confused on using trim tabs?

wajajaja02

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this is how my used boat came to me.
My trim tab switches, are wired oriented correctly port and starboard, but the up position lowered the tab and down raises them. seems backwards to me.

Also, if the boat is listing to port, do you lower the tab to create lift off the tab . or both tabs to help get out of the hole, do tab down create lift or drag.
common sense and physics aren't always what they seem.

thanks.
 

skargo

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Re: confused on using trim tabs?

Bow down the tabs are extended(down), bow up they are retracted(up).

If your boat is listing to port, you either want the port tab up some, or the starboard tab down some. I use split second taps on my switches, and wait a couple seconds for the boat to respond.
 

redone4x4

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Re: confused on using trim tabs?

sounds like the up position is raising the bow up. maybe thats what they meant when they installed them. If the tabs lower down, the bow will come up and so on. you could probably switch it the other way if you wanted to. tab down should be lifting the boat out of the water if im not mistaken.
 

skargo

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Re: confused on using trim tabs?

sounds like the up position is raising the bow up. maybe thats what they meant when they installed them. If the tabs lower down, the bow will come up and so on. you could probably switch it the other way if you wanted to. tab down should be lifting the boat out of the water if im not mistaken.
:confused:
If the tabs lower down, the bow will go down.
 

wajajaja02

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Re: confused on using trim tabs?

I just figure out what the tab are doing, so now when I'm on the water I ll learn the reaction of what i do. I see your point in reference to raising the bow to the switch position, seemed backward or at least confusing but isn't boating rules anyway.
 

redone4x4

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Re: confused on using trim tabs?

yes, you are right skargo, sorry. the tabs lift the stern up, pushing the bow down. I stand corrected. his are just wired backwards then.
 

skargo

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Re: confused on using trim tabs?

yes, you are right skargo, sorry. the tabs lift the stern up, pushing the bow down. I stand corrected. his are just wired backwards then.

I had to think about it. :D
 

wajajaja02

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Re: confused on using trim tabs?

pulled the tab switch, its a Bennett , and its wired correctly, pressing up is labeled "bow down" which lowers the tab below the the boat. so now I know what I'm doing.
 

QC

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Re: confused on using trim tabs?

Yes, properly wired trim tabs are designed to manipulate the bow, not the tabs . . . Huh? Backwards is right. So when you push the Starboard tab switch "up" it puts the port tab down, forcing the starboard bow down . . . Still confused? The way I teach new operators of tabs is to put your hands out in front of you with your palms facing away. Then think of your hands and the switches simultaneously, and then "push" the starboard hand and bow down, that's the correct motion on the switch ;)
 

Home Cookin'

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Re: confused on using trim tabs?

<<<So when you push the Starboard tab switch "up" it puts the port tab down, forcing the starboard bow down . .>>>

QC--do you mean: when you push the starboard tab up, it lowers the port tab, which lowers the port bow and raises the starboard bow on balance?
Anyway it's all backwards and my used boat was wired backwards--and I never had tabs before. So after initial trips of trying to go opposite of opposite I rewired them right (that is backwards!) so now the Lenco switch label is the guide: I push the starboard switch up to raise the starboard bow, and try not to think about what's going on behind me!
 

skargo

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Re: confused on using trim tabs?

pulled the tab switch, its a Bennett , and its wired correctly, pressing up is labeled "bow down" which lowers the tab below the the boat. so now I know what I'm doing.

That's how mine are wired. Just don't push one down and one up at the same time, or if you do, make sure you have a 20a fuse handy. :D
 

QC

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Re: confused on using trim tabs?

<<<So when you push the Starboard tab switch "up" it puts the port tab down, forcing the starboard bow down . .>>>

QC--do you mean: when you push the starboard tab up, it lowers the port tab, which lowers the port bow and raises the starboard bow on balance?
No. port tab goes down, which lifts the port stern and conversely pushes the starboard bow down. Opposite "corner" of the tab that is manipulated is where the reaction occurs, and ultimately why the switches are reversed.
 

wajajaja02

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Re: confused on using trim tabs?

push the starboard switch up(bow down) and the starboard tab responds downward. and so does the port switch respectively,
I was confused on switch to tab vs switch to reaction
 

QC

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Re: confused on using trim tabs?

push the starboard switch up(bow down) and the starboard tab responds downward.
No . . . If wired as per Bennett and most other tabs, port tab goes down forcing starboard bow down.

Try this: Bennett Simulator

Works okay . . . But I couldn't steer the boat without forcing one tab down to get her to straighten out. With the simulator straight I could see the results pretty easily. One good way to adjust them is by noting where the splash falls off to the side of the boat. This is evident in the simulator as well.

Also, if you PM me an email addy I'll send back the Bennett Operations Manual . . .
 

Home Cookin'

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Re: confused on using trim tabs?

QC I think we're saying the same thing but it's making my head hurt. Now that I'm wired so that the labels on the switch say what will happen, I'm not thinknig about it no mo'.
It's like trailering: I've been backing trailers for 36 years and I can only do it b/c I can't describe what I'm doing. I'm better off not using a mirror but looking over my right shoulder and not looking at what my hands are doing. The only way I can "help" someone else is to reach in the window and turn the wheel myself!
The hardest things I'm having on learning to use the tabs is (1) the reaction time and (2) coordinating the motor tilt with the tabs. Also I'm used to "bow up" for chop from flat boats and now it's "bow down" for the deep V.
Old dog new tricks.
 

26aftcab454

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Re: confused on using trim tabs?

my tabs are factory labled / stamped on the plate:

TOP tabs say LOWER and they lower the tab=lower the bow.

BOTTOM tabs say RAISE and they raise the tab= raise the bow.

works for me:cool:
 

QC

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Re: confused on using trim tabs?

I've learned to love the way they are switched, but . . . it is really hard for newbies to catch on. Opposite the drive trim button for up down, so counter intuitive.
 

skargo

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Re: confused on using trim tabs?

I've learned to love the way they are switched, but . . . it is really hard for newbies to catch on. Opposite the drive trim button for up down, so counter intuitive.

Damn, never realized that. Thanks a lot, I'll probably get all confused out on the water now. :D
 

wajajaja02

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Apr 21, 2008
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Re: confused on using trim tabs?

played with the tab demo, cool, will go out and re examine my tabs to be sure if the starboard switch works the port tab, I dont think so. with the manual, I should be able to id the wiring, the switch terminals are very unique, and Im a retired telephone switch-man.
 
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