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PostPosted: Sat Apr 26, 2014 11:29 pm 
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Jeffery:
Hang onto that 6 horse 2 stroke, you can't get motors like that anymore.
With my mount I can't put any stress at all onto the rod holders (not the best place to mount). I have spectra string ( 700lb test rudder line) that is tied to the lower unit from those cleats on the sides near the rudder to take up all the rotational stress from the motors, so there is no stress at all on the rod holders.
Actually I think your setup is superior to mine. I have seen others do similar.
I just drilled 1/2 inch holes into the wood then took 1/2 aluminum rod and filed a couple notches into the rod then covere with marine epoxy and shoved the rods into the holes.
If you run spectra string from the lower unit like I did all your problems should go away.
The scupper holes are much stronger than the rod holders and I think your on the right track.
Bob


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PostPosted: Sun Apr 27, 2014 2:44 am 
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fusioneng wrote:
Well I did it, I ordered my second honda 2.3 engine an a pair of ten inch pitch props. Currently with the 7 inch prop running alone without sails just above engine idle (just enough power to engage the centrifugal clutch) propels the boat between 4 and 5 mph. I'm expecting with the higher pitch props that number will be just over 8 mph at just above idle. If the wing sail does it's job instead of sailing at my current 7-10 mph at 1/4 throttle, I expect the boat to sail between 10-12 mph in very light winds running engines at 1/4 throttle. At this point I think I will be hitting the famous brick wall speed wise because of the stock semi displacement hull design.
I have already prototyped out the new back of the boat converting the hull into a semi planing hull (actually shaped just like the hull rear on the weta tri) and it seems to do the trick. As speed increases with a wider behind the rear of the boat no longer squats as you approach displacement speed which will hopefully get the hull up on a semi plane. Once I overcome the brick wall (max displacement speed).
It will likely take me a month or two to get everything dialed in.
My near term phase 1 goal is to average 15 mph plus sailing speeds while still maintaining more than 50-75 mpg using my current setup with the stock Hobie mainsail. I'm still a year away from replacing the Hobies stock sail with a true wing main sail.
Hope all this stuff works.
Bob
Sounds exciting Bob. You adding some kind of planers back there or something more structural?

You have an advantage designing around the constant torque motor. Natural sailing forces and ocean waves oscillate the hull and cause so much drag on different parts of the boat. Even the Akas bury at times

Every time I exceed the speed limit, the hulls flood and I take a bath! So at best, I experience bursts of true speed.


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PostPosted: Sun Apr 27, 2014 12:12 pm 
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Jeffery:
Here is a pic of that spectra string, I just have it mounted to the cleats near the back of the boat, this is what takes all the torque from the motors (the line is 700 lbs test).
Image
The little black line tied to the string and leading upward is the lifting line used to tilt the motor up and down, actually works great.

Here is a pick of all my control lines that feed up to the front cockpit. The dead mans kill switch automatically kills the motor if the motor tilts, or I can kill the motor remotely from the front seat, then re-start with the extended pull rope if needed (that's one thing about the Honda's they always start on the first pull, "really well made"). I removed the tiller and bolted it to the motor mount, so the throttle extension just runs up the right rail of the boat. I can do everything from the front cockpit now, tilt or drop the motor, start and kill the motor, plus complete throttle control.
Image

The second engine will have exactly the same setup only on the other side of the boat. Once I get the second motor installed I will likely run throttle cables and a dual throttle control lever (like on a real boat). Once I'm satisfied with all the controls, I will build a cable management conduit to run all the cables through (a piece of PVC tubing), actually I probably won't bother, I don't really mind how it looks as long as it works.

Here is a link to the two propellers I will be putting on the motors (http://www.deepblueyachtsupply.com/prop ... TCH-012011)

Bob


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PostPosted: Mon Apr 28, 2014 1:32 pm 
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NOHUHU:
If you look at the hull on some of the most modern sail boats they all appear to have a round back end and clean bottom. If you look at this old video at around 2.25 into the video you can see the huge wake behind the boat at around 8-9 mph, and also notice how low the stern is into the water (should have been planing on top of the water by now).
[youtube]https://www.youtube.com/watch?v=bDGNxvCyVeI[/youtube]
Since I have the jib tilted forward it also creates quite a bit of lift and typically raises the tip of the bow out of the water, at cruising speeds 7-10mph it's a couple inches, at higher speeds it gets as high as 6 inches out of the water.

All I did to test out my theory was to duct tape some of that double wall polypropylene board (looks like corrugated cardboard), basically removing the pointed end from the back of the boat and blending in with contour about 3 ft up from the back of the boat, and about 15 inches wide in a fat U shape at the back. The result of this was instead of a pointed wave at the back of the boat that keeps getting closer to the boat as you go faster, then buries the tail of the boat at around 10-12 mph (the squat), the shape seems to hold that wave off the back of the boat by forming a trough. Also the boat rides 3 inches higher in the water at speed ( I'm kicking my self right now, should have taken video).
I'm admittedly no expert in hull design, I just watched my video (at 2.25 into the movie) and saw all that turbulence behind the boat, and thought I would try to do something about it.
My current plan is to pour 8 lb urethane foam over the back of the hull bottom, then contour the back of the boat so it is in a gentle fat U shape in the back about 15 inches wide, with a flat transom. I will then cover with fiberglass cloth and resin. The cap will be removable and held in place by 1 inch straps (buried in the foam). This way if I want to go kayaking I can always just pop it off. Honestly the boat can use a little more flotation back there anyway (especially with twin Honda's @ 27 lbs ea ( LOL)). It's only a half days work and will cost about $75-$100 bucks to do. I doubt it will weigh more that a pound or two. At the same time I was planning to make removable silicone plugs to fill all the holes in the bottom of the boat (including all the scupper holes because I never use the scupper cart anyway with the trailer). The seat drain holes will be just a piece of 3/8 tubing angled backward so it forms a siphon, and flush with the natural hull shape. I will make up removable contoured silicone drive plugs for both mirage drives that will be flush with the hull bottom.
As the boat goes faster as long as you can get the bow and the fronts of the AMA's out of the water (the bowsprit and angled foresails take care of all that), the boat actually planes fairly well, with just the back half of the AMA's in the water they appear to create quite a bit of lift (the AMA's are actually planing at about 9 mph around 4.00 on the video). The hull is semi planing but there is still huge turbulence behind the boat (the speed limit creeping up), and the rear of the boat is still too deep in the water (the complete front half of the boat should be out of the water by now).
Heck I don't pretend to be an expert at any of this stuff, I'm just out there pedaling my pedal boat 10-15 miles a week for exercise, I putz around with the boat once in a while trying to make it more efficient because I get bored pretty fast when I'm going too slow, and want to get somewhere, plus it's just fun for me messing around with stuff.
Bob


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PostPosted: Sat May 03, 2014 3:50 pm 
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Well I have the twin Honda engines mounted and ready for trials tomorrow morning.
Here is a pic of the twin motors mounted
Image

Here is a front view
Image

Here is a pic of the hand made 10 inch pitch special props
Image

Here is a close up of the prop, I still have quite a bit of work to do in the props, as the final version will have winglets like a 737 has.
Image

None of this has been tried out or tested, instead of the usual test and explore first, I just went ahead and built the whole thing, there is a huge risk that it will not work at all, or just be plain stupid. But hey how do you know something until you try it.

Project progress to date:

Phase one completed, wing jib has been in operation a little over a year now and works beyond expectations, Power sailing with the single Honda engine, pedal power, and sails also works beyond expectations, In very low winds (0-6mph) I am able to average 7-10 mph at pretty much any point of sail, yet cost of fuel with the hybrid setup is still very low (around 75 to 100 mpg), basically I can sail around for about 2-3 hrs on 1 tank of gas (fuel tank is 1/3 gallon). Basically I can go out all day for a buck in fuel....

During phase one I noted that with the engine running just above idle (just high enough to engage the centrifugal clutch) with no sails at all the boat goes around 4 mph with a 7 inch pitch prop. At wide open throttle (which I never use) with no sails up the boat goes 9 mph in fairly calm water (with the 7 inch pitch props (8 mph with 6" pitch props wide open).

Phase II (trials begin tomorrow), first I have to break in the new motor so no high speed runs will be attempted. The plan is to run the both motors just above idle (just high enough throttle to engage the clutches) and see how fast the boat goes, I'm hoping for 7-8 mph with no sails at all but have no idea what it will be (because of the drag from the second motor, and also the new propellers are not optimized or tweaked yet, fingers crossed (planning to do high speed underwater video tomorrow of the props in action). Once all dialed in I fully expect to run around 10 mph with no sails at 1/4 throttle. The plan is with all the speeds doubling the fuel consumption should remain about the same (around 100 mpg). With all the sails engaged and power sailing with the wing jib I expect my cruising speed to go from the current 7-10 mph in low winds to 13-15 mph in low winds. Of course much faster if I open up the throttles, but that would defeat the whole purpose of the hybrid setup.

Just in case the ten inch pitch props don't work out ( I have my doubts) I have matched sets of 6 inch pitch and 7 inch pitch propellers all setup as well, I will likely switch them out depending on conditions. (actually the 10 inch pitch props are really intended just for phase III, but who knows they might be great...)

One thing that will affect phase II results is I have not modified the hull yet (converting it to a semi-planing hull), so all the real testing may be delayed, until that is done (about 3-4 weeks to complete, if I ever decide to do it)

Phase III:
Still a pipe dream and probably realistically a year or more out (if I ever decide to do it at all). The plan is to replace Hobie mainsail with a 100sq ft plus rigid wing sail (kind of sort of like an AC 72 wing (but soft and furlable)). Once completed I will re-introduce my existing hydrofoils that I made 3 yrs ago, and see if I can get over 40 mph (at 50-75 miles per gallon (MPG) of fuel) in winds under 10 mph, which is the whole purpose of the whole adventure. Of course the hull mods have to be completed before any of phase III begins.


We are planning to go to our Key West House for a couple weeks in May, I will be doing offshore sea trials down there ( always wanted to say that LOL). Actually we just plan to go offshore scuba diving quite a bit while there, that's what the boat was hardened and setup for in the first place.

Wish me luck ( I doubt any of it will work ( LOL)).
Bob

Actually everyone I have discussed this with doesn't feel any of it is going to work at all. On the boat design forums they are telling me I must have twin 20 hp plus engines in order to get to 30-40 mph

The cool part about the whole system is it still cost less than an evolve (with one extra battery) and give me a range of about 150 miles and I'm hoping to be able sail at average 15 mph, and get over 75 mpg, basically I'm hoping my fuel cost will remain about $50 bucks a year going out every weekend. Well that's the plan anyway.


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PostPosted: Sun May 04, 2014 4:08 pm 
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Well trial #1 was a bit of a disappointment, it turns out the powerboat guys were correct.

Here is a video of my fist time out with twin motors.
[youtube]https://www.youtube.com/watch?v=wmEbHyuOGCE&feature=youtu.be[/youtube]
https://www.youtube.com/watch?v=wmEbHyu ... e=youtu.be

With the engines just above idle the boat was propelled between 6 and 6.5 mph with no sails up. If you recall that number was about 4mph with the single engine. That's the only part of the test today that went well.

It turns out the 8 inch dia x 10 inch pitch props take more turning force than the centrifugal clutches on the motors can deliver, and the clutches begin to slip after a short time sporadically (who knew LOL). Both motors experienced the same problem off and on. You would be going along and all of a sudden one of the motors would increase in RPM, the first time it happened I thought I had sheered the prop pin so I went back to shore to check it, the pin was fine.

I'm probably going to reduce the OD of the props down to seven inches dia, and round off the leading and trailing edges near the tips.

At max throttle neither motor was able to come anywhere close to full RPM, and powersailing the boat didn't speed up much at all as I increased the throttles. With the engines at 1/4 throttle the boat was going between 8 and 9 mph, however instead of speeding up greatly like with the single engine when you open the throttle up, it didn't help much at all to open the throttles up. Actually with just a single engine running at the same throttle setting the wind speed would have been the same.

The whole day did not go as planned, I broke a rudder pin when on shore (bumped the bottom), and had to struggle back to shore to replace it (once I figured out it was steering hard).

The D clip on the bottom of my jib sail fell off while I was out, and the jib went flying on it's own. I had to stop and anchor, retrieve and furl the jib, what a comedy of errors that was. The worst part was the front carrying handle for the boat was attached to the D ring, and this made it a bear to pull the boat up onto the trailer when I was done for the day.

Also I noticed that extra 27 lbs when trying to pull the boat onto the trailer, not a show stopper, but noticeable (glad I did get the 100 lb 10 hp motor now).

As far as cool factor goes, seeing those twin engines a lot of people commented on the boat, and the sound of twin engines running is way cool, reminds me of my old go kart days running twin engines, in an all out modified class. The twin go kart motors had a total unique sound. Actually the engines were 100cc, these Honda engines are 57cc each. They must figure horsepower differently these days though, those old Mac engines were I thought 20 hp ea, and these new Hondas are only 2.3 hp each.

Oh well back to the drawing board. I'm optimistic, I will get this working well.

Bob


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PostPosted: Sun May 04, 2014 4:19 pm 
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I'm optimistic too Bob!

Image

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PostPosted: Sun May 04, 2014 4:59 pm 
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[youtube]https://www.youtube.com/watch?v=wmEbHyuOGCE&feature=youtu.be[/youtube]

Oops. That video is private, Bob. Maybe things are better that way? :lol:


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PostPosted: Sun May 04, 2014 6:44 pm 
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NOHUHU :
I made the video public, might as well share my shame ( LOL). Actually it wasn't that bad today, it does work actually pretty good, just not with the props I had on the boat today, everything else shook down really well (motorwise, of course everything else unrelated broke down, maybe that's a sign). When the big rigid wing jib went on it's own adventure flying around like a kite, that had to be a sign to pack it up and go home.
Bob


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PostPosted: Mon May 05, 2014 11:47 pm 
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fusioneng wrote:
Jeffery:
Hang onto that 6 horse 2 stroke, you can't get motors like that anymore.
With my mount I can't put any stress at all onto the rod holders (not the best place to mount). I have spectra string ( 700lb test rudder line) that is tied to the lower unit from those cleats on the sides near the rudder to take up all the rotational stress from the motors, so there is no stress at all on the rod holders.
Actually I think your setup is superior to mine. I have seen others do similar.
I just drilled 1/2 inch holes into the wood then took 1/2 aluminum rod and filed a couple notches into the rod then covere with marine epoxy and shoved the rods into the holes.
If you run spectra string from the lower unit like I did all your problems should go away.
The scupper holes are much stronger than the rod holders and I think your on the right track.
Bob



Thanks for the tips Bob,

I finally got the old Johnson overhauled and it is running as good as new. I managed to get it up to about 10 or 11mph with motor power only but you were right about the rear wanted to bury down into the water. If you do manage to come up with a way to get this thing to plane I would be thrilled. I was thinking maybe some adjustable "skis" on the end of some pipe and mounted on to the motor mount 2x6 on each side that would add some lift while underway. Hopefully there is a solution as I cannot afford to be stuck 8 or more miles from safety when a storm comes up.


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PostPosted: Tue May 06, 2014 10:50 am 
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Well here we go again, I just finished up the modified 10 inch pitch propellers. I reduced the diameter down to 7 inches (started out at 9", then 8", now 7 ( LOL)). I also added large radius's to reduce the surface area at the tips, and sculpted the top surface to an airfoil shape. Hopefully it won't over drive the clutches in the Honda now, and should work (I've said that before).

Here is a pic of the props
Image

Here is a closeup of the updated design that can be compared to the previous 8" dia design that didn't work.
Image

The intent of the motors is to run the motors at just above idle (, just high enough throttle to engage the clutches, max fuel economy). This should propel the boat with no sails to between 8 and 10 mph (I got about 6.5mph in the first trial but was over loading the centrifugal clutches in the engines (oops)), with the single engine on the same throttle setting and a 7 inch pitch prop the boat propeller to 4-5 mph with no sails up in calm water and no wind.
If this works out, once I open up the wing and main sails it should be more than sufficient apparent wind for the sails to start amplifying the forward motion, and providing lift to the bow (because the jib is tilted forward it creates upward lift). I'm expecting 10-12 mph speeds in no to very low wind conditions.
If everything works out the boat will operate not too differently from a small airplane or gyrocopter (I've built several Bensen gyrocopters). Basically the propeller provides the forward motion, which drives air over the wing, once at a certain speed the wing provides lift, in the example of a plane, the plane takes off, on a sail, the sail provides additional horsepower to propel the boat. Unfortunately with an aeroplane or gyrocopter if the motor fails you fall out of the sky and die, with a sail boat it's not so extreme ( LOL), you just start sailing the old fashion way (that is if there is any wind, or start pedaling with a TI).

With the previous generation that I had been running about a year, it worked better if I had around 4-5mph natural wind. With this design I'm hoping it will work with no natural wind at all (no more sitting irons "ever" LOL). ( Most of the year in this area typical winds are only 4-5 mph most of the year. Here is todays wind forecast (they only have just that one slide for Sarasota, that they just put up every day, most of the year)
Image

The whole setup will likely never amount to anything, but it has been incredibly fun working thru the problems and tinkering in the garage over the last 4 yrs. Of course my goal has always been to have a boat that is human hybrid powered that gets over 100 miles per gallon and propels the boat between 12 and 15 mph with little to no natural wind, with a range of 100-200 miles (a couple gallons of fuel). Obviously If I have more to work with (windwise), the boat will go way faster, but believe it or not that not my goal at all, and I actually don't have much fun in windy conditions with a lot of chop so I tend to stay home on those days (which is only once in a blue moon around here anyway)

That's my story and I'm sticking with it.

Bob


Last edited by fusioneng on Tue May 06, 2014 2:08 pm, edited 1 time in total.

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PostPosted: Tue May 06, 2014 11:04 am 
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fusioneng wrote:
That's my story and I'm sticking with it.

Bob

I like that, Bob. Gritty.

Keith

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PostPosted: Tue May 06, 2014 1:51 pm 
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jeffreydc wrote:
SNIP

I finally got the old Johnson overhauled and it is running as good as new. I managed to get it up to about 10 or 11mph with motor power only but you were right about the rear wanted to bury down into the water. If you do manage to come up with a way to get this thing to plane I would be thrilled. I was thinking maybe some adjustable "skis" on the end of some pipe and mounted on to the motor mount 2x6 on each side that would add some lift while underway. Hopefully there is a solution as I cannot afford to be stuck 8 or more miles from safety when a storm comes up.


That last bit troubles me... If you need to be able to exceed 10 mph to get to safety when a storm comes up, maybe a TI isn't for you, rather than a "proper" powerboat. Even then, relying on any motor to start in decaying conditions has its own risks.

I understand fusioneng's development is to cater for low or non-existent winds, but hanging a huge (in relation to a TI) 6HP motor on your TI is no substitute for prudent awareness of weather forecasts.

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PostPosted: Tue May 06, 2014 6:53 pm 
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tonystott wrote:
jeffreydc wrote:
SNIP

I finally got the old Johnson overhauled and it is running as good as new. I managed to get it up to about 10 or 11mph with motor power only but you were right about the rear wanted to bury down into the water. If you do manage to come up with a way to get this thing to plane I would be thrilled. I was thinking maybe some adjustable "skis" on the end of some pipe and mounted on to the motor mount 2x6 on each side that would add some lift while underway. Hopefully there is a solution as I cannot afford to be stuck 8 or more miles from safety when a storm comes up.


That last bit troubles me... If you need to be able to exceed 10 mph to get to safety when a storm comes up, maybe a TI isn't for you, rather than a "proper" powerboat. Even then, relying on any motor to start in decaying conditions has its own risks.

I understand fusioneng's development is to cater for low or non-existent winds, but hanging a huge (in relation to a TI) 6HP motor on your TI is no substitute for prudent awareness of weather forecasts.



Thanks for your concern Tony but I wasn't really after speeds much faster than 10-15mph. I do watch the weather forecast which in reality doesn't mean very much for the area i live in. On the Gulf coast of Louisiana there could be a 10% or less chance of rain and a thunderstorm could still pop up anytime and anywhere. Any time I see something brewing I head for safety. I have done this for over 35 years and have yet to get caught in a bad one as I always keep an eye on changing conditions. The thought though of having to paddle in for over an hour without alternate power source does not seem fun to me. The motor I have on it is not "huge" by any standard at just 49 pounds. Heck a trolling motor and batter would weigh more than that with less power. My main concern is that, as Bob stated, the back in really squats down and takes on water while under power. Im not to fired up about sitting in a puddle of water for any length of time. When I was out this past weekend the winds were over 20 knots and blowing against me on my return trip. If it were not for that motor I would not have made it back anytime soon.


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PostPosted: Tue May 06, 2014 7:00 pm 
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Tony your being a little harsh on the guy, but it is good advice for all of us.
Jeffery just happened to already have a very rare and hard to find old 2 stroke Johnson, those motors are famous for their reliability and light weight. There actually quite a few guys that have 2.5 and 3.5 hp Mercury and Suzuki 4 strokes on both AI's an TI's. As you know modern motors are a lot heavier than those old two strokes. At least over here you cannot buy a two stroke anymore which is a shame in my eyes.
Bob


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