Zipwake

[Froggy]

I haven't been on here for a bit, but thought I'd post about my new Zipwake interceptors. My boat is a 1993 28 TE. She came with auto-leveling Bennett trim tabs. The auto-leveling feature long since died due to corrosion/ salt water incursion on the leveler unit. While the manual adjustment worked, it was pretty cumbersome. Last winter I ripped out the Bennett system and installed Zipwake interceptors. Like all things "boat" this took a bit longer (understatement) than the few hours that Zipwake says. That being said, the installation was pretty straightforward. I had a bit of fear that I was on the "bleeding edge" of technology but the folks at IMTRA (distributor) and Zipwake gave me excellent support.

With a summer's experience under my belt, I have to say that Zipwake is a fabulous product. The concept is somewhat counter-intuitive, unlike a trim tab system, interceptors are vertically moving bars that drop straight down from the transom into the flow of the water under the hull. They have a similar effect as a trim tab but because they operate via servo motors and don't move very far vertically, they respond instantly. They are driven by a sophisticated, yet easy to use, GPS driven control panel. I've found they work wonderfully. A great product that is worth considering for your winter list.

[amber jj]

I read a promo article on the Zipwake this summer and it got the cogs turning.At the start of the season I was having trouble with our Lenco tabs and was thinking if I had to replace them it would be with the Zipwake product if they would fit properly.
I don’t understand what the GPS has to do with the tab control.Froggy could you please explain?Thanks Bob

[Froggy]

Hi Bob,

The control head senses pitch and roll ( I assume with accelerometers) . It also uses GPS to sense speed.The reason for this is that there is a speed curve that is calculated. For any given speed there is an amount the extractors are exposed. For example, at slow speeds you want more exposure so as to push the bow down more (say 80% exposed) . At higher speeds, the extractors are retracted (mine seems to run at about 18% exposed) as you don't need so much bow down. At rest, the extractors are full retracted. The curve is based on boat size and type and, supposedly, adjusts dynamically with use to optimize speed (by minimizing need for extractor exposure). All can be overridden easily from the helm station for different loads, etc. The unit ha integral GPS but also is hooked into the NEMA 2000 backbone on my boat and uses the best available GPS signal.

arl

[amber jj]

High tech stuff.As long as it works is all that matters.Thanks for taking the time to explain. Bob

[Sisu22]

Thanks for posting. Never seen the product advertised out there. What kind of performance improvement have you realized?

[Froggy]

Zipwake says that there is something on the order of 2% efficiency improvement. That claim falls into the interesting, but hard to verify, category. However, there clearly is a reduction in surface drag as, by removing trim tabs, you reduce the wetted surface by whatever the trim tabs are of the entire wetted surface. The real improvement from my perspective is that because they are actuated by servo motors there is pretty immediate response as you change speed or have a change in load balance. Also, the dashboard screen shows their actuation in real time.

[DougSea]

I've been noticing these on boats around the yard. Prompted by this post I did some reading and I have to say, they look interesting. One poster (I forget where) talked about the difference they made on a 35 Cabo that got squirrely at high speeds. I have the same issue.

What I haven't found yet is any info on retrofitting them to a boat with recessed tabs. That could make a "not cheap" project into an expensive one, depending on how you have to deal with the pockets.

[Froggy]

Yup, you're right. The cost of filling in the recessed tab pockets would add to the cost of a Zipwake installation. While, the Zipwake would be more responsive than conventional trim tabs (due to the servo motor actuation), there would be little efficiency gain as the wetted surface would be pretty much the same before and after the ZIpwake installation (due to filling in the trim tab pockets).