under bridgedeck clearance.. although some rare catamaran designs around ~30ft on up start to look pretty attractive as well. ex shutleworth, maine cat 30, Richard Woods, etc. Don't discount (especially in the tropics) the right open bridgedeck type cat in the smaller sizes.

The ~25ft UK red tri looks to me initially a little heavy built- in the forward photo it sure looks like a lot of extra timber. The larger boat by the same designer looks a lot more interesting. This boat was previously listed on ebay (completed listings search) for (perhaps) more photos.

The emergency type hand powered watermakers (ex Katidyn Survivor ~8lbs, I believe).. weigh a lot less than the 35kg estimate used above. I know there are powered choices that weigh less too... Look at some of the ocean crossings that have been made on small boats, such as hobie cats, 20ft custom beach cats, microtransat, small row boats, etc....and do some serious research on the gear choices they made. Of course the more successful & less risky of these crossings...especially in multihulls, were in custom boats or heavily modified boats that could handle the load and the conditions. But basically on anything of that size you'd have to approach everything with MUCH more of the extreme "ultralight" backpacker mentality.

Although the Searunner provides an easy comparison because Jim Brown listed the design payload more clearly than many others, it's unfair to compare a 70's, chine hull design to much more modern cats.


Skip Johnson 38 tri 26k Hawaii, has been for sale for awhile.. price has come down some I believe...
https://honolulu.craigslist.org/big/...950310133.html

Crowther 33/35 buccaneer tri still for sale in WA usa ~15k
https://seattle.craigslist.org/kit/b...959298994.html

Searunner 37 rough shape CA $2k. seller sent me a single old photo & didn't seem to know if it was polyester or epoxy..
https://orangecounty.craigslist.org/...959622656.html

Afterburner (52 Tennant racing cat in CA) still listed, $36.5k, It looks like the listed price came down $500 recently so it's probably still for sale...
https://orangecounty.craigslist.org/...918175991.html

There is a neglected marples cc 35 tri in WA usa (needs quite a bit of work- decks & new mini keel) that's not listed but most likely still for sale, 10k (may not be worth that imho) could perhaps track down & pm contact info if anyone seriousy interested.

Newick Cheers ("atlantic" proa) in France posted "seeking new skipper" to the Golden Oldies facebook group, no price, & I don't know how to link to the exact post but here is the group, date of post July 30: https://www.facebook.com/groups/GoldenOldiesMultihulls/

Trevor Banks 35 cat $12.5k (price has come down some) BC, Canada still for sale as far as I know
https://www.kijiji.ca/v-sailboat/del...ationFlag=true

Crowther twiggy 32 FL 25k
https://www.sailboatlistings.com/view/80633

Kantola 34/36 tri CA 18k, was for sale on Latitude 38 classifieds previously
https://www.popyachts.com/trimaran-s...ifornia-176547

[Buzzman]

I like the price on the Buccaneer 33/35, but it's clearly set up for raicng, as is the $25K Twiggy, but that's also an excellent price as a similar went up here in Oz for AUS$35K recently, so on the money.
According to contemporary reports, the Twiggy is a handful to sail fast, and can turtle relatively easily.
The Kantona 34 looks a good deal as well, although strictly speaking that's a cuddy cabin, not a full 'touring' cabin. Might be a bit cramped for anything but day sailing or weekend camping.