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Trim Tab?

I

instigator

Active member
Hello everyone, I was wondering if someone could be so knid to tell me.

Where is the cheapest place to by a trim tab? How much? Even if someone had a used one in good shape? I was looking at a Lenco? Saw one online at Hook & Hook for $209.00 with no switch however they wouldn't respond to my email on availabilty.

Thanks in advance for reading this post and for any replies I receive.

All the Very Best,
Mike
 
No place is cheap but Floral City Airboat Company has them. A complete set with switch and all is $240. http://www.airboatfl.com/eshopitems_cat_4120-41258.Trim_Tabs_And_Parts.htm
 
I bought mine off ebay. Another good place is a boat salvage yard or a boat salavage place on the internet.
 
In my Opinon they don't make a good trim tab for an Airboat. We are rough on them all. Like forgetting to raise it when your on dry. But if you go Cheap, Cheap is what you get. Most everyone that uses one has a Lenco.
 
I am in davie and my buddy just told me he has a bran new one and I think he wants @100 bucks. Pm me if you want his number.
 
I have run dual lenco for years and I have done everything you can thing of and I have never broke one.
 
I have two questions, first on an aluminum boat, how does the trim tab fit, considering there is a peice of aluminum extending from the bottom of the hull and the trim tabs look like they need to mount on a vertical surface that is at the very back of the boat....?????


Second question, it seems like whenever a boat is porpoising folks talk about lowering the back of the motor to lower the nose, or moving weight forward, like the fuel tank, batteries or a big beer cooler or whatever. BUt no one ever talks about going the other way, seems to me that a porpoise is caused by the wetted area moving too far back and the boat becomes a lever with too much weight in the front, and drops. Then it starts over with the wetted area moving back.. SO you have two choices,, hold the front down or put more weight inthe back and hold the front up.. Think about it first and then tell me why I am wrong.. weight the nose down, or hold the nose up??
 
Norris,

I believe you are missing the bigger picture when you look at the weight distibution first and the engine attitude (angle) second.

First of all we have to assume there are no problems with the hull that will keep it from running as it should. Remeber that in both cases, (engine attitude and weight) you are talking about fine tuning. Ie. If something is way out of whack, neither is going to solve the problem.
Norris said:
. . . whenever a boat is porpoising folks talk about lowering the back of the motor to lower the nose, or moving weight forward, like the fuel tank, batteries or a big beer cooler or whatever. BUt no one ever talks about going the other way . . .
Click to expand...
There is more than one way to view the answer to your question.
Most obviously and importantly: 1) if the back of the motor is already to high it will cause the bow to plow, not porpoise . . . and 2) if there is already to much weight forward it will cause the bow to plow, not propoise. Additionally, while there may be room to move rigging forward if need be, it seldom can moved back because the prop is generally lower than the top of the transom. Hence, the neccessity of moving everything else to adjust weight if need be.

When nearly any boat (airboat, skiboat, sportboat, offshoreboat) has a straight, true hull and is porposing it is because the attitude of the propulsion system is lifting the bow beyond the capability of the drive system to hold it up there. Then it falls back down, bounces . . . and the process starts over again. If you trim the attitude of the propulsion system down just enough to prevent this porpoising, it will be running at its best attitude possible given the propulsion system being used.

The most obvious example of this would be power trim on an outboard motor or an I/O setup. Porpoise, trim down OR Plow, trim up. With inboard engines and airboats this is not possible so then you have to resort to the infamous "Trim Tab" to accomplish this adjustment as there is no "power trim" system available. :?

Then you end up back where we started . . . . A) staight hull, B) engine attitude, C) weight distribution. :wink:

Hope that all made sense.

Deano
 
Great job Deano!!!!!!

Couldn't of said it better.

I actually already tried to move the back of the engine up. It helped with the porposing, which was Great! However like Newton's law "for every action is a reaction". Well the same for me I eliminated most of the porposing however I could NOT push dry worth a damn and the boat was slower. So for my cause it seems the need for a trim tab is due. I hate trim tabs, mostly because I love to play so much and doing spin arounds.

All the Very Best,
Mike
 
jimmyflfr said:
I am in davie and my buddy just told me he has a bran new one and I think he wants @100 bucks. Pm me if you want his number.
Click to expand...


Hey Jimmy, I pm'd you. Yes I'm Very interested in your buddies trim tab. If you wish please pm me with his #.

All the Best Jimmy and thanks again,
Mike
 
Norris said:
I have two questions, first on an aluminum boat, how does the trim tab fit, considering there is a peice of aluminum extending from the bottom of the hull and the trim tabs look like they need to mount on a vertical surface that is at the very back of the boat....?????


Second question, it seems like whenever a boat is porpoising folks talk about lowering the back of the motor to lower the nose, or moving weight forward, like the fuel tank, batteries or a big beer cooler or whatever. BUt no one ever talks about going the other way, seems to me that a porpoise is caused by the wetted area moving too far back and the boat becomes a lever with too much weight in the front, and drops. Then it starts over with the wetted area moving back.. SO you have two choices,, hold the front down or put more weight inthe back and hold the front up.. Think about it first and then tell me why I am wrong.. weight the nose down, or hold the nose up??
Click to expand...


Here is how mine are mounted.

IMG00091.jpg
 
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