sterenn
regular
Reged: 15/03/2007
Posts: 194
Loc: Paris France
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Bonjour
I confirm that the "Atoms" is a good stuff that was very popular in France. You may find bit and parts on dedicated websites as "Sail the World" (STW is a french web site!!!). I could support you on the langage.
The main issue about the trim tab is the respond delay: the wind vane turns the trim that turns the rudder...
You have the same issue with the classical "Wind vane" the wind vane turns the watervane that rotates and turns the rudder.
The respond delay is an important issue on sensitive boat (as a figarOne or a mini). A wind vane would lead to a "drunken dolphin route".
With a steady boat with high heading stability (long keel for example) the boat will smooth the swinging and it will be OK.
The main interest of the trim-tab is that there are almost no working efforts on the mecanical parts. The required resistance is linked to the breaking on board waves splashing efforts.
An ATOMS wind vane connected to a tim tab would be overdimensionned, wich is not unpleasant.
An important issue is the hydrodynamic profile of the trim tab.
Very often the trims are only flat ironsheets. They need a big angle (between 5° and 10°) to start to create a lift. With an adapted profile with a big lift to angle ratio at small angles the systems would work much better and would become much more sensible. The trim profile should be in "clear" water behind (1 or 2 inches) the trealing edge vortex of the rudder.
But, it takes more time and money to choose and build a profile than to cut a stainless-steel sheet......
An alternative would be to prepare a trim system as a back up.
Eric
STW for sale
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Pourquoi faire simple quand on peut faire complique ?
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sterenn
regular
Reged: 15/03/2007
Posts: 194
Loc: Paris France
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Bonjour
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it (The NAVIK) has it short comings, and build quality and spares availability/cost was a main bug-bear
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I completly agree. It's a twenty years old concept with no improvement since.
The only point I would add is that, as the mecanical efforts are very small and as the waterwane (the only part supporting effort) is moving only on an horizontal axis it is relatively easy to repear it on board with bits and parts. A french navigator turned round the world on a 9m boat and almost rebuilt his Navik along his trip.
Eric
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Pourquoi faire simple quand on peut faire complique ?
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John_E
regular
Reged: 15/05/2006
Posts: 155
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I am waiting for a SeaFeather to be delivered in the next few weeks (They are built to order). After much searching and worries about weight (it's going on a Vic 26) I checked out a couple of SeaFeather installations at my local marina and was very impressed by what I found so called Paul (a very nice man), dropped him some measurements and a couple of photos and the rig is in build even as I tripe. Will let you know how it goes when it arrives.
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June too soon, July stand by, August it must, September? I can never remember... But I bet it's gonna be nasty 
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edgiee
new user
Reged: 06/12/2007
Posts: 6
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Anyone used or using a Hasler SP gear ?
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