Smart tabs–what the heck – page 3 – the hull truth – boating and fishing forum v gashi kenga e zagrebit

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The reason they are flush with the hull at planing speeds is that the water is pushing them up and that is called drag. Trim tabs of any type operate by increasing drag…period. A real tab can be fully retracted out of the water at cruise if desired. These cant. Theres nothing free here….its all tradeoffs. I am not saying that is not a cost effective option for some boaters but, nobody should be saying there are no tradeoffs. The lift the transom by increasing drag.

I have a very very fast 13′ tunnel hull boat that has a DoelFin Hydrofoil. People probably look at it and think why would anyone have one of thise cheap things on a race boat. The reason is it allows my to get up on plane with a "over hub exhuast" type propeller (cleaver or chopper style). At cruise it is 3-4" completely out of the water. The tradeoff is it offers no benifit once under way becasue it is out of the water. Its all a matter of tradeoffs. Cost, effectiveness, drag, etc. Just want to educate potential readers that these things are not magic.

There is a whole lot of bad info on the first page alone of this thread. Comments that are completely wrong (like a boat with a hook in the hull needs tabs to lift the bow). None of these products can lift the bow. I am not knocking the product as I see an application for it and lots of happy customers. Just pointing out the reality of how they work. Cant change physics now matter how inexpensive they are

The reason they are flush with the hull at planing speeds is that the water is pushing them up and that is called drag. Trim tabs of any type operate by increasing drag…period. A real tab can be fully retracted out of the water at cruise if desired. These cant. Theres nothing free here….its all tradeoffs. I am not saying that is not a cost effective option for some boaters but, nobody should be saying there are no tradeoffs. The lift the transom by increasing drag.

I have a very very fast 13′ tunnel hull boat that has a doelfin hydrofoil. People probably look at it and think why would anyone have one of thise cheap things on a race boat. The reason is it allows my to get up on plane with a "over hub exhuast" type propeller (cleaver or chopper style). At cruise it is 3-4" completely out of the water. The tradeoff is it offers no benifit once under way becasue it is out of the water. Its all a matter of tradeoffs. Cost, effectiveness, drag, etc. Just want to educate potential readers that these things are not magic.

There is a whole lot of bad info on the first page alone of this thread. Comments that are completely wrong (like a boat with a hook in the hull needs tabs to lift the bow). None of these products can lift the bow. I am not knocking the product as i see an application for it and lots of happy customers. Just pointing out the reality of how they work. Cant change physics now matter how inexpensive they are not looking to argue, but adding the smarttabs allowed me to use the motor trim more effectively, which optimizes hull orientation to the water, which was near impossible before due to the boats desire to porpoise.

Your tunnel hull (dual hull) may respond well to the "fin" but i would not want to be in a single hull boat that leaves a wake and when it comes down have one side of that fin catch first. Same idea why hard cornering with the "fin" can be dangerous.

I just don’t understand at all the use of gas struts/springs on these things so as to allow them to have the exact opposite movement as what would be most desireable . If you aren’t going to have them user adjustable underway it would be better to have them solidly stabilized instead of giving up under higher load when they should be pushing farther down.

Going from rest to plane they will reduce effective tab under the initial load then deploy near fully when needed less. If wind blows from one side , or a passenger shifts to one side and boat attitude leans to that side, the low side "Smart" tab will tend to compress the spring and tab will raise, while the high side tab would extend towards it’s limit. That’s kind of dangerous crazy, and very Un Smart.. And downsea the tabs will again tend push the bow down to extend to their limit as the bow stuffs when they should have been retracted. Yikes. When backing the boat in reverse I would expect they will always shovel because they can’t be retracted the way most us know to do with ours. Bad for tabs and O/B’s & transom cutouts.

Yes, of course they will aid quicker hole shot to plane due to extending effective hull length without any appreciable weight gain, but I would think welding the struts to the "dialed in " length would work better & be marginally safer, ….and user-adjustable tabs like Bennetts , much much better & safer overall.

The only thing "smart" I see in that is in the marketing that came up with the seemingly misleading name, apparently encouraging prospective purchasers they magically automatically react the opposite way they actually do . Would you buy them if they were called Silly Tabs or Danger Tabs? 😀

I readily admit I’ve never knowingly been on a "Smart-Tab"-ed boat, but I just don’t "get" these things. Can anyone please explain a rational benefit of the springs?The spring loaded actuator limits the amount of pressure applied. A rigid plane would drive the bow down further for each mph increase in speed. If you have a 50lb spring then a the lift they can provide is 50lb after that they are pushed aside.