Jet propelled customized 14 ft Aluminum Semi-V Duck Boat - Design/Modify sec.

The previous build post left the boat stuffed with flotation, ready for decking. As most projects go it's taking three times as long as I expected but progress is being made.

First step is cutting the panels out that will make up the deck. The sides are the two 10' X 10" strips sheared off by the aluminum supplier. The bow was cut from the left over piece from the last decking project. In between was cut from the remaining 28" X 10' sheet.

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Note the new grab handles on the stern. With the deck there is nothing to grab so handles are needed.

View attachment deck start stern.JPG

I could have sworn I took a number of riveted deck pictures, but as I search through the photos and down size them, there are no shots at all, other than when taken to show the jet conversion. This shot is the best of the deck, but it is taken to show both the motor board and the aft deck fitting. The top of the board down to the bottom is 22".


View attachment fitting stern deck.JPG

The aft deck was left off until the motor was converted, then I needed access to mount the bilge pump and the battery box frame. Once the deck is mounted I don't want to have to take it off again. This shot also shows the motor board sandwich, 2 sheets of 3/4 ply epoxied together wrapped in .06 aluminum fit between two 2X2 X .125"aluminum angles. For the motor to clear the boat's aft rail I had to add another 3/4 ply board to the outside top portion. Once the overall height is finalized I plan on capping with another sheet of aluminum and 5200 to keep water out of the sandwich.



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The shallow water money shot: The leading edge of the intake foot is roughly 1/4" below the boat's bottom.



View attachment Jet from the stern.JPG

In the photo above - new bunks. I took an afternoon off to replace the bunks. I was planning on it anyway but when I dropped the boat off on the lawn I found the back end of one of the bunks rotted off under the carpet. I redid the bunk mounts and hardware and installed 6' 7" long pressure treated 2" X 6" boards with slick sticks on them to ensure wood never touches the aluminum. I did this on my Starcraft's trailer and it's coming up on fifteen years and they are in great shape. A new winch was bolted in place in place of the tiny old rusty one. I am not fond of the axle, but that may be next years project. This one should do find for the season.

With the aft deck still off, this afternoon was mount the bilge pump and create the battery box mount. The bilge pump will discharge straight up through the deck as the hose enter a 90 degree barb. I have plans to armor the discharge barb up if needed. I'm hoping it will sit tight in the deck penetration. For gas hose and motor wire I purchased a vinyl boot to protect their deck penetration.


View attachment batterybox.JPG

And Dave (aka: Colonel Popcorn), I doubt you can tell from the pictures, but I did switch out to riv-nuts for both the battery switch mounting plate and the electrical panel; I had to get into the panel and the rivets drilled out nicely but I realized that while I have a screw driver in my boat toolbox, I don't have a drill and pop rivet gun in the field. Thanks for making me think!

Tomorrow is supposed to rain so maybe I will actually get the aft deck on.

Scott

View attachment fitting stern deck.JPG
 
Scott Farris said:
And Dave (aka: Colonel Popcorn), I doubt you can tell from the pictures, but I did switch out to riv-nuts for both the battery switch mounting plate and the electrical panel; I had to get into the panel and the rivets drilled out nicely but I realized that while I have a screw driver in my boat toolbox, I don't have a drill and pop rivet gun in the field. Thanks for making me think!
Scott
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Glad I could be of service. [;)]
 
Scott Farris said:
Thanks Ed,

Just have to watch out and not freeze one's butt to the deck, like the proverbial tongue on the flag pole. But that's one of Mr. Sutton's wonderful stories from yesteryear.

Good luck!
Scott
Click to expand...

Just catching up on this thread. Nice work. Love the concept--would be perfect for some of our rivers up here. Jet drives got very popular for a while among folks who fished our rocky rivers, but the craze seems to have died a bit. I see fewer and fewer of them. The most extreme version was a striper guide on the Damariscotta River who had a big custom welded aluminum boat, maybe 25 feet, with a very large inboard jet drive. There was a section of the river with a set of three "reversing falls" that I used to fish by canoe and kayak, and it could get interesting if you were out there in the dark and he came through at 3/4 throttle! Fortunately, we could hear him coming from a LONG way away.


As for freezing your butt to aluminum, I can say from experience that it is very possible.
 
View attachment Bare ready for Sea Trials.JPG

Rainy day Thursday was spent wrapping up the aft deck. creating the penetrations for the bilge pump outlet and one for the engine's gas and electric lines. I ran the motor's lines through a chunk of bike tire inner tube to protect them at the aluminum interface. The Vinyl boot is installed to minimize water entry. The deck was then riveted in place and the rear coaming cut and fitted. The deck's full perimeter was gone over with both a grinder, sanding disk, as well as a file to align with the rail and round and smooth the edge.

This morning I added the oarlock sockets, they are fit to chunks of the channel and riveted to the rail. These may be upgraded to folding oarlocks in the future, but I wanted something in place fast for me to be able to row home if there is a motor issue.

View attachment completed aft deck.JPG

Then it was off to the Rainbow! As in the Rainbow Reservoir, a small impoundment, 3 miles from home, on the Farmington River. It's an ideal spot because it's tight enough to be fairly flat even on a windy day like today. It's headwaters are a fairly shallow rocky section of the river that is ideal for running over with the Jet. The engine fired up right off, water flowed out of the P-hole proving I did get the pump lined up with the waterline correctly. No water rushing in, good to go. At idle, the jet backed up in properly with the flow deflector in "reverse". Forward worked too. Running up the throttle brought the nose up and it wasn't coming back down. I tried a couple of different positions on the trim bar. Best was all the way down. I ran up river with just me and the deck for weight. I sat on the aft deck using a boat cushion to bridge the coaming. This direction was also up wind and I found her to be very susceptible to being blown around. It felt like we were running over the surface instead of cutting through the water. This will take some getting used to, but as the idea is to draw as little water as possible this is definitely working. Up river I was topped out at 24 mph, down river the gps was reading 28 mph. So the river must have been running 2 mph in that stretch. I took her up through some shallows and around downed trees in an area I wouldn't have been able to run the prop. At slow speeds I drew less than 6 - 7 inches. At plane it felt like it drafted less than 4" but I need a chase boat to get a true measure of how much hull is still in the water.

Back home I took the motor off and beat the railing under the motor board to allow the motor to clear the 1/4" interference. I though it was in significant before, but finding out that I need all the down trim possible made the adjustment worth making. Sunday I hope to take her out over the Ct River sections I really want to hit. More tuning and got to get some earth tone paint on her.
 
I haven't gotten her back out on the water but I've addressed the 1/8" thick coaming as far as sitting and comfort goes. The helmsman's seat was added, a section of the channel added behind the aft coaming providing a solid 3" wide seat. The side coamings got a 1X1 inch tube riveted along their tops to the outside. Still needs the boat cushion but they won't dig into you or your waders if the cushion slides out of position.
I did get her painted yesterday, but the gusty wind sure prevented any sharp transitions from one color the next. Still, she came out well enough to hunt the season and paint her right - good paint and rolled on for a serious base coat next year after striper season. The bottom is going to get an armor coating to help deal with the rock and gravel strikes.

Second season is coming fast and I've got to get comfortable running her up to the new areas I'm wanting to hunt. now where is my smallie rod? Hope the weather is good the next couple of weeks.

3" channel and 1" sq.tubes installed:

View attachment Helmsseat.JPG



Full painted boat just wish the focus was a touch better:
View attachment Spraybombcamo.JPG



Am I the only one too cheap to buy stick on numbers?
View attachment camopaintbowon.JPG

See you on the river!
Scott
 
Scott Farris said:
. The bottom is going to get an armor coating to help deal with the rock and gravel strikes.
Click to expand...

Awesome job Scott. I'll add this as you research bottom coatings. I applied Steel Flex 2000 to my 12 footer. It cured for a full 2 weeks in 60 and 70 degree weather. It is a very slick coating but I must say as I dragged the boat across the yard approx. 40 feet to put it on the saw horses for the hull paint I noticed several gouges to the metal. I retraced my steps and found only tree limbs and hard ground that I dragged the boat over. I will say I only applied one coat as I saw in several youtubes videos. Needless to say I'm less than happy. I'll do it again for next season but I'll most likely use Frog Spit after watching yet several more youtube vids unless someone has a better idea.
 
Thanks Ed,

I'm looking at Hull Speed Smart Armor, 3 coats = 1 QT rolled on. I'm not expecting to turn soft aluminum into a 500 bhn AR plate but if rocks scrape the coating off instead of the aluminum, I'll be happy. Next year project so it will be a coupe of years for a review.

Best!
Scott




 
Scott

26 mph average sounds pretty darn good. What did you get with your old rig? Couldn't be much faster than that. Looks like you accomplished every goal and then some.

Eric
 
Hi Eric,

I was bummed to read about Jeff's outboard, I hope Karma bites them hard.

Thanks for the complements, I'm extremely please how she's turning out. Since you asked (thank you,) the Starcraft rig decked and empty with the 25 hp Nissan w/o the rock hopper would hit about 25 mph. I don't ever remember checking her top speed in the 30 hp configuration and w/ rock hopper. Heavily loaded I doubt we were exceeding 20 mph.

View attachment 14underway2RIR.JPG

She's next up for overhaul. I'm planning on putting a 30hp 4 stroke Suzuki 20" shaft. This will allow me to rise the transom - totally filling in the cut down portion for a better open water boat. Not sure if I'll be able to incorporate a splash well but that's a hope. W/ rock hopper gone, she should move right along when needed.

Pics compliments of Dave Morton or Dave Trip (?) Wendell Avery is the spokes model in the forward seat. Brant sleds, decoys and loads more stuff packed in with us. Have I said how much I like decked tin boats?

View attachment 14underwaycloseupRI.JPG

Eric, I've really enjoyed your shop pictures, makes me so envious (only in a good way :^), hope you have a great season. p.s. I should have the fleet ready whenever you decide to do a DHBP hunt around the country letting all your site friends host you.
 
Scott,
Great work on the rig. I love the look of your boats with the deck. Since I'm in CT, I'll drop off a boat for you to transform for me, no rush, the north zone doesn't open up until 11/10 ha ha. You gave me lots of ideas, which is dangerous Mike.
 
Hi Mike,

Thanks! Sure just drop her off with a big check for materials, I have a great time messing with boats. And if you are interested in a SXS sneak boat hunt, I'd be up for joining you. I got an aluminum one of those too.



View attachment sideshot.JPG
 
SxS hunt sounds like fun. The only problem in my area is that you need to buy boat launch permits in many of my spots.
I know of a super secret (not) spot in North Haven we can try. (Free launch) It's been 4 years since I've been there, and it's on my short list for this year.
 
The following is a write-up supplied with the jet conversion. If I had read this first I may not have invested in the jet adapter, thinking I could use it on my Starcraft. Would I still have gone jet? Not sure as I would have been more aware of what the addition would cost me. For those who haven't read the early posting recently I ended up buying another 14-ft hull and trailer then buying a replacement 30 HP motor for the Starcraft. A smart man would have looked for a used (or new) jet boat already set up. That's not to say that I'm not very pleased with my end result but it wasn't the simple little acquisition I thought it was.

Scott

Shallow Draft Jet Drives Make Every River Longer​


SELECTING A BOAT FOR USE WITH THE OUTBOARD JET​
By Specialty Mfg. Co. 0 2035 Edison Ave. ? San Leandro, CA 94577 ? Tele. (510) 562-6049​

​
Combining the correct outboard power and boat design is the "secret" of successfully using an outboard jet to run in shallow water. Before reading this information, please read the "Outboard Jets" brochure. These two pieces of information will assist you in selecting the best combination for your needs, thereby giving you the advantages of outboard power for shallow water use.

Most important is the boat. Keep it light as possible since, unlike a propeller drive, you cannot change to a lower pitch jet drive impeller to increase load capability .

Aluminum is usually the material of choice. It is light, tough and easy to form in the proper configuration. For outboard jets, the bottom thickness can range from 1/ 16" (063) for 20-50 HP to 3/16" (.187) for motors up to 225 HP. The lighter gauge is more easily damaged whereas the heaviest gauge can be a weight problem on mid range power from 50-1OO HP .

The size and shape of the bottom is very important. The object is to ride on top of the water, which requires a good planing surface, and to float as shallow as possible when shut down. Bottom should be at least 48 inches wide and boat length at least 14 feet long.

Air entering the jet drive causes slippage, so the boat bottom needs to supply solid water, free of air, to the jet drive intake.

No one boat can satisfy every need, so choices must be made. With this thought in mind, some pros and cons of various boat types are noted below.

A flat bottom boat runs shallower than a "V" bottom but slides on the turns more. A "V" bottom splits off air bubbles before they reach the jet intake. A flat bottom carries bubbles straight back.

The boat on the inside page of the brochure is an aluminum flat bottom with a 48-inch (4ft) bottom (45HP) and 14ft. overall. This design works well but will ingest some air when running with the wind in a chop. This can be helped by the use of intake fin side skirts.

A slight "V" of 6-10 degrees dead rise will enhance jet boat handling. Deep "V" is not desirable for the Outboard Jet, not just because of increased draft and drag, but because the Outboard Jet needs a flat apron of water about 10" wide,leaving the hull on which to set the leading edge of the jet intake, to minimize air intake and frontal drag. The dead rise should be fairly constant and not increase to a deep forefoot at the bow. A deep forefoot can cause spin out on a sharp turn.

Keels can be a problem, introducing air into the jet intake. Center keels vary in size and may introduce air. If this is suspected, the keel should be removed 2-3 feet forward of the transom. Other keel arrangements which tend to funnel air to the jet intake should be avoided.

The chines of the boat, where the sides meet the bottom, should be sharp. Round chimes tend to suck the boat down in the water and cause drag.

A properly designed tunnel, combined with a slight V bottom hull can greatly enhance jet boat performance. It should raise the motor 2-3 inches and place the heel of the jet intake flush or slightly above the bottom of the boat. A jet typically does not work well with a flat bottom boat due to air ingestion. It's imperative that the hull is designed correctly with the tunnel for the boat to operate properly.

The tunnel needs to be just large enough to feed the jet drive its water requirements. A tunnel that is longer, wider or deeper than necessary wastes power in lifting excess water, tends to suck the stern down when planing and sits deeper in the water at rest due to lost buoyancy.

The top of the tunnel width should be about 1 3/4 times the width of the jet drive water intake. The tunnel length does not have to be longer than about 2 1/2 times the water intake width.

inflatables are light, easy to transport, bounce off the rocks nicely but due to the flexible nature of their bottom they trap and introduce air into the jet intake. Steering is squirrely when running light and in crosswinds. Even so, we get calls from our customers who are very happy with their inflatables.

A rigid hull inflatable on the other hand cannot be folded to fit inside your car but steers better and provides solid water to the intake. Unfortunately, the hulls presently available have more than 10 degrees of dead rise.

Pontoon boats do not provide a defined height apron of water ahead of the jet intake. The water level between the pontoons varies with speed and load carried. It is necessary to build an inclined plane ahead of the jet intake attached to the motor mount, about 16" wide inclined at about 15 degrees with the leading edge above water level, fully loaded at rest, trailing edge lined up with the leading edge of the jet intake.

So much for boats. now about power. There is about a 30% power loss when converting to our jet drive. A suitable outboard jet boat carrying an average load will provide about 80% of propeller speeds. It is important to decide what load you want to carry, how many people, gear, fuel, etc. and add the weight of the boat, motor and battery. Look up this gross weight on the chart in the Outboard Jets brochure to determine the minimum HP you need. The chart HP is power head horsepower.

It's important that the boat-motor combination plane the boat quickly. Planing would normally be in the mid 20 MPH range and up. This is necessary for optimum jet performance and shallow water running. At low RPM, when the boat is not planing, you would need about 12 inches of clearance between the bottom of the jet and river bed to maneuver.

If at all possible, please, before you buy an outboard jet boat, go for a ride and look for these characteristics. Does the boat plane quickly and not cavitate easily (listen to the motor for the change in RPM's) a destructive and negative performance trait. Will the boat maneuver through obstacles typically found in your environment without breaking loose or skating? Is handling predictable? Poor performance will show up in a jet boat taking a long time to get up on a plane, breaking loose early in cornering and cavitation.

The advantages of the Outboard Jet boat include maximum space inside the boat while still having the ability to operate in less than 6" of water, relative ease of cleaning out a clogged pump and adjustment for wear on the impeller and intake liner.

So, select a suitable boat with sufficient HP to handle your total weight, then enjoy fishing and hunting in areas you couldn't reach before!

May 15, 1997
By Specialty Mfg. Co. 0 2035 Edison Ave. ? San Leandro, CA 94577 ? Tele. (510) 562-6049
 
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