Stern cabin - too odd on small boats?

Originally Posted by Claus Riepe

OOPS, photos went missing, sorry.

Ok, then. We see a boat thats 23´instead of 20´and it does NOT have a aft cabin. The piece of wood and canvas might give a sufficient shelter for a Porta Potty, but aft cabin is different.

[Claus Riepe]

Here is another drawing of the boat. It's a dutch design called 'Woelwater'. These popup cabin roofs are for instance also used on the Norfolk Broad boats. A clever way to hide a stern cabin from view.

wonderful, and what was your question now?
Or was this the answer?
When we go far enough off the given parameter, we always find the right solution to confirm a biased opinion?

ahh vergiß es..

[Claus Riepe]

For completeness,
here is another example for a stern cabin on a small boat (taken from http://www.woodenboat.com/forum/showthread.php?t=71730 ).

And then there also was the Buckler MkII in the eighties. Sorry no photo, but many will remember.

So again the question, with the known problems of the forward cabin design and building resulting from the compression loads of the main mast etc., why are there so few stern cabins on small boats around today?

[Claus Riepe]

The Buckler MkII,
here is a photo:

[boat fan]

I can go along with form follows function Claus.........

But that Buckler is , well .....plain ugly ..

That mizzen ....not in a good place for an aft cabin layout.
Could work on a Yawl...better on a single masted rig at this size I think..

[gonzo]

Gratis is a nice looking boat

[souljour2000]

"Gratis" is indeed beautiful...thanks for posting her Claus...I guess I don't like how she seems to have only wheel steering though...I have also flirted with the idea of stern cabins in a 20-footer...namely transforming my '83 Hunter 20 into one...I was inspired by the roominess of the Buckler aft cabin/wheelhouse and the head the buckler has in the forecastle area though not so much by it's overall appearance.
If you ask me...starting at 22-23 feet you can have a low headroom sleeping berth aft that could still facilitate a standard aft cockpit above it.
As for the Buckler 23 stern cabin ...it's really a freaking stateroom at that size boat and it's also a galley but could be a wheelhouse too if you keep a very low "forecastle" for visibility...doesn't leave many great options for a lower aft berth or a cockpit above though. The Buckler 23 , though "ugly" is one of the most intriguing designs under 25 feet that I have ever seen for a family cruiser.

[sharpii2]

Originally Posted by PAR

Tall deck structures, well aft will cause the boat to "march" around on it's hook or mooring and also has similar "ends" of the yacht, confines difficulties. Not so much the V shape typical of the bow, but the shallow, truncated shapes common is a stern. With typical freeboard been often considerably less then the forward sections, the space would be more confined (headroom wise) then a forward layout.

Another issue of importance, is what happens to the cockpit location which has to be moved forward. If the aft cabin arrangement has similar accommodations as a forward one, then the well forward, midship cockpit will be quite high (over the cabin below and probably a pretty wet place heading into weather. This is a common complaint in center cockpit craft now, of conventional arrangement

From a practical view point I think you'd be limited to craft of 30 LWL before the idea becomes particularly useful. Beginning with this size, considering a small aft cabin with a conventional layout forward is increasingly more practical. At 35' very doable.

Anything with a mast stepped on it will have to be heavily trussed, be this a deck or coach roof. The compression loads have to be transmitted to the keel and hull shell somehow. A compression post and tie rods can eliminate much of the "heavy" beam arrangements necessary without them. A single bulkhead under the step often doesn't absorb the loads as nicely as we like, as has been born in many production and custom yachts over the years.

In the end, many a workboat has incorporated a wheelhouse aft with a large working deck forward. This is a practical arrangement. The accommodations are typically quite minimal, enough to house the crew, engine and helm, but not much else. Again size is the key ingredient to permitting comfortable accommodations. At 30' you have enough beam to place berths on each side of the centerline mounted engine, with room to pass around the box. Smaller then this, clever engineering and ever increasing compromise must be employed to meet the design goals and provide useable spaces for humans.

I would think a high forward cabin would do that.

Wouldn't a high aft cabin act as the tail of a weathervane, causing the bow to tend to point upwind?

I have recently done two scale sketches with aft cabins. One is in the "...design ideas..." thread in this 'sailboats section.

In it, I describe the aft cabin as a mizzen that can never be struck.

The big problem I had was trying to figure out how to make a simple but cheap steering system that could go along with the aft cabin.

Auxiliary power was also a problem.

I added a long keel wit generous areato cut down drift.

I just don't see how a boat with much of its windage aft would wanmt to charge around its anchorage.

[souljour2000]

I dunno about sailing at anchor with aft cabin boats either...I bet it wouldn't be too hard to make a scale boat out of papier mache and try some different things with a kiddie pool and a decent fan...just watch out for that electrical cord...!

p.s.- you can start with a base shape and then add stern cabin shape with any good craft glue..most are water-based but fairly waterproof for a few minutes...then let the thing dry out and add a new shape ...rinse repeat...maybe I will try it...screw all the high tech Bethesda naval model basins.!..Anyone see 60 minutes a couple years ago about what happened to six new US coast guard cutters?..they tried to add an aft section to each of them ...after Lockheed or someone screwed up the stern additions...the USCG declined them and they couldn't even give them to the Brazilian Navy because they determined they wouldn't make it to Brazil...

[timothy22]

Been around for years, tons of versions built. I've seen some photos of the aft cabin that look very impressive for a 30 foot boat.

[boat fan]

Nice one Tim....does not look too bad either.

Just shows what only few more ft in length can achieve.

[Claus Riepe]

Originally Posted by sharpii2

...
Wouldn't a high aft cabin act as the tail of a weathervane, causing the bow to tend to point upwind?

... I describe the aft cabin as a mizzen that can never be struck.

... The big problem I had was trying to figure out how to make a simple but cheap steering system that could go along with the aft cabin.

Auxiliary power was also a problem.

Sharpii,
thanks for that aspect, the welcome stabilizing effect from a stern cabin windage.
In one raid last year we were rowing into some headwind. We overtook and subsequently watched one boat with a small forward cabin which could no longer be rowed straight ahead due to the forward cabin windage destabilizing it's course. The rowers were not able to hold her.
In this context I am attaching two photos of stern cabin rowing boats, the RNLI 'Ryder' lifeboat and Andre Mateus' Atlantic crossing boat.
Quite clear that the cabins are not merely there to self-right the boat from inversion, but also to stabilize their upwind capabilty.

Re the steering problem,
a wire rudder yoke would work well. We tried stainless steel wire, which broke quickly. Ever since it's Dyneema, and that shows no sign of tiring over the blocks.
Re the auxiliary,
electric could be a solution to keep the stern cabin free from gasoline/exhaust fumes. Only last week we saw a boat with an electric pod integrated into the rudderblade.

[sharpii2]

Originally Posted by Claus Riepe

Sharpii,
thanks for that aspect, the welcome stabilizing effect from a stern cabin windage.
In one raid last year we were rowing into some headwind. We overtook and subsequently watched one boat with a small forward cabin which could no longer be rowed straight ahead due to the forward cabin windage destabilizing it's course. The rowers were not able to hold her.
In this context I am attaching two photos of stern cabin rowing boats, the RNLI 'Ryder' lifeboat and Andre Mateus' Atlantic crossing boat.
Quite clear that the cabins are not merely there to self-right the boat from inversion, but also to stabilize their upwind capabilty.

Re the steering problem,
a wire rudder yoke would work well. We tried stainless steel wire, which broke quickly. Ever since it's Dyneema, and that shows no sign of tiring over the blocks.
Re the auxiliary,
electric could be a solution to keep the stern cabin free from gasoline/exhaust fumes. Only last week we saw a boat with an electric pod integrated into the rudderblade.

Thanks, Claus.

Just for fun, I'll upload a sketch I did for that other post.

It is a 20ft x 8ft scow with an aft cabin which is supposed to have standing headroom for a 6ft 4in man.

The full keel on it was drawn to enable it to sail on a super shallow lake, which has an average depth of only one meter.

Not all of its design problems have been solved as it is just a concept drawing to show about the smallest, lightest sailboat that I think can support such a cabin and still be manageable.

[Claus Riepe]

Sharpii,
thanks for that.
I know there will be guys out there ridiculing rough sketches, but then I think it must be understood that this is about discussing the concept of stern cabins on small boats. This is not about perfection.

I have got two sketches here from my friend Tony L. (Thanks T.!).
These are about putting a stern cabin hardtop on an even smaller boat that you did. ( And having a junk rig into the bargain.)

We had a discussion about 'Form Follows Function' and one guy said that that is no good with boats. I disagree, boats -at least until the advent of the engine- were the perfect proof of FFF. The stern cabin has been dominant for centuries if not millenniae. It must have served it's purpose better than the forward cabin, otherwise it would have been weeded out long ago.