Finally Finished, 13 ft Skiff

[Cadence]

To be an ass, Take Snapper with you. Can you move the tank forward into the bow?

[HopCar]

Cadence, I was thinking of taking someone a lot prettier than Snapper to use as ballast. Yes, I will move the tank forward. I don't think that will solve the problem completely but it would help. It's not a big issue as I won't run the boat by myself often anyway.

[Cadence]

Originally Posted by HopCar

Cadence, I was thinking of taking someone a lot prettier than Snapper to use as ballast. Yes, I will move the tank forward. I don't think that will solve the problem completely but it would help. It's not a big issue as I won't run the boat by myself often anyway.

Don't move the tank. Dump Snapper and take the good looking babe.

Works for me.

[HopCar]

Now you're thinking!

[FlyingCloud1937]

Hopcar,

I'm thinking bigger issues are not enough buoyancy aft. Most likely when Glen-L rated the hp, that was a 2 cycle outboard much lighter then the 4 stroke Lier.

With the driver aft it compounds, so you are going to have to be very careful of your follow up wake. That alone tends to say move driver forward with a tiller extension.

Lloyd

Originally Posted by HopCar

Cheechako, I'm thinking fixed tabs or spring loaded tabs. You're right I want to keep it simple. There is a battery and alternator on the engine and I'm sure I could borrow power from that to run some Lenco tabs, but I'd rather not.

[a64pilot]

How about a "stick steer". I've a little 14' boat with a 25 Mariner that is stick steer, balanced out real well

[manitu]

Is the motor trimmed all the way in? and still not enough lift in the back?
If you need more lift in the rear throughout the speed-range, a wing on the drive or fixed wing on the hull is the way to go.

But usually you cant get both lift in the rear to get the boat planing, and then the bow to lift out of the water for top speed

For that you need spring-loaded tabs. I only know of one brand called smart-tabs, here in norway at least.


They will create the lift you need at low speed, and then slowly retract towards top speed, depending on the spring you choose.

Did wonders for my 10' pioneer "speed" dinghy.

..manitu

[a64pilot]

You know I wonder if homemade tabs with gas struts would work? You can get the struts in all kinds of lengths and pressures, even SS ones, but I have no idea how well they would hold up in salt water.

[Suijin]

Originally Posted by HopCar

What do you guys have against trim tabs?

Nothing, I really like electric trim tabs, get a boat on plane quicker and keep the bow down when climbing on plane and you can back them out when less of them is needed.
Truthfully I don't have an answer why you see so many fins on small boats, but not tabs, I have no experieice with fixed tabs either, only electric ones.

Tabs are going to require cutting a bunch of holes in the boat, to mount the tabs and run the wires or hydraulic lines. IMHO Bennet tabs are the best, but they are hydraulic and maybe more than you want to get into for a boat that size. The one really nice benefit of tabs is you can level the boat exactly how you please for the load and sea state, and even level the boat side to side in a stiff crosswind.

Me? I'd start with a 3' length of PVC tubing as a tiller extension. Cut slots in one end and slide it over the handle, tighten with a hose clamp...drill a 1" hole if the kill button is on the end of the tiller to get to it. It's $5 and 30 minutes worth of work and might be what you need.

Doelfins and the like work really well on smaller lighter boats. It's a less intrusive and complicated solution than trim tabs, for sure, and will likely give you almost the same ride.

[HopCar]

It sounds like all of you guys understand the problem. Too much weight aft and not enough lift. All of the suggested solutions should work.

Tiller extension moves weight forward. It's cheap and easy and it works.
Draw backs are it limits maneuverability at low speeds and it is difficult to reach the shifter.

Fin on lower unit increases lift. Should also work if done in combination with moving tank forward. The one time I tried a fin I didn't much like it and eventually replaced it with active tabs. That was on a larger boat. Might be different on this boat.

Fixed trim tabs increase lift by extending the bottom of the boat. Should work but I've never used them. Spring loaded tabs are similar but might be even more effective.
Requires a lot of screw holes in the transom but I've got 5200 and I'm not afraid to use it.

Active trim tabs would be my choice except for the increased complexity. I know they work and they would allow me to push the bow down in a chop so the V is hitting the waves instead of the flat bottom.

Lots of choices and no rush to decide. I'll probably try the tiller extension first as it is quick and easy. I don't think that will be the solution as the center seat is pretty far forward.

[Scout 30]

Weight distribution in a skiff is critical so the first thing that I always do is add a tiller extension. Adding fins or tabs to try to compensate for too much weight in the stern will create drag & slow your boat down as well as decrease your range. Plus, it still won't handle like it would if it were properly balanced.

[Roy M]

Nice boat, HopCar! I have a Whale Tail (Davis) sitting on my truck's back seat waiting for its installation of my Lehr 15. Then, I got a deal on a PropGuard, which is also sitting on the back seat. My plan is to take my RIB from my slip, out to the measured mile, do about ten passes, noting the elapsed time and checking the portable GPS on my smartphone for speed, then return to the slip and take the propane tank (Ragasco composite, 33#) to get it filled to see how much consumption at the two transits and the wide-open throttle runs on the measured mile. Then, with a fresh bottle, install the Whale Tail and do the same. Lastly, I'll add the PropGuard to see if there is any significant deterioration in performance.

I guess that isn't lastly, because I will then install the little hour meter/tachometer that wires into the spark plug wires, and do a series of measured miles at different RPMs to see if there is a significant difference in fuel consumption using the Whale Tail and PropGuard.

I really want a PropGuard, even if it cuts into my fuel economy. I've personally seen the effects of a spinning prop versus a human body in the water. The Seal Teams and Coast Guard are now using them regularly on their RIBs.

I suppose I could also see what effect just the PropGuard has, without the Whale Tail. The makers claim improved channeling and trim with it, but I'll see and report. Right now I'm in the final stages of painting my decks and completing the dinghy launch system (with chocks under the RIB for the extra propane tanks). Pictures later.

[Scout 30]

It would be very interesting to hear how your boat responds to the PropGuard. According to their website performance & handling should be enhanced & no whale tail should be required. In fact, since they both attach to the cavitation plate you may not be able to install both.

[HopCar]

Hi Roy, I was going to PM you and point you to this thread. I'm glad you found it.
I'll be interested in the results of your tests as well. I'll keep you informed about what I'm doing with my Lehr engines.


You've got the electric start don't you? Does yours have a start button or a key?
The first ones I saw came with a start button but my came with a keyed switch. I'm not sure but I think I'd be a little happier with just a button.


That little battery under the cover is amazing. It really spins that engine.


I was very pleased with the ease of starting and the power the first time I tried it. I'm glad I went with the 15 instead of the 9.9.


Lehr is now talking of a 25 hp propane engine.

[Roy M]

Mine has the key switch. The battery is a 4 aH unit that I would like to couple to a slightly larger battery, perhaps using a combiner, so I can someday run some onboard electronics and have a more powerful VHF radio and 6 dB whip antenna. I'm also thinking of making an arch to hold the antenna and stow some other stuff. My plan is to use the RIB as a scout boat to check out reef entrances, explore up rivers and fjords, and to get places fast when I need to. I love the 15. The prop guard will fit on the underside of the cavitation plate, leaving space for the zinc plate. The Whale Tail fits on top of the cav plate, so I can use the same bolt holes to attach either or both, depending on the outcome of the testing.