Pocket cruisers

Are you sure it is the 9.5m sport cabin and not the 12 m sport cabin ?

Seems that forepeak (1 m) + v berth (2m) + head (0.8m) + settle (2m) you are not at the half of the boat with 5.8 m.

 

Guillermo,

Steveoh, the guy who runs the Fishyfish Tolman site, posted at around 5-30 California time 18th November about Renn's new design. " know it's not new news, but Renn sent me pictures of his new
design. You can see them:

http://www.fishyfish.com/renn_tolman/index.html

It's gonna be interesting to see how it turns out, and what sort of
mileage it gets. It's my understanding that he's aiming to design/
build a super efficient keel drive, diesel powered boat. Folks can
correct me if I'm not totally clear on this."

Steveoh has also placed Renn on Wikipedia. http://en.wikipedia.org/wiki/Tolman_Alaskan_Skiff

Tom,

Many thanks for explaining the width of the chine flats on "Liz". You have achieved in your design a craft than runs true and smooth in a manner that can only be accomplished on other designs by retro fitting hydraulically or electrically powered flaps.

It has set me thinking that my 33 footer with 12 degree deadrise monohedron from transom and 24 degrees deadrise at the bow, would benefit by increasing the chine flats from 9" at the transom to 15", keeping the 5 degree negative angle. This would appear to increase stability at rest and achieve planing without the "transitional hump". You gave "Liz" a 25 degree bow deadrise, a difference of 15 degrees. On that basis, I suspect I should look at setting my convex shaped bow at 27 degree deadrise to minimise the wake at 4 mph in harbours and rivers.

All the best.

Pericles

 

Tom - correct as usual... that's what comes from posting off the top of your head, without giving time to think 1st!
For those without access to the derivation of Lord's aspect ratio:

Aspect Ratio = mean beam / wetted length

where mean beam = width of dotted rectangle shown below
wetted length = distance from transom to a point midway between the entrance of the stem and chine.

 

Another interesting boat, Gerr's 28' Offshore Skiff:
http://www.gerrmarine.com/power_30.html

LOA: 28 ft. - 3 in. (8.6 m)
LWL: 24 ft. - 0 in. (7.3 m)
Beam: 8 ft. - 0 in. (2.4 m)
Draft Hull: 11 in. (28 cm)
Draft Propeller: 26 in.
Displacement: 5,200 lb. (66 cm)
Headroom: 6 ft. - 4 in. (1.93 m)
Gasoline: 120 gal. (454 l)
Water: 25 gal. (95 l)
Power: 75- to 150-hp outboard
Speed with 75 hp: 16 knots cruise, 19 knots max
Speed with 150 hp: 23 knots cruise, 26 knots max

 

Guillermo,

Last year I had an oportunity to drive and observe an Offshore 28 owned by a friend. First, it is a dory form with the usual characteristicsof that type. It is a flat bottom hull with a narrow waterline beam on the bottom of only 5' on a max sheer beam of 8'. Because of this narrow bottom, it is pretty tender, especially at the dock. Stepping aboard is something of a surprise. It banks steeper in a turn than any other boat I have ever been aboard. Although 28' over all, it is not a very big boat in terms of interior room and most movement will naturally be restricted to inside the bottom beam as in most boats.

When running together with only the owner of the Offshore skiff aboard and 5 adults aboard the BJ24, we were about 3-4mph faster with our 50hp than he was with a 75hp. Gerr designed the boat for fishing offshore and it is undoubtedly better suited to that than cruising inshore and protected waters.

These are my impressions but your mileage might vary.

It has been suggest here and elsewhere that prospective boats shuld be subjected to a comprehensive list of attributes to see how they compare in a more objective manner than just a quick look affords. For instance, some people just like dories and tend to overlook their considerable limitations when used in ways completely counter to that which the dory form was developed for and was so successful at.

 

Guillermo,

That Dave Gerr Skiff is very good looking and with the flat bottom even simpler to build than a Tolman. Alaskan seas might be a little unforgiving however, so a V hull would probably be my choice, were I living there.

As far as Renn's new design is concerned, Skiffkits posted the following.

"I've known about it for quite a while. Renn jokingly accused me of
being an "Industrial Spy" while I was taking pictures of the model
at the Homer show. But since he's let the cat out of the bag!

His new design is based on a Rescue Minor type bottom married to the
Jumbo sides/sheer. The RM design is an Atkins design from the '20-
40's, google Atkins boat designs. Most RM type hulls are small
diesel inboards (18-25 hp), some were larger, with a max hull speed
of 18-20 knots. The prop sets directly behind the "Dead Box", the
design is said to be super effiecent, it is also very shallow draft
and can be easily beached as it will sit level, the prop sets in the
tunnel and is protected by a metal bar running from the dead box
under it to the rudder protecting the prop. Renn was hoping to
start on the full size hull (22') about now, don't know if he has.
Tim Davis, now back in Homer, plans on building a similar hull, 28'
when he gets his shop completed.

I highly doubt kits will be produced as it is a much more
complicated bottom design, Renn plans on using a somewhat different
building techniques and materials that probably will not lend itself
to kit building.

There's a company in the UK that marinizes small Japanese Kubota
diesels and imports them to the US, they would be the power of
choice. At one time there was also someone marinizing VW diesels
from Rabbits in the US.

Renn's shooting for less than a gallon a cruising day for fuel
consumption.

Will be interesting to see how it progresses.

Neal
Skiffkits"

Should anyone wish to join a lively, friendly and informative group of boat builders, just apply at http://www.fishyfish.com/tolmanskiff.html

Regards,

Pericles

 

You right, we still wait drawings for the similar version of the 9,50 from Van Dee Stadt design. This is the 12 mt sport cabin and I attached it to show the cabin design style, but the 9,50 will be very similar even less roomy.

 

Pericles (I'd love to know your name, just not to call you by the nick),
What about the room for the propeller? It seems there's not enough for an effective one, unless the blades come down further than the hull bottom, thus avoiding beaching.
Cheers.

P.S. Please excuse me if Pericles is your name!

 

I thought so, thanks for the info on the real thing.
Cheers

 

Food for thought.

I have just spent the summer and fall in possesion of a boat which meets many of the criteria mentioned in this post. It is an MC29 Motorcat which is trailable, light, fairly quick and gets outstanding fuel economy with its single diesel. I'm putting it up for sale with just 66 hours on the engine.

Why? I'm going back to sailing. Fortunately my sailboat, though listed, did not sell.

In the MC29 the best cruising speed from a comfort and economy point of view is 18 knots. At that speed we covered long distances quite quickly. When cruising my preferred days run is 20 to 30 miles between anchorages, even less in some areas.

We are early risers, and the result is, we tend to be at our destination by 9 AM! What to do with the rest of the day? Of course we could make longer trips each day, and easily cover 100 miles or more. But I'd rather go slower and enjoy the scenery. We did go from Vancouver to Seattle in a day for the boat show, but that was a delivery trip, and quite tiring.

Another thing is that any time of year, is there is a sunny day, with a bit of wind, I love to take the sailboat out alone, and just sail back and forth in English Bay, enjoying the day. This seems completely pointless in the powerboat, just uselessly burning up fuel. On the sailboat I can engage the autopilot and eat lunch, whereas on the MC29 I heave to for that as you must keep an eagle eye out for debris in our waters.

Guillermo mentioned in one post that his kids get restless on trips longer that an hour or so. Mine are grown up now, so no longer an issue. But perhaps the Banjer 37 is more of a slow motor boat than a sailboat. My Hanse 371 Tangleberry is a high performance sailer, quite thrilling in a decent breeze, and when the kids were younger they enjoyed steering it. My son loved setting the spinnaker and made a great foredeck man.

So, here are my plans for the sailboat. Already it has a hardtop dodger and windshield, but I will add a full cockpit enclosure. I will add an electric winch handle (the Cranker adapter pluse a cordless right angle drill). This is because I do find raising the big mainsail a bit of a chore. Once it is up, the boat is very easy to handle with its self tacking jib. A new, high tech jib will improve performance further.

Part of the fun in sailing is planning to take advantage of the wind and tide, and timing it. In the MC29 we just go, as we have enough power top overcome the local tides.

I used to thing that power boat people were restless energetic people who just had to move fast, but having tried it, I realize that I'm the restless, energetic type and a sailboat suits me better!

By the way, my sailboat has excellent accommodation for 2 couples, and greater weight capacity, so it is better suited to my 2 month summer vacation (I'm semi-retired, 58 years old) than any power boat I could afford. If I get another power boat in future, I'm thinking Nordhavn or Diesel Duck type. Then I suppose the fun will be sitting in the engine room tinkering...

Grahame Shannon

 

Sensible thoughts Grahame. I agree with you 100%
By the way, very nice boat the Amazon 44. I'm going to list it at my Motorsailers & Motorsailing web pages.
Some questions about her:
30600 lb displacement in what condition?
May I know her body draught, sailing area (I,J,P,E) and heeling arm, please?
(And also wetted surface for the 30600 lb displacement?)
Cheers

 

The problem on the 9.50 would be headroom (among other space problems). Seems that the 9.50 classic have nowhere standing headroom in the cabin. Perhaps the sport cabin can do better in the pilothouse.

 

will ask to Chees about (Van De Stadt owner/designer)

 

Guillermo,

In post 237 you mentioned removable sterns. There is such an item that also enables the repowering of craft with time served inboards.

http://armstrongnautical.com/brackets.htm

At the end of October I commented on their possibilities at the Tolman forum.

---"Ken's link to the Armstrong deckplates also has another heading. "Brackets". How about a positive flotation O/B bracket? It could be created in marine ply and bonded to the transom. It is certainly worth a look.

If you think of the "Bracket" only as a full width extension of the hull, say lengthening the 22 footer Jumbo to 25 feet at a lower sheerline, then the extra length is used as a step up over the transom. Built to match the underwater lines as a completely separate component with its own flotation chamber and bonded to the transom, if it did not function well, then a chain saw would part it from the vessel with ease. The inherent flotation would enhance fitting twin O/B engines.

The Armstrong "Bracket" is a fit all design, hence it does not extend down to the bottom of the hull. There are too many variations in transom deadrise. Tolman builders can match the hull shape and thus extend the effective length of any of the skiffs as well as being a mounting platform to climb aboard. As a separate component, it could be assembled inexpensively and bonded to the transom with epoxy. If it were sucessful, then it could be either fitted with Armstrong deckplates or buoyancy foam filled. The unit represents a method of testing the effects of increasing waterline length without great expenditure."--

I would also add that instead of filling the unit with buoyancy foam the interior could be fitted with petrol tanks thus keeping the fire risk out of the boat's interior.

This could lead to the concept of "cut & shut" boats. Slip in an extra compartment if you have guests.

The Chinese "treasure" ships of the Ming dynasty were built with separate water tight compartments

Size of the Chinese Fleet
“In its heyday, about + 1420, the Ming navy probably outclassed that of any other Asian nation at any time in history, and would have been more than a match for that of any contemporary European State or even a combination of them. Under the Yung-Lo Emperor [Zhu Di] it consisted of some 3,800 ships in all, 1,350 patrol vessels and 1,350 combat ships attached to guard stations (wei and so) or island bases (chai), A main fleet of 400 large warships stationed at Hsin-chiang-khou near Nanking and 400 grain-transport freighters. In addition there were more than 250 long-distance ‘Treasure ships’ or galleons (Pao chuan), the average complement of which from 450 men in +1403 to over 690 in 1431 and certainly overstepped 1,000 in the largest vessels. A further 3,000 merchantmen were always ready as auxiliaries, and a host of small craft did duty as despatch-boats and police launches. But the peak of the development which had started in 1130 came in 1433, and after the great reversal of policy the navy declined much more rapidly than it had grown, so that by the middle of the +16th century almost nothing was left of its former grandeur.” – Needham, Vol 3, p. 484 (Martin Tai evidence).

The Chinese Fleet arriving at Calicut
“More than eight hundred sail of large and small ships had come to India from the ports of Malacca and China and the Lequeos [Ryuku Islands], with people of many nations, and all laden with merchandise of great value which they brought for sale… they were so numerous that they filled the country and settled as dwellers in all of the towns of the sea coast.” (Chaudhuri, p. 154) (Evidence provided by Professor James Finlay of Arkansas University.)

Bases
In parallel with Zheng He’s development of his fleet went that of overseas bases. By 1421 the Chinese had bases around the Indian Ocean and down the East African coast to Sofala. They already had an extensive network across Indonesia, the South China Sea and in New Zealand.

Experience
Since 1405 there had been five voyages becoming progressively more adventurous as the years went by. During the fourth voyage the Chinese had separated their fleets and sailed far down the East African coast.

Where the Chinese fleet went
“Chinese . . . with Tartairs, Japanese and Koreans . . . crossed the Maritime Stretch . . . into the Kingdoms of Quivira populating Mexico, Peru and other eastern countries of the Indies [America]” – Carlos Prince (Annex XXVI).

SUMMARY
The whole world had been charted before Europeans set sail. Only the Chinese could have done so.

http://www.1421.tv/pages/evidence/content.asp?EvidenceID=168

Regards,


Pericles

 

That's a nice solution for some boats. But in the EU (from the laws point of view) one have to be careful when the 'bracket' adds hydrostatic or hydrodinamic lift, it's then considered as part of the regulamented LH (length of hull) so maybe affecting the fiscal categorizacion of the boat (So more taxes to be paid)

The Arabs (probably Nabateans) were sailing the Indian Ocean at the same time, also charting the zone and even coming up the South China Sea. Chinese and Arabs traded those seas hundreds of years before the europeans even thought in going there (precisely to try to take from the arabs the exclusivity of the trading of spices and the like)

Cheers