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

Originally Posted by 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.

..

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?
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!

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

Regards
Richard

[robherc]

Originally Posted by Tad

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

[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.

Fully concur Manie.

Richard

[dskira]

Originally Posted by 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!

Tadd I was for almost two decades a boatbuilder, all sort of vessels. And I can say you are absolutly right.
Cheers
Daniel

[dskira]

Originally Posted by 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

We are fortunate that Tadd as a very good pencil, since is pencil gave job to good boatbuilder.
That said, don't dismiss to fast what' said, it is true.
You like it or not, if you don't beleive it, you are close to banckrupcy, or you work for charitable organisations.
Cheers
Daniel

[mydauphin]

Depends if you are the guy sanding the bottom....