Jersey Skiff Build - Natural High

[M3Bluegsr]

I'm starting to build a Jersey Skiff for a friend, that is a model of his dad's former boat. A little different from what I usually build, but should be a fun vintage project. Here is the description from my friend:

"Time to get nostalgic, the older skiff pictures was my dad’s original bender hull NJ Speed Skiff he built back in the early 80’s when I was a kid. The top picture is a hull he purchased, had painted to match his original, but never built it."

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[M3Bluegsr]

Here is the model skiff, it was made by Specialty Engineering Inc in Lanoka Harbor, NJ. Originally calls for a .40 nitro, but will be going with electric since he already has FE models. I've included a letter from the builder when he first purchased, describing how to outfit the model.

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[M3Bluegsr]

Parts arrived today, thanks OSE. Going TP 4060 - 1350kv, Speedmaster mono strut, OSE rudder, Seaking 180A esc, and OSE adjustable trim tabs.
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How it sits now
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This is how I plan on doing the hardware setup, any suggestions on submerged prop size and depth?
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[M3Bluegsr]

TFL Motor Mount
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Found Center, referenced bottom to find level, and attached some of the hardware. The deck is about 1/4" off center. At first I thought I measured wrong, but was easy to see, once I confirmed measurements.
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[M3Bluegsr]

Strut on, when in the full up position stuffing tube can almost touch bottom of hull. Should give me enough adjustability.
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Stuffing tube annealed and bent with tube bender.
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Doing final alignment before glassing in.
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[785boats]

Looks great.
I love the skiffs & crackerboxes. Full size racing looks like a blast.
Our club used to race 1/10th crackerboxes. Heaps of fun. But we had straight drive shafts with the prop under the transom, so I can't help with the appropriate prop depth or size for your setup.
Someone will though, I'm sure.

[M3Bluegsr]

Thank you, the owners of a full size skiff must be nuts to drive these things.. but it does look like a wild ride.

For the strut and prop depth, I researched similar flat bottom boats and copied how they did the setup. I ended up bottoming out the strut adjustment, then made the stuffing tube almost touch the boat bottom, and that was the height the bracket was mounted to transom. This gives me strut adjustment from touching boat bottom, to full extension of the strut. If that is not enough I could always open slot in strut for more adjustment, but should be a good starting point. As far as how deep it should be with a certain prop, I will probably have to experiment.

[M3Bluegsr]

A little free time, so I repaired two of the original hatch tabs that came un-glued with epoxy. The other two were still very secure, so instead of tearing out the two good tabs, I repaired the others and will tie in additional framing later.
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2 Strips of fiberglass to hold motor mount in, will clean up once hardened. Battery trays will be next.
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With motor in place, I also cut shaft to length and did the exterior servo linkage. Just have to drill for water inlet.
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[M3Bluegsr]

Making the battery tray bracket templates.
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Brackets will allow 1/8" clearance on battery sides/bottom to run straps.
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All Parts Cut.
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Assembled. I will seal the wood and then laminate with CF vinyl to match motor mount.
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Servo bracket made, time to seal and then paint.
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[properchopper]

Top Secret : Jersey Skiffs are the most fun you can have in FE. Fast and barely in control - they go up on their sides in the turns [ prop digs in, unvents/hull bounces down/prop digs in again/up on the rail/unvents again and so on]. The prop depth is important for sure [and I've not discovered the magic formula yet BTW]. The D19 gas skiffs stay on the rail all through the turn now - took lots of tuning but I'm not there yet with my FE skiff. Seems that at your chosen KV you'd be running 6S - the TP motor is a powerhouse but I'd start small with the prop given that it's submerged. Maybe an X442 to start with. Good luck

my skiff:

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Skiff Race at Winter Warmups - Both contestants were given field sobriety tests after this one

https://www.youtube.com/watch?v=RP0kDxAFCJM

[M3Bluegsr]

Properchopper: I looked through several of your skiff threads / videos for a basis on this model. Not many people have posted about these, but your thread was helpful and they are fun to watch in action.

You are correct on the KV, we will be running 6S due to my friend already having battery packs for a Zelos Twin. The skiff is being setup with an option to run 2 or 4 - 3s 5000mah packs. I have one / will start with the X442, I always try to start with a small prop and work up with electrics. It was hard to determine the load dynamics/relationship of submerged vs surface piercing props, had to guesstimating a bit. With two blades in water vs one, is load doubled, or does cavitation or another effect play a part and reduce the load etc?

I did over spec the motor watts (power) a bit, but I was concerned with the mass of this model. At less than 33", it is close to 6.5lbs with just hardware attached. Still have to add the mass of motor, hatches and parts, and batteries. Do you know or could you tell me the weight of your bare skiff hull? Do you have a normal overhead on the speed control, or add additional to cover the amp spikes when prop loads/unloads in corners?

[properchopper]

I don't have the bare hull weight. Can't find it on the Aero site either BUT my take is that these hulls like weight to minimize their tendency to bob/bounce (they're essentially flatbottoms). I've only run mine with 1500KV or 1800KV spec motors & smaller 80A or 120A ESC's which I usually have one or two extra caps on just for good luck One thing I've noticed is that if they are rigged too noseheavy the nose will dig in after a bounce and it will dart off course !

[M3Bluegsr]

Good to know that symptom of CG off! It should be an interesting setup with a little more power and weight to better keep it planted, most I have seen run your same setup.

Here is a link I came across on this forum who's skiff seems to run well..

[M3Bluegsr]

Sealed and laminated battery tray.
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Battery trays in
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[M3Bluegsr]

I cut rear bulkhead to fit for batteries and wires. Need to clean up a bit, I will paint bulkhead black where the two battery trays meet after I seal the wood.
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Starting on the hatch templates, I'll incorporate a dash panel and two seats in rear hatch. He can choose the drivers and what gauge decals on dash panel.
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