Estimate Man Hours to build a yacht......

[AppleNation]

A bit of a broad question here...

How many man hours does it take to build a yacht?

And how does that change as the boat grows in size? i.e. does it take double the time to build 60 foot compared to 30 foot?

I know this is almost a how long is a piece of string question.... but what is your experience on long it takes.... and is your epxerience a hobby or professional build?

Thanks all.

[JeroenW]

The relation between man hours and length is definitely not linear.
To give a few examples, this guy is building a 39 foot trimaran and currently has built the two floats and is putting the main hull together now and is above 4000 hours already. He documented it nicely here:
http://www.fram.nl/workshop/figures/timeandcosts.htm

I came across another project where they built a steel 40 footer and he mentioned it to be close to 12 000 man hours.

It all depends on the amount of detail, experience, type of materials,...
I found that some designers are optimistic when they give an estimate of man hours needed to build.

I think best is to look for people who built the same design and check with them. Did you have anything particular in mind? On this forum the more details you give the more detailed your answer will be.
Generic question meets generic answer.

[AppleNation]

Thanks Jereon.

Just looking at building a 40-45 foot yacht..... and am trying to work out what the costs are going to be if I do some myself and sub-contract a lot of the work...

[JeroenW]

Well if you look at the site I specified there is some information there regarding cost as well.

[marshmat]

As a very rough first approximation, for a given class and quality of boat, build time and cost will go roughly hand-in-hand with displacement, ie. as the cube of the length.

This seems to be a reasonable approximation for boats of similar type and similar quality- for example, given a 30' and a 50' fishboat from the same port, intended for roughly similar use, it would be a reasonable guess that the 50' will be about 4.5 times heavier, 4.5 times more expensive, and take 4.5 times as many man-hours to build as the 30'.

Such comparisons break down when looking across classes. A 30' offshore luxury yacht might cost twice as much as a 30' coastal cruiser, which itself might be double or triple the price of a working fishboat of the same length. Systems, luxury, electronics, fancy teak interiors, racing carbon masts versus aluminum or wood, etc. all make an enormous difference in the price.

[JeroenW]

This is the link to the 12k manhour boat: http://www.joana.ca/_mgxroot/page_10734.html
But it is 53 foot actually.

[marshmat]

I've seen Joana on the hard a few times in the last few years. She's based just around the corner from my place. She's a gorgeous boat, appears solidly built, and looks to be very nicely outfitted for long-term cruising. I haven't seen the interior, but you can tell by looking at the hull, deck and rig that a lot of effort has gone into getting everything exactly right.

[Landlubber]

A 40 footer can be built in about 8 to 10 000 hours, such as a displacement yacht. This would be to WW standards and finished as such.

that would be for pro boatbuilder.

[AppleNation]

Thanks all.

I'm getting quotes of about 15k man hours for one-off boat... Ouch !

Landlubber - much prefer your estimate....

[StrandedMariner]

It always takes twice the amount of hours you think. :)

[whoosh]

well i,ve done 32 yachts
I can do a 40 footer in 4500 hrs, metal alloy with good woodwork,

[AppleNation]

Whoosh,
Wow. Great.

How is your composite work?

[whoosh]

Whoosh,
Wow. Great.

How is your composite work?

sorry i no NOTHING abt that sticky stuff

[Landlubber]

whoosh, that would have to be in production to do those short hours, but entirely believeble just the same, good on ya.

[AppleNation]

and how about if i already had female moulds for deck and hull ?

[AppleNation]

anyone?

thanks.

[TeddyDiver]

Not any major difference.. The hull is the easy part..
Most advantage in work hours you could get by simplifying the design.. However what's the point if you have such demands that you have to consider oneoff boat at all. Anyway that's usually the reason for oneoff production when you wan't something what's more demanding than a regular production boats can offer..

[apex1]

Not any major difference.. The hull is the easy part..
Most advantage in work hours you could get by simplifying the design.. However what's the point if you have such demands that you have to consider oneoff boat at all. Anyway that's usually the reason for oneoff production when you wan't something what's more demanding than a regular production boats can offer..

Exactly....

A 90ft newbuild I actually started here in Turkey ends up @ about 15lbs of boat built per manhour right out the door.:)
Hardchine, metal, easy construction but very high quality interior.....but....:?:

Built by professionals with some hundred years of experience accumulated!:idea:
Subcontractors who do nothing else than the same job every single day.
I guess if a amateur achieves 5lb of boat per hour he can call himself happy and busy.
just my two cent (€ cent of course)
Regards
Richard

[marshmat]

just my two cent (€ cent of course)We get it, Richard. Your money is strong, ours is not, and our friendly neighbours south of the 49th... well, theirs is different every time you check.

Your estimate of 5 pounds of boat per hour sounds reasonable for an amateur build. I haven't built my large boat yet- it's coming, eventually- but I've heard numerous reports of 10-tonners coming in at 4000 to 5000 hours, 5 lb/h would be 4400 hours for a 10 t (22000 lb) boat. If your pros are churning out boat at 15 pounds an hour, that's more like 1500 h for the same boat.... very fast indeed.

Most advantage in work hours you could get by simplifying the design.. However what's the point if you have such demands that you have to consider oneoff boat at all. Anyway that's usually the reason for oneoff production when you wan't something what's more demanding than a regular production boats can offer..
I'm getting the impression, TeddyDiver, that Apple might be thinking of building regular production boats. Simplifying the design- yes, for sure, that can speed things up. I'm still not entirely clear on what kind of boat he has in mind though.

[AppleNation]

Thanks guys.

Just to clarify I am building in composites... so please keep expereince relevant to that if possible.

Matt - yes plannig on doing more than one. How many depends on many many factors.

Thanks Again all.

[ecflyer]

I am currently building a 47' cold molded wood boat. I understand wood boats take the longest to build. I am a retired, very experienced carpenter by trade and so far have 4000 hours in the project. I have the hull, deck, pilot-house, stern, dingy davits, steel keel, skeg, interior partitions, cabin soles, exterior glassed & only needing final coat of paint, anchor locker complete, propane locker complete and life raft locker complete. I am currently installing the engine which is partially done. I expect to have my project completed in another 2000 - 2500 man hours. I have done all the work myself w/o any help from friends. Friends talk too much and get in the way. You should know that all my life I was a faster than average worker. Total time from start to finish will be approx 3.5 years. The final level of craftsmanship will exceed any factory production boat. I have some labor saving tips that will save you 1000's of man hours. If you do decide to build a wood boat, e-mail me and I'd be happy to help you out with some suggestions: ecflyer@netnet.net.
The relationship between size, cost and man hours is definitly not proportional. The larger the boat, the less it cost to produce and fewer man hours required to build per displacement ton. Let me appeal to your common sense. Let's compare a 35' boat to a 50' boat. The 50' boat is 42% longer, but does it take 42% more labor? Heck no! It does not even take 42% longer to build the hull & deck because experience has proven that once a worker is doing a particular job, it takes just a little bit longer to build something larger. Reason, set up time is the same and is part of the labor required to acomplish the task. My educated guess is that it takes 15% longer to build the 50' boat hull and deck. Now remember many of the boat building tasks do not change between a 35' & 50'er. You only have 1 engine to install, 1 water system to install, 1 stearing system to install, 1 plumbing system, 1 fuel system, 1 kitchen cooking system, 1 anchor system, etc.. The labor hours will be the same for these systems unless the larger boat installs fancier upgrades. Cost wise will be similar also unless the larger boat installs more equipment. One example would be adding a second head to the larger boat. But the plumbing system does not double in cost because we now have 2 toilets. Piping, tanks and pumps remaine the same so the increase in cost is just for the extra toilet. Most mfg's like to market their boats to the public as the larger the boat the greater the cost. The truth; however, is that they make a heck of a lot more profit on the bigger boat. Same issue applies to auto-makers. They make proportionally much more profit on the Lincoln than on the pinto. Some of the suppliers to the boat building industry have adopted similar pricing strategy. Shop around because they are ripping you off charging 42% more for parts on the larger boat. As a last resort, build the expensive part yourself, if you cannot purchase it at a reasonable price.

Have a Great Day !
ecflyer

[AppleNation]

Thanks Ecflyer.

So you are saying I should build myself a super yacht?

LOL

But seriously... Solid advice... thanks.

[apex1]

We get it, Richard. Your money is strong, ours is not, and our friendly neighbours south of the 49th... well, theirs is different every time you check.

Your estimate of 5 pounds of boat per hour sounds reasonable for an amateur build. I haven't built my large boat yet- it's coming, eventually- but I've heard numerous reports of 10-tonners coming in at 4000 to 5000 hours, 5 lb/h would be 4400 hours for a 10 t (22000 lb) boat. If your pros are churning out boat at 15 pounds an hour, that's more like 1500 h for the same boat.... very fast indeed.


I'm getting the impression, TeddyDiver, that Apple might be thinking of building regular production boats. Simplifying the design- yes, for sure, that can speed things up. I'm still not entirely clear on what kind of boat he has in mind though.

Take care Matt...my indication was related with a 90ft boat of 140000lbs!
To scale that number linear down misleads for several reasons.
I.e. plumbing and wiring is not a big difference done in 10ft or 30ft lenght.

I have a tiny little lobster boat 28ft in wood Epoxy under construction here, done for a friend. That ends up @ about 4lbs per manhour !!! Built by Pro´s!
see attachment
sorry very small picture but my Turkish Internet provider is terrible slow on uploading!

edit: Thank you ecflyer... very much on the spot !! You posted while I was uploading. And you made clear what I want to express.
I hope you enjoy the fruit of your task for as long as possible. I can really imagine what you are going through and adore you for that. I don´t have the time for such adventure, and if, I would fear it. Thanks.......

Regards
Richard

[apex1]

Just two more images, the right one shows a 6.5 meter launch around 4lbs per manhour too.

I hope I am not boring the audience by repeating some statements.

Regards
Richard

[TeddyDiver]

I hope I am not boring the audience by repeating some statements.
Statements?? Keep them coming if they are accompanied with pictures like that:D

[apex1]

Statements?? Keep them coming if they are accompanied with pictures like that:D

:?: Sorry, what did i miss?:?: Or whats wrong with the pictures:?:

Regards
Richard

[TeddyDiver]

Sorry.. I meant to be polite but as it happens every now and then.. I don't make myself clear..
Weil Sie uns diese schöne booten ziegen, finden ich unmöglich zu lesen was Sie schreiben.. :D
Hope I didn't make any major mistakes. It's a long time since writing in germany..

[apex1]

Sorry.. I meant to be polite but as it happens every now and then.. I don't make myself clear..
Weil Sie uns diese schöne booten ziegen, finden ich unmöglich zu lesen was Sie schreiben.. :D
Hope I didn't make any major mistakes. It's a long time since writing in germany..

I did not feel you were unpolite.

Ja, das geht so. :) Das Deutsch könnte besser sein, wie mein Englisch auch.:D

Regards
Richard

[Tad]

Boats do not change size linearly only. When length increases so does beam and hull depth (sheer to fairbody). Thus internal volume, displacement, and construction man hours, changes with the cube of the length. Double the length, beam, and depth, will increase construction hours 8 times! (2*2*2=8) See the Law of Mechanical Similitude for a reference.

3.5 pounds of finished boat (not displacement as that usually includes payload & liquids) per man hour is about average in a decent (yacht finish) yard. 4 pounds per hour for a cold-molded boat is good going. 5 pounds per man hour is flying. A medium finish 38' wooden (plank on frame)motoryacht in a good Maine yard is 4500 man hours. Maltese Falcon was 1.5 million man hours for 1200 tons of yacht. That's about 1.75 pounds per man hour, reflecting a very complex vessel. A Little Harbour 53 (Taiwan glass production) was about 3.7. A Hinckley Sou'wester 42 was about 9500 hrs or 4.1 pounds per man hour.

Comparing a 35' and a 50' yacht the man hours will be about double for similar finish. Man hours might be closer if you did not increase the beam or depth, but there are many more parts in a 50' than there are in a 35'. The 35' will have a beam of, say 12', and depth of 6'. The 50' will have a beam of 14' and depth of 7.5'. Thus we are comparing 35*12*6=2520 and 50*14*7.5=5250. These numbers are referred to by yacht designers as a "Cubic Number".

The usual 35' boat has interior plan A, a galley, simple saloon with opposing seats, a head, and a vee-berth. Fifty-footers are rarely arranged this way. In addition to the above the 50' will have a larger saloon and galley, one or two more sleeping cabins, another head or two, and vastly more complex systems. Look at the fresh water system alone. The 35' will have 2 sinks, 2 tanks, and a hand pump. The 50' will have 3-4 tanks, 3-4 sinks, a deck shower, a hot water circut, a pressure set plus a hand pump, and probably a watermaker with generator to run it!

[marshmat]

A good post, Tad.

It begs the question though- why, exactly, does the larger boat need to be more complicated? It's true that in practice, the larger boat generally is more complicated. But that doesn't mean it has to be.

It's often said (but I've never seen this backed up) that the hull accounts for something like 15% of the total build hours. The rest being propulsion, plumbing, rigging, interior finish, painting, etc., all of which will also add to the ongoing maintenance expenses.

While some folks like to have all the luxuries aboard a 50-footer that's worth $700k or so, I suspect quite a few people would be quite happy with a simpler, large boat if it could be had for the same price as a smaller boat with lots of luxury and complex systems.

[Tad]

Why....exactly.....

Well....it doesn't absolutely have to be more complicated. But there will always be more and larger parts involved. Certainly one can build a 35' or a 36' boat with virtually the same size and number of parts. But when you double the vessels size (as outlined above) by going from 35' to 50', there will be substantial changes.

In a cold-molded boat for instance, deck beams and floor timbers are going to be spaced roughly 15"-24", no matter the overall size of the boat. This means there will be 10-15 more deck beams and floor timbers to build for the 50'. Each of these beams/timbers must be designed, engineered, lofted, templated, the material must be acquired, machined, bonded, shaped, sealed, installed, and finished. That's might be 100+ additional hours right there.

Seemingly simple things like the anchor system get complex quickly. In a 35' one could pull the anchor by hand....easily. Few do as apparently "yachting" is required to be a no work undertaking. Many fairly small boats appear in our bay and the anchor is dropped and raised without anyone going out on the bow. Of course going out there would be unsafe! But on a 50' the anchor should be heavy, roughly 60+ pounds, and 3/8" chain is not light, thus we see windlass's. Then you need a good roller for this heavy gear, a big chain locker, a control system, and additional power to run the windlass...

Some large and simple designs are produced, George Buehler is one of the proponents of this. Unfortunately the end results are seen by the marketplace as lacking value. Part of this is that the vast majority of buyers have been sold a list of "features", rather than solid basics. The "features" are to differentiate your product from that of your competition, the more features, the more valuable the vessel....humbug!

[ecflyer]

Tadd,

No way does the man hours double from building a 35'er to a 50'er. I have 50 years experience in the construction industry and believe me I know what I speak of. Our land lubber architects believe about the same things as navel architects like Tadd. They must have attended the same schools. Sorry Tadd, but on the job experience beats out the books every time. Better stick to your pencil and drawing desk. If you think it takes more time to build thicker and longer beams on a deck, well that explains it all. Greater interior volumne adds approx 15% to build time and that's it. I was trying to get the truth out and convince everyone that it does not take 42% longer to build the larger 50' boat. Then you come along put out the BS that it takes 50% longer. Ha! Ha! Ha!

ecflyer

[marshmat]

I think I like the following guidelines:
- Build as big as possible, given the constraints of space, cost and ability to handle the boat
- Build as simple as possible, given the minimum standard of luxury you're comfortable with
- Build as rugged and durable as possible

I'd rather have a solid 50-footer with one head, no pressure water system and basic instrumentation and electronics, than a 35-footer with electric winches, pressurized hot and cold water, A/C, and those fancy Furuno or Raymarine multifunction screens that get redesigned every ten months or so. More space, less stuff that breaks and needs replacing.

[TeddyDiver]

No way does the man hours double from building a 35'er to a 50'er.
You right! They triple :D

[robherc]

Then you come along put out the BS that it takes 50% longer.
While we all appreciate your input, please don't disrespect other professionals for their opinions.

I, personally, don't believe that building a 50' should take much more than 125% the time as a 35', given similar internal structures. On the other hand, I can also see others' points that the 50' will be more marketable if it's more complex, and thus it takes significantly longer to build.
So, in the end, it comes down more to complexity, than to size, for what determines build time. Can we at least agree on that?

[apex1]

I think I like the following guidelines:
- Build as big as possible, given the constraints of space, cost and ability to handle the boat
- Build as simple as possible, given the minimum standard of luxury you're comfortable with
- Build as rugged and durable as possible

I'd rather have a solid 50-footer with one head, no pressure water system and basic instrumentation and electronics, than a 35-footer with electric winches, pressurized hot and cold water, A/C, and those fancy Furuno or Raymarine multifunction screens that get redesigned every ten months or so. More space, less stuff that breaks and needs replacing.

THAT IS IT !! Matt. you mentioned the main points.:)
The people usually are not very good in abandonment of any kind. So, if having a longer boat they like to have more beds bathrooms and the like.But if youre fine with a 50ft and translate the accommodation into say 75ft just to get a better speed and some elbowroom you have a win win situation. Having a lot more storage to spoil, a locker to hang your soaked rags, a wider icebox and the extra space for some 24 more beercase is not a big factor on your bill. The extra m² of hull plating and interior paneling, the 100 ft of additional piping and wiring, what´s that? Have a proper engine room, no motorbox and so on, but withstand the idea to build a cabin for mother in law!:D
In fact we redesigned a 70ft of 86000lbs to 88ft and 130000lbs, thats about 50% increased displ. and 25% increased length.
The cost ended up at additional 14,5% ! The time for construction differentiates by about 5% ! And it is a professional run boatyard that calculated it, they do´nt estimate.
Edit: cost added: 17% !...not 14,5%
Although TAD is right in general with the way he calculated, it is not always that easy.;)

@robherc:
So, in the end, it comes down more to complexity, than to size, for what determines build time. Can we at least agree on that?
At least I agree;)

Regards
Richard

[mydauphin]

Too many, I am 5 years into it.

[AppleNation]

Well from my perspective considering that I focus on weight and speed a 50' should not be much different to a 30'.

There will always only be one head etc... obviously there are some differences of scale...

I want to build a racer.... not cruiser.

Thanks.

[DGreenwood]

I think I like the following guidelines:
- Build as big as possible, given the constraints of space, cost and ability to handle the boat
- Build as simple as possible, given the minimum standard of luxury you're comfortable with
- Build as rugged and durable as possible

I'd rather have a solid 50-footer with one head, no pressure water system and basic instrumentation and electronics, than a 35-footer with electric winches, pressurized hot and cold water, A/C, and those fancy Furuno or Raymarine multifunction screens that get redesigned every ten months or so. More space, less stuff that breaks and needs replacing.

I can't tell you how accurate this assessment is. It is almost my Mantra.
A 50' boat with a 30' interior. Leave the forward 10' and the aft 10' empty. If it is a luxury you can live without, leave it! Now your talking about a sailors boat. Your life at sea will be much happier, cheaper and easier maintenance.

[marshmat]

The Dashews' FPB 83 comes to mind. I recall an article where Steve was being asked, basically, what the hell was he doing building an 83-foot motoryacht with the accommodations of a typical fat 55-footer.

His answer was that the two would be about equally complex to build and the added length (being not much more than hull structure) not all that much more expensive, but that by going longer, he could have more storage, a longer sea-riding length (thus faster and more comfortable), and didn't have to cram living space into the (uncomfortable) ends of the boat.

Now, I tend more towards a Buehler level of luxury (and cost) than a Dashew level. I think I'd start losing track of my gear in an FPB's hold! But there are similarities in the design philosophy of these two, and of several other designers who don't sell thousands of boats, but whose clients absolutely love them.

On the thread topic- so it looks like we have estimates ranging from 1.5 to 5 pounds an hour for typical boats and typical amateur or lazy professional builders, and possibly as much as 15 pounds of boat an hour for a really pro crew building a big, simple boat. That's a hell of a range, and the difficulty in getting a good estimate might explain why everyone says it's so hard to make money in boatbuilding....

[Manie B]

I couldn't agree more

I can't tell you how accurate this assessment is. It is almost my Mantra.
A 50' boat with a 30' interior. Leave the forward 10' and the aft 10' empty. If it is a luxury you can live without, leave it! Now your talking about a sailors boat. Your life at sea will be much happier, cheaper and easier maintenance.


and add to that - stay out of marina's and learn to anchor well as was indicated on some other post recently

and this is actually where i am going with my next build
simple plain boat

[JeroenW]

. That's a hell of a range, and the difficulty in getting a good estimate might explain why everyone says it's so hard to make money in boatbuilding....

When thinking about this I tried to make an analogy to the way cars are built and it seems to me that the parts being assembled at a car factory are made by a lot of sub contractors. And the parts are almost completely finished. While in ship building it seems to me that the amount of parts arriving ready to be finished are fewer.
Second observation is that in boatbuilding there's much less automation going on (due to amount of each model being made)?

Does this line of thought make any sense?

[apex1]

When thinking about this I tried to make an analogy to the way cars are built and it seems to me that the parts being assembled at a car factory are made by a lot of sub contractors. And the parts are almost completely finished. While in ship building it seems to me that the amount of parts arriving ready to be finished are fewer.
Second observation is that in boatbuilding there's much less automation going on (due to amount of each model being made)?

Does this line of thought make any sense?

Not if we talk about Boatyards / Shipyards ... but of course.. if we look at boatshops!;)

@ Applenation
Well from my perspective considering that I focus on weight and speed a 50' should not be much different to a 30'. a mighty statement for an absolute novice..... chapeau..
Yes.................... you focus on weight and speed... and thats why you are completely wrong here!
If there is already just a bit more than an empty shell in your design, how can you expect that there will be almost no difference in cost when you double the displacement?
Sometimes it is helpful to read what others tell you here. :D Complexity for example.
Regards
Richard

[robherc]

If you're just building a light, empty shell, then you're probably going to DECREASE your beam when you go from 30' to 50', which would make the 50' boat rock a little differently in beam waves, but take a bit less than the 67% more materials for if you keep the same beam.
If you raise the beam 67% too, then you're going to be paying quite a bit more for materials.

Any of the three ways, for just an empty shell (and yes, I know it's never really quite THAT simple) I'd guess that you'd still be putting in 20%-30% more time for the 67% more length...because some steps in the process actually do build time usage fairly linearly (or worse, exponentially). For instance, while I might be able to coax myself into longboarding one side of the 30' hull in a couple hours (and take a break after), I'd prob. get pretty discouraged & end up taking 2-3 breaks while boarding the same side of a 50' hull...phew! tired just thinking of all that sanding!

Don't take my word for anything though, I'm still working on my first build...rofl!

[Tad]

you're probably going to DECREASE your beam when you go from 30' to 50',

Why? Comparing apples and oranges is hopeless. You can only reasonably compare like with like. Reuel Parker can build a Terapin 36' in 2500 hours, Dudly Dix can build a Didi 38' in 3000 hours, Hans Christen Yachts spent 9000+ (production) hours on their 38' traditional....quite a spread...but they're different boats.

You can't compare cars with boats...here are comparative numbers.

car - 1.5 tonnes, 3000 parts, 20 hrs to assemble
battle tank - 65t, 14,000 parts, 5500 hrs
fighter aircraft - 10t, 30,000 parts, 57,000hrs
Boeing 777 - 250t, 100,000 parts, 50,000 hrs
nuclear sub - 7000t, 1 million parts, 8m hours

Below are some pictures of Long White Cloud, a Mobjack (LFH) 43' ketch cold-molded in NZ a few years back. She's about 40,000 pounds displacement and took about 14,000 man hours to build. This is what I would call medium yacht finish, nicely done but not over the top. Works out to almost 3 pounds per man hour, reflecting good quality construction (multi-layer planking) and extra effort to get the systems right. She is currently for sale at $570k USD.
28567

28568

28569

[apex1]

The Dashews' FPB 83 comes to mind. I recall an article where Steve was being asked, basically, what the hell was he doing building an 83-foot motoryacht with the accommodations of a typical fat 55-footer.

His answer was that the two would be about equally complex to build and the added length (being not much more than hull structure) not all that much more expensive, but that by going longer, he could have more storage, a longer sea-riding length (thus faster and more comfortable), and didn't have to cram living space into the (uncomfortable) ends of the boat.

Now, I tend more towards a Buehler level of luxury (and cost) than a Dashew level. I think I'd start losing track of my gear in an FPB's hold! But there are similarities in the design philosophy of these two, and of several other designers who don't sell thousands of boats, but whose clients absolutely love them.

..

Yepp............
and I am almost sure Dashews had a bit more than just a broad clue about the result of their efforts.;)

But let us talk about real life, compare these two boats:
http://www.balta.fr/Classe%2040.html
http://www.balta.fr/tocade50img.html

the first 40ft and 4,5 tons displ.
the second 50ft and 12 tons displ. :?:
both are build in wood Epoxy, both are racers, not cruisers, both born on the same drawing board.
I assume twice the time and cost to build the 50ft. Who disagrees?:rolleyes:
So, it is not enough to dash a few lines and figures and expect to receive a serious calculation. We are in boatbuilding where NOTHING is easy and nothing for free! In comparison calculating & building airplanes is a piece of cake!:cool:

And thanks to TAD! Some numbers are so nice to play with.

Regards
Richard

[robherc]

Why? Comparing apples and oranges is hopeless. You can only reasonably compare like with like. Reuel Parker can build a Terapin 36' in 2500 hours, Dudly Dix can build a Didi 38' in 3000 hours, Hans Christen Yachts spent 9000+ (production) hours on their 38' traditional....quite a spread...but they're different boats.

Actually, if I were designing a boat purely for speed, and I already had a displacement figure in mind, THEN (and only then) would the longer-hull, smaller-beam figure be apples-to-apples for me. That's the scenario I had in mind when I put that in there, since he said he's planning on building a stripped-down racing boat.

Realistically, I know that the longer hull + narrower beam = totally different boat...but then again, realistically I have never seen anyone build a boat bigger than a rowboat/canoe that was merely an empty hull.
So, please take my figures above with a realistic-sized grain of salt ;)

[Tad]

Ahhh.....I get it Rob...

Something along the lines of LFH's Restricted Sail Area Cruiser? She is LFH's idea (1931) of the ultimate performance from 1000 sq ft sail area. She came out 55' by 11'6", a double-ended ketch with the accommodation of a 35' boat.

In theory if the cubic number remains constant (thus displacement) the boat will require roughly the same amount of material and cost the same. So the short fat boat, at 35' * 12.5' * 6' = 2625, and the long skinny boat, 48' * 10' * 5.5' = 2640 are the same size and the same cost (man hours).

[WoodmanWoods]

Been build boats for 35 years..

smallest were fancy sailing dinghies...8 feet with varnished wooden spars etc... versus my buddy building all glass with rubber guards,, and his chop strand gun.. so 8 hours I guess compared to 80 hours.

A friend ran a major boat operation, they were in business 30+ eyars build 10,000s of boats and he told me the first of any model took 7 times as long as the 7th one. These builders were very accomplihed pros.

I built about 18 yachts of40 and 42 foot length, crusing sailboats they were molded hulls and decks. Very Fancy woodwork inside and out and all of them were custom. Varying lengthso fbunks, moved bulkheads, extended cabins etc. They took approximately 7000 hours and were heavy at 18000 +/-. I built 2 similar 52 footers that were 44,000 pounds that took 12,000 hours.

We built cold molded, one off glass, scrimpt method glass, aluminium etc..

The largest boat I have done is 143+ feet and took about 200,000 man hours.

I find some house builders here that think there is a similarity and there is not I have also built homes, both reasonable ones and ones with million dollar plus rooms for movie theaters etc.

Fit and finish matters.

You can price and figure a boat by the pound witha track record that is viable and experienced but remember weight costs both ways.

The America's cup racing boats are very light but VERY expensive as it costs a tremendous amount of money to remove that last 6 ounces..

thanks

[Tad]

woody.....

Yes, those numbers fall right in with what I stated earlier. Your 42's are right at 2.6 pounds/man hour, and the 52's are at 3.6 lbs/mh. Bigger boats are often more complex due to added systems, multiple tanks, multiple voltages, etc. But they can also be built of bigger pieces, thus adding weight quicker.

Antonisa, built at Hodgdon's, is 365,000 pounds and required roughly 220,000 man hours. That's 1.65 pounds/mh and again reflects construction to the very highest standards with huge complexity in methods, finish, and systems.

[WoodmanWoods]

Yes Tad, I worked around some of the the highest fit and finish and the hourly rate by "pros" was low in hours.. You can sure catch up quickly with a
75,000 keel. But some stated that pros build at 6 pounds or so per hour.

I have been speaking with a home builder that feels he can build himself and save lots of money. He has no plans, seat of pants, lots of changes, no insight to weight reports, schematics, etc..

The old "Sell a dream and build a nightmare."

[Landlubber]

"Sell a dream and build a nightmare."

emmm, methinks you are very close to being right there mate....I have seen some beautiful home built boats, but the majority are certainly not like that.

I am "trying" to turn a pigs ear into a silk purse for one poor fello currently, no hope of course, but he refused to sell it and now has spent on $400k on a boat that would be lucky to fetch 100 (if he sold it to a blind man)....I have told him to STOP spending money, but he insists that he has to as he has so much "invested" as it is....very sad.

[Manie B]

a home builder that feels he can build himself and save lots of money. He has no plans, seat of pants, lots of changes, no insight

and the saddest part is that most of them live by the attitude

Go Big or Go Home

why they CANNOT start small and get to grips with things beats me

now that my tiny little microcruiser is taking shape i get told regularly by many visitors that why am i not building a 40ft cat :rolleyes:

[marshmat]

You can always add expensive gear and gadgets to a sound, sturdy hull later on, as needs and finances demand.

It is awfully hard to retrofit a sound, sturdy hull to a collection of expensive gear and gadgets.

Skimping on the basic essentials rarely pays any dividends.....

[rambo!]

This has been a very interesting thread to follow.
For a pro builder a mh count has to be essential to be able to give a quote to the customer.
For an amature/one off builder a lot of other things has to be taken into account, skill, pleasure, visions etc.

Most homebuilders will probably undersestimate the mh/lbs and still be happy, a pro builder can not afford to underestimate.

A Swan yacht will probaly have more mh/lbs than a Bennetau...but if owner of any brand is happy with the boat...who cares.

A homebuilder will probably spend more mh´s to save and effectivly use expensive material than a pro bilder with high running cost of labor.

But anyway the thread has been of great interest.

[Manie B]

Great thread - and just to add a bit more - guys that are buying plans - in general add 50 % to the quoted hours.
This is the conclusion that i came to after reading MANY build stories on the net, and if you are going to work with expensive epoxy and kevlar / carbon laminations - these take time to do carefully and properly.

[apex1]

Fully concur Manie.

Richard