Glen-L.com

What are y'alls opinions on adding a motor pod to a 20 foot Snake Shooter?
https://www.boatdesigns.com/products.asp?dept=878
http://glen-l.com/designs/hankinson/slither-snakeshtr.html
http://glen-l.com/designs/hankinson/slither-snake-pho-1.html

Not sure of the motor of choice. Likely it will be around 150 horse, and ideally, it would be a newer Etec or Honda 4 stroke (leaning towards the Etec) but considering I am a high school student, thereby not having a very prosperous job, I may end up with an older OMC V6, with a kicker for trolling. I do like the idea of the motor pod, mostly for the space added inside the vessel. Now, another option would be something like an OMC Seadrive, but those aren't popular, so I would be in a heap of trouble if I wanted/needed to replace it.

Is the Snake Shooter a vessel that is capable of holding a setback pod, or should I stick with the motor well, and standard transom?

what do you mean by a motor pod? What is the 'pod' you describe.

Look at picture 16 in this post.
http://www.aluminumalloyboats.com/viewtopic.php?f=6&t=693

Here is the Pacific 2025, that features that.
http://pacificboats.com/pacboats_003.htm

I'm with Ken here. I don't know what a motor pod is either, but I take it from the photos that it is this thing that sets the motor way back from the stern. So my question is, what is the advantage of doing it this way? Obviously, it gives you more room in the boat itself but other than, what's up with it?

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Isn't it amazing!! The person that never has the fortitude to pursue his own dreams, will be the first to try and discourage you from pursuing yours.

I could explain, but there is no real need to rewrite what has been written, to a more descriptive level than I could have done so.
http://continuouswave.com/whaler/reference/engineBrackets.html

Thats more commonly called a bracket. A Outboard bracket.
Its the latest fad in outboards. What happens when a big fish decides to take the line around the back of the boat........then what do you do?

That is a trade off. One I am willing to risk. Do y'all think this hull is capable of that though? What about those in transom doors, and make the bracket/pod whatever you want to call it wider, with a step on either side. That would make entry when its on the trailer, and entry from some of our bad docks easier. I know the combination of both of those may be pushing the limits of this design, but I figured y'all might have some good opinions.

I think that is reasonable, since a 150 2 stroke is half the weight of the allowed I/O. The lighter weight ouyboard moved farther aft would be close to the original CG. Gosh, do the math to get a hard figure on the CG.

My concern wasn't so much the CG as opposed to the structural integrity of the design. Many of the alloy hulls I have seen with the pods/brackets on the transom use a different building technique than these. This hull uses the system of transverse stringers, with longitudinal stiffeners connecting them all. The frame of this boat is made on a jig, and the plating (or sheeting in this case) is added afterwards. Many that I see with brackets/pods involve a different building method. They put the plating in a jig, and build the frame inside the already formed plating. These rigs tend to also have more longitudinal stringers, as opposed to the system of longitudinal stiffeners.

I wasn't sure how this hull design would cope with the added stress of the engine being put on a setback, or if it would start to develop a hook, or fatigue in other ways.

bassboy1,

The Snake is a "sled" hull with a constant deadrise and parallel chines aft the master section. This hull is used for jets in many cases because of the low V chine tripping is not as prevalent and the speed is maximized even though turning is a bit wide compared to a tapered chine model of the same hull.

These boats are pretty commonly river runners as they don' t have much V in the forward sections and slam in a head sea.

As far as moving the outboard aft, it will be fine and the hull will still move well. What kens is discussing is to figure your balance changes and keep the original design's CG where is was.

When you build the boat, don't mount the tanks, use two, outboard along the gunwales, and don't anchor them-wait for the builder's launch. Mount the leg and float the hull and slide the tanks forward until she lays flat enough to live with. That is a 'eyeball' method of balancing a sled hull. You can use any of the gear in the cockpit to to this same thing; trim by the bow.

Make sure you lean the transom an extra 10 degrees AFT when using a bracket and make the top of the transom is LOWER than 21' (VERTICAL) to the planing bottom extended line. The wake will climb aft the bottom and that will bury the cav plate and you won't get to full R's, loosing tons of power while still burning more than you need in fuel. Most bracket installations need some shims to get the leg UP higher than the hard top plate. I build them lower and make a set of shims to test them with and then just TIG tack the shims into a stack and leave them. The real engine mount on an outboard is the four through-bolts not the transom clamp.

Sleds are very forgiving because they're not tapered (at the chines) and there is no rise to the keel or chines aft the master section. So the extra wt. aft will just squat the original design, which you could live with or adjust by trimming the console, batteries, fuel and gear a bit forward. It will still lay down and plane if you can get the outboard trimmed under enough.

Welded aluminum boats don't matter if they're framed with transverses, as Mr. Hankinson has done on many of his designs, or if they're long-wise framed like the Pacific and Black lab skiffs. Once either boat is welded the whole hull is one piece of the "Miracle Metal".

Use 3/16" for the bracket up to 100 HP and 1/4" above that. If the Snake's stern doesn't have any provision for a pair of knees to carry the transom to the longs, just add some full ht knees lapping the main longs or original timbers and that will transfer the moment of the bracket to the main timbers and the hull will be fine.

cheers,

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Kevin Morin

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Wood lasts generations.

Wow, boob drive.

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Isn't it amazing!! The person that never has the fortitude to pursue his own dreams, will be the first to try and discourage you from pursuing yours.

Interesting. However, I do plan to keep with a conventional outboard for this rig.

Wonderful explanation by Kevin. In Northern California, they tend to refer to these as off-shore platforms. The only reason I can see to have one on a lake or river boat is so you have some place to put that 60 quart cooler. The purpose is, as Kevin eluded to, is to keep the lower unit and prop in the water when experiencing other than flat calm waters.

The sponson style units came along later and extended the boat hull allowing you to retain the CB of the boat without needing to re-arrange everthing inside. Full width sponsons are often used when running dual or tripple engine setups.

On the snake shooter I believe you would be better served keeping the engine closer to the transom and running a minimal offset (5-6") hydraulic jackplate such as the CMC PL-65. This plate has a 6" travel and can help you find that sweet spot for optimum performance and fuel efficency. A side benefit is that you can change a motor out in about 15 minutes.

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Steve Schefer
Santa Rosa, Ca.

New Years Resoluiton - Never leave something for someone else to do when I should be doing it myself.