Owner Built Boats and Builders

[PaulBck]

Link to my web page, index


Designed and built in Tassie out of Hoop Pine plywood, one bloke , three years. A 32/ 35 foot cat would take longer but shows that a good looking ,good finish boat can be acheived in the backyard.

[owly]

Originally Posted by saltydog47

I did build my own boat , a Rival 41. Hull and deck built by Rival Bowman to Lloyd’s hull construction certificate.
This is very important for a home builder or home fitter outer .
To start with a recognised certified hull .
You are going to be putting a great deal of time and money into the project , you must safeguard your investment.
It took me 7 years , start to launch , working every minute I could .
All I can say is , you must be crazy to even think of doing this . I was . Would do it again NO .

I am a bit crazy...... always have been. I've also built a number of smaller boats over the years.... 3 actually. I will not step off into the abyss without having my ducks in a row. That means having worked out the construction process and how to do it efficiently. Choosing a boat that is not overly complex to build is an important consideration, and choosing a process to make it as easy as possible.


If I can find a boat that fills the bill for me at a cost that makes sense, that would be the preferable option. Again, take a look at the cats that are out there in the 30' +/- range, and you will see that only owner built boats are even worth considering... at least for someone who intends to do serious blue water world voyaging.



I began examining available monohulls, and soon came to the conclusion that I wanted a multihull. At first I was looking at trimarans, until I did the math, and realized that I couldn't even come close to a reasonable payload in a trimaran without going far larger than I wanted. The commercial builders abandoned that size range long ago, and the designers for home builders skew their priorities heavily toward performance at the expense of the kind of utility that matters to me. They also tend to compromise bridge deck clearance and windage because people want to stand up in the saloon..... an absurd expectation in a catamaran of that size..... resulting in abortions (to my eye).



H.W.

[owly]

Originally Posted by Noisykate

You might be interested in a friends blog - ‘Gleda’, a wharram Cat.
Website ‘thegledaproject.com’.
Actually sailed it.

Thanks for the link.........


H.W.

[lateral]

Originally Posted by Donald Bryden

After building my 45' monohull using plans drawn by a renowned Naval Architect, I offer this advice. If you are primarily a sailor, then scrap this idea. Find a boat that you can tolerate and go sailing. If your interest is in building, construction and creating, then continue on. It took me eleven years from plans to departure and during that time I sure got lonely for the sea.

+10 my similar experience as well.

[slmkr]

Regarding the difference between U and V hulls, it might be beneficial to consider that your buoyancy in a U hull will extend further to the beam ends than a V hull and thus increase your righting arm/moment. Also U hulls generally tend to extend that shape more towards the ends which would inhibit (somewhat) shape induced hobby horsing as well as increase load capacity. I don't know if this helps, but that is my understanding of Boatman's post. I could be wrong. Won't be the first time.


If you're building/designing your own you might want to think about a bow bulb, multi hulls have an appropriate length to beam ratio (of individual hulls- what the water sees) to take advantage of it. There was an Aussie or Kiwi designer that incorporated them in some of his designs. Can't remember his name.

[slmkr]

As far as the 50% beam on a cat, wasn't that to avoid interference of the bow wave of one hull interacting with the other? Within reason, more beam means more stability?

[wardred]

Try Woods Eclipse at Sailing Catamarans - Home the site has loads of useful build information

Boatsmith in Florida for Moulded parts of the same.
Property Maintenance Services for pictures of my 10 year build.
and search out swingcat for another built at the same time.
It sails loads better than the Prout 34 I had before.
Circumnavigating the UK this year fingers crossed for good weather.
Regards H.

[44'cruisingcat]

Originally Posted by Donald Bryden

After building my 45' monohull using plans drawn by a renowned Naval Architect, I offer this advice. If you are primarily a sailor, then scrap this idea. Find a boat that you can tolerate and go sailing. If your interest is in building, construction and creating, then continue on. It took me eleven years from plans to departure and during that time I sure got lonely for the sea.

44' cat, 3 years 11 months for me.

[Salmoneyes]

I typically do not chime in, but my journey to now started very similar to yours..

I actually started 20 years ago, looking at Formosa. I then had a chance to sail on a 45' cat. That changed everything.. It was all cat from then on.

I retired a couple years ago, and started putting my plan into motion. I found a Nautitech 475 that was in need of finishing. As I went down that rabbit hole, I learned a lot. There is so much more to cat ownership then one typically thinks about before they buy one.

My first hurdle, was the cost at the yard for its space. It took up two boat spaces and they were charging accordingly.
The second major hurdle was launching. Depending on the size you choose, a lot of "bargain" marinas, and harbors, can not accommodate the width of some cats.
Again, most marinas charge more for cat slips.

I realize you may be looking at narrower designs and may not be slipping your boat much or even a haul to, but those are issues that a lot of folks do not think of when looking at cats.

For what its worth, those same criteria you mention in the original post, were shared by us, and ultimately we went with a pilothouse. We bought a ship yard built steel boat that circumnavigated, and had a proven record of seaworthy design and build.

We would never have considered a boat to jump in and go. My background allowed me to be hands on with a total refit which allowed us to user that proven hull, and make the rest fit our needs and lifestyle, (with everything being run by an engineer for stamp of approval).

I agree a "non production boat forum" would be helpful. I frequently ask questions on the Boat Design forum regarding ideas for mods to our boat. Many of the members there are designers and builders, and for the most part you get good answers. I have a few favorite contributors who appreciate my project, and I get advice and even some engineering help which would have cost us normally. Our local engineer just reviews and approves, so it has saved us tons of money.
One piece of advice I would give, if you are designing, modifying or building your own boat, is getting professional help on your ideas. I found that some ideas sound great, even fully approvable, but once implemented, you realize it could be better, and you change it. If you are paying for the approval, you will quickly find the cost adds up. I would never advocate any mods to a boat without having a qualified person looking over your shoulder and helping with the math...

Just my 2 cents here....

[Dsanduril]

Originally Posted by owly

...It was a communication problem I think.... I've read and reread those words.... and I'm far from dense. I simply could not figure out what you were trying to say. Perhaps someone else could clarify it for me...

I'll take a swing. I think Boatman is alluding to the fact that most production cats have a 'U' shaped hull with nearly vertical sides. Some production boats may even have a bit of tumblehome (our Outremer does) or outward tilted hulls (Catana as an example). That means the beam at deck level and the beam at waterline are nearly identical.

In contrast, 'V' shape hulls like the Wharram and others have a considerable slant to the freeboard section of the hull. If you measure maximum beam at the deck (near/at the top of the 'V') you'll get a significantly different number than if you measure beam at the waterline.

I think Boatman's contention is that when you're talking about a length/beam ratio there is a difference in this value depending on 'U' (beam and 'waterline beam' nearly identical) or 'V' (beam and 'waterline beam' significantly different) shaped hulls.

[alansmith]

Owly, there is a catamaran up in Maine designed by Dick Newick. It is a performance cat about 42-43 foot. Very high bridge clearance. It is spartan design. You can see it in yachtworld. Been for sale forever. Older gentleman and his son used to sail it to the Bahama. Son got married and started his family. No more sailing partner. I recommend you give her a look. Her name is Pooka if I recall correctly. She makes my nipples hard. I ended up buying a trimaran down in sea of Cortez. If I wasn’t married I would have bought her and figured out a way to put a capsule beteeen the two decks. I just did u righteous find.

Good luck. Don’t build. Find and modify.

[owly]

Originally Posted by Dsanduril

I'll take a swing. I think Boatman is alluding to the fact that most production cats have a 'U' shaped hull with nearly vertical sides. Some production boats may even have a bit of tumblehome (our Outremer does) or outward tilted hulls (Catana as an example). That means the beam at deck level and the beam at waterline are nearly identical.

In contrast, 'V' shape hulls like the Wharram and others have a considerable slant to the freeboard section of the hull. If you measure maximum beam at the deck (near/at the top of the 'V') you'll get a significantly different number than if you measure beam at the waterline.

I think Boatman's contention is that when you're talking about a length/beam ratio there is a difference in this value depending on 'U' (beam and 'waterline beam' nearly identical) or 'V' (beam and 'waterline beam' significantly different) shaped hulls.

The question then is what beam are people talking about when they say 50%? Waterline beam is not generally a published figure.



H.W.

[owly]

Originally Posted by Salmoneyes

I typically do not chime in, but my journey to now started very similar to yours..

I actually started 20 years ago, looking at Formosa. I then had a chance to sail on a 45' cat. That changed everything.. It was all cat from then on.

I retired a couple years ago, and started putting my plan into motion. I found a Nautitech 475 that was in need of finishing. As I went down that rabbit hole, I learned a lot. There is so much more to cat ownership then one typically thinks about before they buy one.

My first hurdle, was the cost at the yard for its space. It took up two boat spaces and they were charging accordingly.
The second major hurdle was launching. Depending on the size you choose, a lot of "bargain" marinas, and harbors, can not accommodate the width of some cats.
Again, most marinas charge more for cat slips.

I realize you may be looking at narrower designs and may not be slipping your boat much or even a haul to, but those are issues that a lot of folks do not think of when looking at cats.

For what its worth, those same criteria you mention in the original post, were shared by us, and ultimately we went with a pilothouse. We bought a ship yard built steel boat that circumnavigated, and had a proven record of seaworthy design and build.

We would never have considered a boat to jump in and go. My background allowed me to be hands on with a total refit which allowed us to user that proven hull, and make the rest fit our needs and lifestyle, (with everything being run by an engineer for stamp of approval).

I agree a "non production boat forum" would be helpful. I frequently ask questions on the Boat Design forum regarding ideas for mods to our boat. Many of the members there are designers and builders, and for the most part you get good answers. I have a few favorite contributors who appreciate my project, and I get advice and even some engineering help which would have cost us normally. Our local engineer just reviews and approves, so it has saved us tons of money.
One piece of advice I would give, if you are designing, modifying or building your own boat, is getting professional help on your ideas. I found that some ideas sound great, even fully approvable, but once implemented, you realize it could be better, and you change it. If you are paying for the approval, you will quickly find the cost adds up. I would never advocate any mods to a boat without having a qualified person looking over your shoulder and helping with the math...

Just my 2 cents here....

I'm was aware of most of what you mention above, and no I'm not looking at a (relatively) narrower boat, but a far smaller boat. I don't have a family, and mostly sail solo. This will be a full time live aboard, with travel / voyaging being the objective. One thing you fail to mention is that there is generally little reason to slip a cat if it is occupied, nor would I choose to spend time in one of those "floating trailer parks"... Why would you when there are lovely quiet places to drop the hook? ........ as long as you don't wear out your welcome. A cat offers a decent comfortable platform when one is at anchor, that doesn't constantly sway back and forth like a monohull, and a view from inside, as well as in the expansive cockpit. living ashore, it is an expense due to slip or yard fees, otherwise much less so, in fact probably less expense as the incentive to take a slip is much less.... for the reasons I just mentioned. It potentially offers the option of doing hull maintenance between tides... where tides are sufficient, rather than hauling out or hiring a diver........ assuming it will "take the ground". These things can offset the higher costs you cite significantly. The shallow draft means access to places monohulls cannot generally go, and that can mean the ability to utilize shelter, not otherwise available in storm conditions.

I'm looking at the smallest boat that will meet my needs, not the largest that I could manage to afford, and in owner built boats this could be as small as 30'. That drives the costs down for absolutely everything. The focus here seems to be on boats in the 40-50 foot range........... for me such a boat is a money pit. Interestingly many people live on monohulls in the 30' range, but "nobody" lives on catamarans in that size range. I can sort of see why..... suitable boats simply do not exist for the most part. I've found a few, but monohulls are a dime a dozen.



H.W.

[boatman61]

There are liveaboard's cruising the Med in Catalac's, Heavenly Twins and some have transated these and also Iroquois.. Prouts like the Sirrocco 26 is another..
However they all suffer low bridgedeck clearance and limited headroom in the saloon.. reason is simple.. higher clearance and standing headroom would make the windage terrible on a boat so small.. it would go from being a Condomaran to a Bedsitamaran..
The average is between 4ft 6" and 5ft 3" in saloons of the above cats.. to meet your wants the bridgedeck clearance would need to be 3ft minimum and the saloon raised anywhere up to 18"+.
There was a French company made a 24ft cat that almost met these requirements but I think they gave up building them not long after the 1st year.. it was a dog ugly motorsailor.

[owly]

For me, lack of standing head room is a given.... Something I have to accept, lack of bridge deck clearance is something I will not accept.... A couple feet is adequate in that size cat......... if the bridge deck begins well aft. I would call the Prouts an almost trimaran ;-) The challenges of achieving bridge deck clearance and standing height is what is pushing cats over 40' It really doesn't work below that, and even on the 40+ footers they make the cabins far too large and add flybridges, creating an absurd amount of windage. The condo cats are motorsailors that won't sail close to the wind in light winds (not speaking from personal experience). The boats that interest me have a couple of feet of clearance and about 4'6" headroom in the saloon, which can be mitigated by having a couple of companionways with sliders..... The saloon is for sitting anyway. I very much liked what Richard Woods did with Mira....you saw the photo. It was open bridge deck, and an added low profile bridge deck cabin, makes this a very workable solution. There is room below for a good galley and lounge, and a good workshop area, a well as head and berths, and still a decent saloon above for lounging and keeping watch in shelter......... Compromise is the name of the game. Do you want a condo cat motorsailor, or a sailboat? What I want leans more toward the latter.


H.W.

Originally Posted by boatman61

There are liveaboard's cruising the Med in Catalac's, Heavenly Twins and some have transated these and also Iroquois.. Prouts like the Sirrocco 26 is another..
However they all suffer low bridgedeck clearance and limited headroom in the saloon.. reason is simple.. higher clearance and standing headroom would make the windage terrible on a boat so small.. it would go from being a Condomaran to a Bedsitamaran..
The average is between 4ft 6" and 5ft 3" in saloons of the above cats.. to meet your wants the bridgedeck clearance would need to be 3ft minimum and the saloon raised anywhere up to 18"+.
There was a French company made a 24ft cat that almost met these requirements but I think they gave up building them not long after the 1st year.. it was a dog ugly motorsailor.