TT35 at the Annapolis Boat Show

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OK Ben it soulds like they are close to a 180 crank. The only succesful 180 crank engines I know of are the old Brit bikes. They all had massive crankshafts (to ballance the counterweights to the pistons) so I’m going to guess this new engine will pay a weight penalty w a heavy crank. Looks like the pistons and rods are heavier too. And there’s two wrist pins on the piston and that adds to the weight but if it were a single wrist pin it may be about the same total weight ? So the chance of this engine being comparatively light is low or less.

But the high torque they get from only two cylinders is golden. I see it’s 50/50 bore/stroke. Makes for a compact engine too. I see the chain driven cam drive in-between the cylinders adds to the compactness. Many motorcycles are driven thusly.

Makes me wonder if a boxer engine w the two crank arrangement would have even more advantages. Food for thought.
:thumb:
 
Did the owner of Spirit Song (hull #2) take delivery?

Sorry, can't seem to find their blog anymore and no mention of it on the GH web site.
 
If people are concerned about the vibration of a 2 cylinder diesel, I'd bet they really get excited with a 1 cylinder diesel or one cylinder gasoline engine.
 
When timing a 2 cylinder steam engine, one adjust the slide valve of the 2nd cylinder opens as the other valve closes. Unless perfect, sometimes one must give a bit of help with the flywheel.
Same way with the old farm tractor engines, spin the fly wheel to start the engine. Sometimes it had a duel fuel system, start the engine on gasoline and when running, switch to diesel.
Gosh, am I showing my age again?
 
If people are concerned about the vibration of a 2 cylinder diesel, I'd bet they really get excited with a 1 cylinder diesel or one cylinder gasoline engine.


:iagree:

Those engines don't vibrate. They dance all over the bed, the engine bed. :rofl:
 
Did the owner of Spirit Song (hull #2) take delivery?

Sorry, can't seem to find their blog anymore and no mention of it on the GH web site.

Last blog post in March. No updates on the TT35 that I can find on their site. Facebook doesn't indicate any deliveries taking place.
 
Spirit Song blog activity picking up

For those who have not noticed, the owner of Spirit Song is starting to post some info about his new TT-35 on his blog. Latest comments based on a couple of weeks usage. 5 mpg at 10 mph based on the first 8 hours of use looks good. I think this link to his new blog was listed earlier in this tread, but here it is again:

https://oldmanriverandcoco.blogspot.com/2017/12/
 
Kudos to these brave peeps for having their new design/boat scrutinized by all of us. I'm glad this project seems to be working out ! It must be daunting having the boating world watching and waiting for every new item of Mirage to satisfy and impress.
 
Looks like they have the solar panel option on Spirit Song. They may have to tow their dinghy when they do the loop as they do have a dog for a crew member. Looking forward to seeing how they overcome that challenge.
 
Washer/dryer, water maker?
A real head, not a porta-potty?
The only down side, but livable, a wet head.
You are home free!!
Better than camping.
 
Looks like they have the solar panel option on Spirit Song. They may have to tow their dinghy when they do the loop as they do have a dog for a crew member. Looking forward to seeing how they overcome that challenge.

Training the dog to use either artificial grass pad, or perhaps a 3'x3' real grass box, pads or enjoy the break in traveling by visiting shore more often with a plastic bag.
 
Training the dog to use either artificial grass pad, or perhaps a 3'x3' real grass box, pads or enjoy the break in traveling by visiting shore more often with a plastic bag.

I guess dogs are smarter than I am!

And if they use mooring balls, they can use the water taxi ...if available.

Maybe they don't need a dink after all. So why do I see so many Great Looper boats with dinks?
 
Maybe they don't need a dink after all. So why do I see so many Great Looper boats with dinks?

Same reason there are exit ramps on the interstate. If you only go from marina to marina, you will probably miss 50% of the sites to see on the Great Loop. A shallow draft dinghy will take you so many more places.

Ted
 
I recently discovered this thread (I've been busy and don't log on as often as I should) and I read all nine pages with great interest since I have always been interested in trailerable or transportable boats. Some people think that trailerable implies "legally" trailerable, i.e. less than or equal to: 8.5' beam, 13.5' height etc. To appease them I started calling boats that require an oversized load permit transportable. It is true that most boats could be transported, but some are much easier than others. Some boats have to have their flybridge or upper deck removed and may require one or tow pilot cars (which essentially doubles or triples the transport cost because you're paying for professional drivers by the hour). Therefore, I define economically transportable boats as boats that can be transported without costly modifications or pilot cars.

The main advantage of an economically transportable boat is you could make it large enough to be a comfortable live aboard (my wife doesn't consider any legally trailerable large enough to live aboard) and large enough to have some offshore capability.

My dream would be to get an economically transportable boat that my wife would be willing to live aboard. However, since economically transportable boats don't currently fit the reality of my budget, I purchased a Nimble Wanderer which is an affordable legally trailerable trawler like boat. Our experience with our Nimble Wanderer so far is that she is a hand full to trailer. At almost 10,000 lbs with a 3,150 lb trailer she needs a 3500 class pickup (I purchased a Sierra 3500 HD which does the job quite well). Also, the trailer/boat combination is ~37' long and 13' 6" high so you need to be careful where you stop for food and fuel.

As for those who are uncomfortable towing an oversized load, I'd say just hire professional boat movers to move it for you. Most people would only move their transportable boat twice a year, and the cost of transporting on land will be lower than in the water.

Regarding the Great Harbour TT35, I applaud their effort! They developed a more affordable boat with more accommodations than would fit in a legally trailerable boat. However, I don't agree with some of their design decisions. The biggest issue I have is with the choice of outboard motors. Outboards concentrate a lot of weight at the stern which requires a comparable mass near the bow. Since the moment of inertia is the summation of mass times distance to the center of gravity squared this contributes to a high pitch moment of inertia, which means it will be slow to respond to waves and more water comes over the bow. Also, I believe cruising boats need substantial electrical power, but outboard motors have very small alternators, which are only intended to recharge the start battery. The Suzuki DF60A has a 12 Volt 19 Amp alternator, which means the optional generator would be mandatory for me. Second, as a Mechanical Engineer, I think the air cooled generator is an intrinsically bad idea. Getting airflow to below deck engines is difficult on a boat and air has 100 time less heat transfer capacity than water. A water cooled generator would be a superior solution IMHO. I think the TT35 would be adequate for most sheltered water boating like the East Coast ICW, but I think the light displacement and shallow draft combined with a high pitch moment of inertia would restrict her to offshore use to fair weather. Finally, the "tailgate" swim platform looks like a good idea at first. However, using it in rough water is going to be very interesting. I'd prefer a fixed platform and a smaller transom gate with a raised threshold.

The SeaPiper 35 is interesting and could be transported with a little larger truck. However, I'm not a fan of the mid cockpit and going forward to use the head in foul weather could be an issue.

I would like to nominate Tad Roberts Enavigo 39 Enavigo 39 Classic Motor Yacht ~ Power Boat Designs by Tad Roberts or Enavigo Power 39H - Enavigo.hr (although I like Tads exterior much better!) as a potential liveaboard transportable design. With a length overall of 39 feet and a beam of 10.9 feet it would be transportable with an oversized load permit and wouldn't require a pilot car on multi lane highways. The displacement of 18,300 lbs means it would require a capable truck (although my Sierra 3500 HD could tow it with a gooseneck trailer). The heavier displacement and 1 meter (3.28 feet) draft should make her much more capable offshore than the TT35 and slightly better than SeaPiper. I like the arrangements of Enavigo much better than the TT35 or the SeaPiper. Now, if I could just afford it!
 
I'd rather have an MDT to pull that weight and size. Not a ton truck.
 
My Sierra 3500 HD has a 3.5 Ton payload capacity (a little more than a ton) and is equipped with a 445-hp 6.6-liter Duramax turbodiesel with 910 lb-ft of torque and the Allison 6 speed automatic transmission. It is rated to tow 23,300 lbs. That is more than some medium duty trucks. Also, the 3500 HD includes all the towing features generally found on a MDT such as trailer brake controller, exhaust brake and trailering camera package. Not to mention lane departure warning, front collision warning, ... but to each his own. YMMV.
 
To Portager:

As far as I can tell the Enavigo 39 and TT35 seem to be very similar boats. The profiles are very similar. The information you provide does not show the interior arrangement of the Enavigo. The only significant differences that is apparent from the information you supplied is that the Enavigo is a inboard diesel vs. outboards and the construction is wood vs. FRP.

In the case of the TT35 you have the advantage of the engines external to the hull which frees up a lot of space. Dual engines vs. a single, which has advantages in redundancy and handling. Maintenance of gas outboards is significantly simpler that an inboard diesel engine and its supporting systems.

In the case of Enavigo, you have diesel fuel which some people are more comfortable with. However, while diesel engines may have higher rated alternators (but not always), they are still air cooled.

However, to each their own. The idea and execution behind the TT35 has a lot of appeal to me. As far as I can tell the Enavigo does not present any advantages over the TT35 that makes it a noticably better choice than the TT35 (IMO).
 
The Enavigo Power 39H - Enavigo.hr link has the arrangement if you open the gallery or brochure.

The first difference between the Enavigo and the TT35 is the single diesel inboard vs twin outboards. The diesel is water cooled not aircooled and maintenance on a single diesel will be much less than two outboards. The inboard diesel is under the floor, so it doesn't take interior space. Also, diesel won't create combustible fumes that collect in the hull and explode. Yes, the diesel can be equipped with a high output alternator. My 75 HP Yanmar drives a 200 amp alternator using a serpentine belt. Works great. I get 150 amps (1.8 KW) at high speed idle and 200 amps (2.8 KW) at cruise speed.

The second difference is the Enavigo 39 displacement is 2.8 times higher and draft is 2.6 times higher. The TT35 is practically a flat bottom. Sea keeping is going to be vastly better with the Enavigo. For doing the loop you might think you don't need much seakeeping, but crossing lake Michigan is going to be very interesting not to mention the open ocean stretches.

The interior arrangement look somewhat similar, but the Enavigo has a second stateroom with two bunks. The second stateroom comes in handy if you have guests, but it is also useful for storage.
 
Keep in mind the concept of the TT35 was to eliminate below the waterline thru hulls. With a 16” draft, space for thru hulls can be an issue but I believe hull number 2 has a traditional marine genny. In agreement with you on the alternator issue. As you mention, it will be interesting to see how they resolve the air cooled genny issue.

On the loop, you don’t cross Lake Michigan in most cases but hug the western shore of Michigan and almost all loopers wait for good weather windows. Getting across the Gulf of Mexico will be more of a problem if a traditional crossing is attempted but with its shallow draft, the TT35 should be able to hug the west coast of Florida and visit ports other loopers bypass.

Looking forward to reading the blog of Spirit Song on how it works out on the loop.
 
Not sure everyone will agree with you on what you see as advantages with the Enavigo over the TT35. I have a boat with similar characteristics as the TT35 (outboard power, lightish weight, flatter hull, shallow draft) and I am quite happy with it. Even had it on Lake Michigan.

So far all the illustrations you have provided on the Enavigo seem to be renderings. Do any of these boats actually exist?
 
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The Enavigo Power 39H - Enavigo.hr link has the arrangement if you open the gallery or brochure.



The first difference between the Enavigo and the TT35 is the single diesel inboard vs twin outboards. The diesel is water cooled not aircooled and maintenance on a single diesel will be much less than two outboards. The inboard diesel is under the floor, so it doesn't take interior space. Also, diesel won't create combustible fumes that collect in the hull and explode. Yes, the diesel can be equipped with a high output alternator. My 75 HP Yanmar drives a 200 amp alternator using a serpentine belt. Works great. I get 150 amps (1.8 KW) at high speed idle and 200 amps (2.8 KW) at cruise speed.



The second difference is the Enavigo 39 displacement is 2.8 times higher and draft is 2.6 times higher. The TT35 is practically a flat bottom. Sea keeping is going to be vastly better with the Enavigo. For doing the loop you might think you don't need much seakeeping, but crossing lake Michigan is going to be very interesting not to mention the open ocean stretches.



The interior arrangement look somewhat similar, but the Enavigo has a second stateroom with two bunks. The second stateroom comes in handy if you have guests, but it is also useful for storage.



What is the price point of the Enavigo?
 
P.S. Ranger Tug has come out with a couple of new versions of their boats that are outboard powered, the 23, 27, and 29. In the past these have been a diesel inboard boats. I hear the the 27 is quite popular. Maybe there is something to this outboard thing after all.

The 29 I saw at the MIBS had twin outboards and a separate conventional marine generator.
 
I'd love to see a way to easily switch a big outboard between propulsion and "PTO mode" for driving a high output alt, watermaker and/or eutectic fridge setup.

Two engines gives a lot of flexibility plus redundancy.
 
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