tall stories in short supply

You could be on to something there Alan. Longliner is 6 foot 8 and 20 20 is only a short 6 foot 5 inches. You dont hear Longliner complaining.

Hes not a relative of Wilma's is he?

 

POIDA, ALAN, ERIK, WIL et al

Thank you all. Alan has raised some good points. As have many of you. Perhaps these points might be worth considering.

ALAN said
…I don't understand your approach to design. There is one single fundamental requirement, that the living quarters be sufficiently high enough. This does not mean wider, nor that there be larger lockers (are your wine bottles larger? Your pots and pans? Your charts? Your engine, fuel tanks, water tanks, generator, sails, ground tackle, etc..

OK, thanks for the chance to start on the details. A bunk needs to be substantially longer (and wider) – this impacts on the cabin size and therefore the position of frames and bulkheads. If the aft cabin bulkhead and ensuite head is just moved forward, then what of the engine placement?
Lockers do need to be deeper and wider – jackets alone can be a foot wider, bib and brace wets longer, shoes elephantine! – so passageways get smaller?
The passageways do need to be wider for centre of gravity, seats do need to be wider and a little higher.
Bench heights, sinks, basins, heads etc all do need to be higher and deeper (please just trust me on this)
Shower heads and taps need to be higher (don’t laugh, try having a shower that can’t point any higher than your chest, in a stall so narrow you can’t bend to get your head wet!)
Portholes need to be shifted for eye level vision, Ceiling height and window frames need to be repositioned in the pilot house to ensure clear visibility.
Booms do need to be a little higher, this affects centre of effort etc
Side decks do need to be wider (big feet, top heavy, higher centre of gravity)
These things do need to be understood, if you try to squeeze it all into a space meant for something smaller, something surely has to give? What gives and what is the flow on effect?

ALAN said
…..So it strikes me as a bit odd that nowhere can be found a designer who could modify (yes, I say modify, and if 2020 disagrees with the term, he must know enough about design that the last thing he needs is help designing the boat).

My point is only that surely there must be designer(s) familiar with (any) design ramifications and that if anyone knows of them, I’d be very pleased to find them.

So I'm assuming he doesn't know a whole lot about boat design.

Quite right, a little knowledge is dangerous. A lot of experience in what doesn’t work is only a starting point. I’m also prepared to accord the same ‘peter principle’ to designers.

It will be difficult to assist anyone who will argue with wisdom while professing to need it supplied.

Argue? I’m sorry if my answers seem that way. I do however question the singularity of wisdom. (and I’m not suggesting post modern relativism has a place in engineering). Even here at this forum, there are wonderful disagreements amongst those who clearly know more than I do.


Will said
…I disagree to some extent that just because you're tall makes you more prone to falling over. Yes your CG is somewhat higher
I can see that you might require a little more room at foot level, in order to spread your feet apart and things such as this,

Yep you’ve made the point, just a little extra general width, but where does it come from if not scaled up?


Erik,
In my experience you should regard tall people as scaled up "normal" people. Humans are remarkably proportional heightwise. A small deviation from the normal proportions will make arms or legs look extremely long or short. The living quarters for a tall person should be "scaled up" to remain comfortable. In my experience from backpacking in mountains, the consumption of water and food is proportional to body weight. Weight and volume of clothes etc. are also proportional to body size. You really need to scale up the living quarters (but as has been pointed out, not neccesserily everything else.)

ERIK, you mentioned earlier you design in this field. Are there any texts you might point me to? You seem to have an understanding of many of the issues.


Poida
It is easy to say "size it up" but how does that effect the boats performance and does that require tank tests and if a designer does design you a special one off, their contracts probably have a disclaimer so if you do end up with a lemon, you have to wear it.

POIDA you’ve got it nicely. Ultimately my questions here are in my quest to arrive at a seaworthy craft, that fits me and mine; that’s a pleasure to sail with her own lines. The unknowns shouldn’t be disregarded and changes to the norm in design parameters can, as we all know, have a massive affect on a boats performance and handling capabilities. I would prefer to avoid any avoidable mistakes through the knowledge and experience of others.

Thank you all for your comments so far, this really is a tremendous forum.

 

buggered up the italics on the last post,

sorry if it's a hash to read.

 

2020, you mention a few details--- about a specific ship? The stays'l schooner? Let's have at the interior plans and see what, firstly, could be done to provide longer berths.
As you know, some boats have side deck passages 3 ft wide, and some 4 ft, and some 2 ft. It isn't as if all side decks are even close to being similar in width, nor are a lot of them the same width the whole way forward. Is the schooner design too narrow on the side decks?
Pictures are needed.

A.

 

Gday Alan, thank you again for taking such interest. Firstly on an earlier point of yours; the interior construction is not a problem per se. You are quite right in pointing out that building benches, etc should cause no concern. It doesn't. Much of the internal fit out will take place as we go, with an (initial) liberal use of badly cut & fitted marine ply (by me), until we can get back up to Thailand / Burma /Myanmar for a decent fitout. This will laso allow enough time to 'fiddle' internally.
The side decks are only an issue in this particular vessel because the designer doesn't want to change the coachroof. All quite understandable.
Again, this illustrates one of the challenges we have discovered. That changing one thing inevitably affects another. So 'modifying' almost always has ramifications. Not a bad thing in itself at all, but again, I worry about someone elses learning curve.
cheers
2020

 

:?: :?:

I really must be missing something here - still!
I can't fault anything you've said 2020. But I'm truly at a loss to understand why you so far been unable to find a designer who can meet your requirements. Custom boat design - not stock plans design - is all about meeting the specific needs of the person you're working for. Each and every boat is different - that's what makes it interesting.
Normally, you'd sit down in consultation with the designer and list all of the things you need / want / like / dislike etc. This is the start of the 'design spiral'. Out of this comes some preliminary sketches, which are honed until they meet the design brief.
One of these steps might suggest that - because you're too bloody big - you need a bigger boat in order to fit everything in. The alternative is to chop some thing(s) out until the boat can be brought back to a manageable size. It would be a mistake to look at a 65 foot boat that you like and say to a designer - right I want a 65' boat just like that, only I want everything inside to be bigger. Unless your names Dr.Who, it quite obviously can't be done.
Other than that, I see absolutely nothing complicated about the boat, as you've described it, from a design point of view.

 

2020,
I would say that I'm generalist and systems engineer, and expert in other fields than ergonomics. Ergonomics is however essential where I work, and we have specialists for this as well. So I don't really need books in this field; I have people to ask. When I get back to the office I will check with them if there is any good literature to recommend. I know that there are MIL standards, but they are not enjoyable to read.
Erik

 

2020 Looks like you’ve been given lots of good advice but I’ll add a ramble here.

Larger boats are a lot more forgiving to these sorts of changes. The trick is to accommodate people at the Galley, Bathrooms, and Wheelhouse with ample headroom and reasonable ergonomics but if you want a range of heights there will be some compromises. On a big boat it’s easy to drop the cabin sole to vary headroom, Bunks are also easy to extend with very minor juggling.

Best to compromise that you will stoop, say in a fore-aft access way, but have areas of ample headroom where it counts. Crouching headroom is important here too in machinery spaces. Above decks is easier.

However as the client you do need to be specific on interior dimensions that you consider really important. Then the designer (who should be an experienced sailor) will try and get you to accept some compromises.

It’s easy to design for tall folk but a mistake to design solely for this, it is more of a problem to still allow good access for the shorter folk and children who will be aboard at times. If it’s a blue water boat windows can be a bugbear as it’s hard to get good viewing angles for all sizes through small windows, then for example an internal helm may need a slide out lockable platform. Interior helm stations are very important ergonomically when standing and need designing with care so that all aboard can safely con the vessel.

I scale a CAD model human on the clients vital statistics. When a couple, I have one for him and one for her and I put both models in helm positions doorways bathrooms Galley, bunks etc and look at elbow and eye heights ample leg room etc. This works very well with 3d CAD packages when squeezing interiors into confined spaces.

So much easier now than the scale mannequins we used to use in mock-ups.

If you want, email me engden@aapt.net.au or mikejohnseng@yahoo.com. I did engineering design on a similar vessel recently and have some stock designs myself.

 

All good points, Mike. I think the dropping of the cabin sole is the most easily changed item. Stability increases, the deck (with all those things attached--- dinghy, lifeboat, skylights, ventilators, and so forth) remains the same.
Floor space below DECREASES at the margins, by as much as a foot. Luckily, this is exactly where seats, berths, lockers, counters, and so forth are found.
A steel 65 ft boat can handle this loss of floor space more easily than a smaller boat. I believe the lowered sole to gain needed height, and a rearrangement to avoid standing requirements at the margins, along with fitting in some longer berths, would make sense.


Alan

 

Sirs,

Still on subject. Other than already stated alternatives, how would you go about adjusting headroom up in a 26-30 foot steel auxillary cruiser, say a Robert's Tom Thumb?

Thanks.

Tim

 

I am a little confused as to what this thread is all about. I am 5.11 thats not big, bit small really. 2020 is 6 inches bigger than me? thats about the size of a mans hand.

2020 must have all his life had trouble buying shoes, suits, cars, etc Why this new found difficulty over boats. Words like elephantine are misleading ,we are talkin 6 inches bigger than me ,--probably 5 inches bigger than most avarage person today.

2020 will have to buy a bigger boat as he does when he buys shoes.

My last boat a Roberts measured out at 62 feet ,it had a kingsize four poster in the aft stateroom. The lower lounge had 8 foot cielings. The step down galley had possibly 10 feet.

Bigger boat more space , this has been suggested more than the once.

 

Frosty
Yes were all pretty well the same size really but 6 inches to eye height can make a picture window for a tall person into an overhead skylight for a shorter one, apart from that sort of issue I can't see why any designer wouldn't happily make a few simple changes to accommodate a lofty client.

A lot harder since the cabin tops have to go up, probably better to accept some limited standing room with say a raised 3-4 ft squares in the cabin top if retrofitting the vessel.
If building from scratch just add 6" to the topsides and compensate for the raised COG by increasing the ballast cog draft by a few inches, but this needs running past the designer or an engineer as you may need a small boost in the frame scantlings also, usually it is a very simple and a minor boost to the frame floor scantlings will usually do the trick.

 

I can't imagine much being added to a Tom Thumb, maybe two inches. The cabin top could be made from cored glass, ending up 5/8" thick or so(but with no frames), with slightly more crown if need be, ending up no more than an inch taller. Even then, I wouldn't do it if the another larger boat had enough height. The supposition would have to be that I was really tall, the boat was complete except for the house roof, and I was being given the almost-completed boat by a confused philanthropist.
Smaller boats lose a lot of their visual appeal when made taller. I never liked the Flicka for that reason. Imagine 100k for a short, stocky boat with 6 ft of headroom, compared to 100k for a longer, bigger, more graceful, faster and more weatherly boat with the same headroom.
Conversely, I believe some architects go to extremes to get the right look, designing 28 ft boats with 5 1/2 ft of headroom when 6 ft could have been had without great loss of classic appeal. They back up their shortness of height by saying things like "there is no activity that demands one should have to stand..."
Well, there is a huge difference between a slight crouch and standing up fully.
I think designers forget they are designing a human dwelling. I think they sometimes carry the low-roof thing a bit too far and justify it by whatever salty anecdote or historical nonsense is at their disposal.
Getting standing headroom is like breaking through to another dimension, like the difference between being pregnant and not.


A.

 

I worked in a leather shop where I had to hunch to get from one work area to another. In addition to repeatedly cracking my head on a beam, corner of ductwork, and exposed incandecent light bulb, the crouching caused extreeme back & neck pain.

A boat broker tried the "you do not need standing headroom" ploy on me once. Felt like installing a 5.5' drop ceiling throughout his home.

Tim

 

I must admit, on the one hand I would have thought (hoped) that you would not have any trouble finding a naval architect wiling and able to meet your every whim, on the other hand does 5 inches really make that much difference to your life? Well, Frosty's missus says so
My wife is the main user of our fridge. She is 5'4". Sometimes I help myself to a beer from said fridge. I am 5'11". I don't find it ergonomically hard to use. We sit on the same sofa, use the same loo, use the same tele remote (when she lets me!). Our sie difference makes no difference. Is 6'5" really so big that you need to supersize everything? Cos its sure gonna cost. But then the customer is always right, and if that';s what you want, that's what you should get.

PS Frosty - you fancy doing a holiday swap? You have my four bed semi in Somerset and I'll use your 62 footer in Thailand for a fortnight.