Origami steel yacht construction

[Guest62110524]

bow on the boat is , politely put, a mess

[Brent Swain]

Several were passed for charter by Transport Canada surveyors. They said they were familiar with the method, and have no problem with it.
The origamiboats site is very active, unlike origamimagic.
These aluminium boats, and plans for them, were beyond the price range of too many, unlike my steel hulls.
I find putting the longitudinals in while the plate is flat on the ground is far simpler. As you already mentioned , it doesn't take much time at all to put framing in, far less time than fitting plate to an existing frame

[dskira]

Originally Posted by Brent Swain

Several were passed for charter by Transport Canada surveyors. They said they were familiar with the method, and have no problem with it.
The origamiboats site is very active, unlike origamimagic.
These aluminium boats, and plans for them, were beyond the price range of too many, unlike my steel hulls.
I find putting the longitudinals in while the plate is flat on the ground is far simpler. As you already mentioned , it doesn't take much time at all to put framing in, far less time than fitting plate to an existing frame

This is what Welder/fitter said about the survey:

On certifying a boat for marine charter in Canada, based on registered tonnage, area of operation and passenger capacity, prior to 1998-99, inspections were rarely performed for small vessel certification, it was a simple matter of making application & submitting construction info which is supplied by, both, owner, and builder or designer. Post 1998-99, surveys are conducted by independant marine surveyors, acting on behalf of Marine Safety. This information & the application forms can be found here: http://www.tc.gc.ca/eng/marinesafety

Because of a lack of physical inspections, combined with authorized exemptions, there are many "certified" vessels in Canada which are less than seaworthy. An example of this is evidenced by the Canadian Transportation Safety Board's report on the Cap Rouge, a fishing vessel that had modificatons which resulted in a loss of stability. The owner of the vessel, a family friend, lost his wife & children when the boat capsized. There was no required inspection for the modifications. Ben, the owner, has been pressing for changes to this very flawed system, since his tragic loss.

Because there is a lack of standards regarding the construction of Brent's design, there may not be two that share the same displacement, stability calculations, etc. . One has only to view the "origamiboats" site, on Yahoo, to realize that insulation, interior fittings, even mast/rig choice/composition, is left to the owner/builder, with suggestions/recommendations made by Brent & the other builders, many of whom are first-time builders, themselves.

I will not adverstise that as a plus for my boats
Daniel

[LyndonJ]

Its also apparent that boats built by Brent are different to boats built by Evan Shaler which are different to boats built by reputable yards. Those yards often add full class regulation framing to Brents hull shape. Not the same boat at all, and it would even pass class survey on construction.

Trouble is Brent never separates out specific vessels, builds, sizes or framing absent or present.

[peter radclyffe]

quote
by B S
Many of my hulls have saved their owners from the disasters which would have resulted in most other cruising boats out there.

[Tad]

Originally Posted by Brent Swain

Several were passed for charter by Transport Canada surveyors. They said they were familiar with the method, and have no problem with it.

Elsewhere you state an aluminum 53' was certified by TC for charter work. One is not several. I understand this is not your design. The name of the boat or the owner will enable me to substantiate this claim.

What a TC inspector said matters not at all....either the boat has a certificate...or it doesn't.....

Assisting owner's in achieving TC certification of small passenger vessels is part of what I do for a living. Canada's bureaucracy knows no bounds....currently this is an immensely complex and frustrating (for owners and myself) process. In the past, as stated above, things were different and far more lax than at present. Each new accident sees another wave of new regulations......

The construction of a prospective small passenger vessel must be submitted to TC, in the form of standard drawings, for checking and approval by a TC naval architect.....they only have a few (3 in BC) so it takes many months......

Today I have on my desk a set of TC approved construction drawings for a Bruce Roberts designed R 532, a 55' steel radius chine sloop. There are 10 construction drawings, each covered in red stamps and a notation....."Approved for structure only: for operation on restricted Home Trade III voyages; limited to a maximum significant wave height of 2m; and a maximum wind force of Beauford 6, or less."

Not exactly a wonderful endorsement of the structure....as it happens this particular boat is substantially overbuilt compared to BR's construction plan....I may be going back to re-draw the "as built" construction to increase her weather restrictions.

Beyond this I have just spent 10 days doing an additional 12 drawings showing the "as built" arrangement and systems. I have another several days into a complete stability booklet which includes a TC witnessed Inclining Experiment. The documentation, required equipment (alarms, lifesaving, firefighting, electronics, etc) crew certification, manning requirements, etc.....are immensely expensive and time consuming.....The owner of the BR532 above is currently in Vancouver getting a new multi-thousand $ engine room door fitted...because it's required and approved......now I need to invent a wind heeling load to add to the stability curve....endless fun

[Brent Swain]

A multi thousand dollar engine room door would put most of my clients on the beach for life. So you say that is the way to spend ones life , grounded, for want of a multi thousand dollar engine door? And all the other crap the government is using as excuses to deny the not so rich the freedom they seek, and force them all into cookie cutter, urban lives??
Do you suggest they should be dense enough, or apathetic enough to buy that elitist ********?
Don't bet on it!

[SheetWise]

This is degenerating into a pissing contest. Please stop.

It's like a man on land building in a hundred year flood plane with a 56.7 percent chance that he'll survive his actuarial life without issue ...

There is no 100% guarantee, level of craftsmanship, or level of design. Please admit the trade-offs you accept and move on.

This could be a really interesting discussion if the many of you would admit that the other has made serious points which the others clients chose to override. If that's not the case, then defend the charge.

I'm getting lost here. Define your disagreement in friendly terms. I think I know what it is, but I would rather hear it from you.

[MikeJohns]

Originally Posted by SheetWise

............

There is no 100% guarantee, level of craftsmanship, or level of design. Please admit the trade-offs you accept and move on.............
I'm getting lost here. Define your disagreement in friendly terms. I think I know what it is, but I would rather hear it from you.

I think you are getting lost too. Lets see if I can frame it concisely

There are very good guides to building and framing a boat, Brent doesn't hold to them. He also doesn’t respect people who do.

His view has always been that there are two schools of thought, On one hand there's historical observation, the engineers naval architects metallurgists and class societies. On the other hand there’s Brent with some odd beliefs he made up.

Those odd beliefs have been totally sunk in the last few days on the transverse frames thread but everyone knew that for years. The battle has been to convince Brent that he deserves accolade for developing his darted foldup plate method.

But not his framing approach, which frankly is bordering on inadequacy for his 36 footers. The same approach on a 60 footer would be a disaster.

[SheetWise]

Originally Posted by MikeJohns

The battle has been to convince Brent that he deserves accolade for developing his darted foldup plate method. But not his framing approach, which frankly is bordering on inadequacy for his 36 footers. The same approach on a 60 footer would be a disaster.

Thank you. If I understand correctly, the "darted foldup plate method" does introduce a geometry that adds rigidness. Wouldn't it then be correct to determine how the rigidness of that geometry is affected by choice of plate material and whether or not the geometry creates an efficient hull?

Certainly there has to be a point where the choice of plate material negates the need for framing -- are you simply saying that what strength he has added by geometry has not been compensated by his choice of material? Or are you saying that what has been added by geometry and natural stiffness is overrated?

[MikeJohns]

It might save some time if you read this thread from somewhere around here :

Transverse frame calculation

The shape has too great a radius relative to the thickness so it has a very minimal role to play. Relatively thin Shells buckle too easily and the framing is so slender it's not significant either. Brent unfortunately thought it had added strength by always remaining in compression.


Anyway read that thread first.

[Brent Swain]

Originally Posted by LyndonJ

Its also apparent that boats built by Brent are different to boats built by Evan Shaler which are different to boats built by reputable yards. Those yards often add full class regulation framing to Brents hull shape. Not the same boat at all, and it would even pass class survey on construction.

Trouble is Brent never separates out specific vessels, builds, sizes or framing absent or present.

In 1983, a client went to a big yard for a quote on a bare 31 ft hull and decks. The quote $80,000 . I built the shell. Cost? Less than $3500.
Does that answer more questions?
The boat was Eclectus ,built for John and Pam who worked for a computer firm. They sailed her from BC to Mexico , down the coast of central America, thru the Panama, up the east coast to Nova Scotia, back to the Carribean, then across to Ireland and England, where they stayed. No problems.

[Brent Swain]

Originally Posted by SheetWise

Thank you. If I understand correctly, the "darted foldup plate method" does introduce a geometry that adds rigidness. Wouldn't it then be correct to determine how the rigidness of that geometry is affected by choice of plate material and whether or not the geometry creates an efficient hull?

Certainly there has to be a point where the choice of plate material negates the need for framing -- are you simply saying that what strength he has added by geometry has not been compensated by his choice of material? Or are you saying that what has been added by geometry and natural stiffness is overrated?

Make your self a sheet metal model from the pattern shown. The structural geometry is self evident.

[Brent Swain]

Some one suggested that I advocate 1/4 inch plate for a 31 footer, a prime example of the lies people put in my mouth so they will have something to argue against.
My 31s are 3/16th plate . I'd prefer 4mm for the 31 if it was available. Ganley uses 3/16 plate for his very successful 30 ft Snowbird.

[Brent Swain]

Originally Posted by MikeJohns

It might save some time if you read this thread from somewhere around here :

Transverse frame calculation

The shape has too great a radius relative to the thickness so it has a very minimal role to play. Relatively thin Shells buckle too easily and the framing is so slender it's not significant either. Brent unfortunately thought it had added strength by always remaining in compression.


Anyway read that thread first.

Experience of a couple of hundred boats has proven this idea dead wrong, repeatedly, over the last 30 years.
That is why you want to take calculations, which have been proven wrong so many times, and use them to discredit what has been well proven in the real world, sorta like calculating the ultimate stability of a boat, without taking into consideration the huge effect of the shape and buoyancy of the cabin and wheelhouse on ultimate stability.