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Old 22-01-2013, 04:12   #16
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Re: Excessive Rake

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Originally Posted by Cheechako View Post
Looks pretty excessive to me. Maybe he has a lee helm problem! Or maybe he thinks he's a pirate!
Nah, if that were an 'adjustment' for lee helm, the boom would be scraping the cockpit floor, and every sail he owns would have had to be recut. The fact that we're seeing the same amount of rake on different Dean boats means that it's safe to assume the rake is by design.
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Old 22-01-2013, 08:54   #17
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Re: Excessive Rake

I always assumed it was just a design compromise to get the mast off the cabin top while maintaining balance. I woder if a side benefit could be that it relieves some batten compression making it easier to raise and lower the main without expensive battcars and tracks?
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Old 22-01-2013, 09:13   #18
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Re: Excessive Rake

None of them have the sails up so it doesn't matter when all they do is motor but it looks like they're going faster that way.
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Old 22-01-2013, 09:21   #19
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Re: Excessive Rake

There's one for sale in Ft. Myers Beach, Fl. mooring field. I just thought the owner had raked the mast back for some unknown to me reason, but now I know
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Old 22-01-2013, 10:15   #20
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Re: Excessive Rake

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Originally Posted by cal40john View Post
I would argue that it is a lack of buoyancy in the bows that allow a cat to pitch bow down more than a keelboat. More an issue on beach cats than cruising cats. And while the CE is moving forward as you pitch bow down, at least on all the beach cats I have sailed the CLR moves forward much faster and farther due to more bow in the water and less stern in resulting in weather helm, not lee helm.

Top racing beach cat sailors change rake for the conditions. Hobie 16s with no daggerboard have a different reason. Boats with daggerboards will sail with a more upright mast in lighter conditions and will rake back for stronger winds. I haven't seen an explanation that I like yet but talk to any racing sailor and they will tell you that raking the mast aft will depower the rig and allow you to point higher, this is for cats, planing dinghies and keelboats. The beach cat sailors also like to point out that the weight of mast is further aft, but that seems a minor point to me.

The first cat I chartered, a Privilege 39 had a lot of rake, it did not look like other Privilege 39s. On one day we had a nice wind and on a broad reach we had to reef the main because the weather helm was so bad the steering system was binding and locking up. At first I thought we had the rudder hard over, but a lull unloaded the gear and then I could turn it farther.

I like the other explanation better that it was designed with the mast base forward and the mast raked to balance the boat.

JOhn
One reason that I hinted at is that non-board beach cats can gain lift from their deep rudders IF the CE is further back AND they keep the boat moving fast enough to prevent too much weather helm. In effect, they use the rudders as boards and point higher. It also helps keep the lee bow up, and moving weight back also helps, though that is a small item. Thus, this is a heavy air up wind and tight reaching tuning and is COMPLETELY irrelevant to this boat.
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Old 22-01-2013, 10:31   #21
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Re: Excessive Rake

Somehow it looks far better on a sharpie.....
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Old 22-01-2013, 10:40   #22
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Re: Excessive Rake

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Originally Posted by thinwater View Post
One reason that I hinted at is that non-board beach cats can gain lift from their deep rudders IF the CE is further back AND they keep the boat moving fast enough to prevent too much weather helm. In effect, they use the rudders as boards and point higher. It also helps keep the lee bow up, and moving weight back also helps, though that is a small item. Thus, this is a heavy air up wind and tight reaching tuning and is COMPLETELY irrelevant to this boat.
Yes you're correct that they rake the mast aft to to gain lift, but the way that happens is you are creating weather helm so the rudder has to be angled to steer a straight line. This creates an angle of attack on the rudder so it provides lift to weather. The weather helm is there regardless of speed and the force on the helm increases with speed. This is why Hobie 16 racers spend a fair amount of time adjusting their rudder rake. You rake it forward which actually minimally increases weather helm but puts some of the blade area in front of the pintle axis balancing the forces felt on the tiller. The weather helm is still there, the boat still wants to round up and the rudder is at an angle.

Our club had some older Hobie 16s that had the old rudder head that did not allow rudder rake adjustment. Well you could, you fill the bolt holes in the rudder and drill new ones where you want them. Anyway some people started racing these boats and raked the mast to be more competitive without modding the rudder. After awhile my arm would get so tired from the helm that I had to give the mainsheet to the crew and hold the hiking stick with both hands.

(If you get it wrong and put too much area in front of the pintle axis you get positive feedback and the rudder wants to slam hard over. Makes for a very interesting steering experience and another trip to refilling the bolt holes with epoxy.)

Tiller tug versus weather helm:

On the Wire - Feature
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Old 22-01-2013, 14:34   #23
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Re: Excessive Rake

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None of them have the sails up so it doesn't matter when all they do is motor but it looks like they're going faster that way.
3 photo's - one anchored, one in a marina and one in glassed-out conditions. No surprise they're not sailing.
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Old 22-01-2013, 14:55   #24
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Re: Excessive Rake

Its not the only ridiculous thing about a dean cat - they have no tramp either with the space filled with berths- so maybe the 2 are related ie too much weight forard so rake the hell out of the mast to push the CE aft and stop the bow digging into the next greenback....
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Old 22-01-2013, 15:23   #25
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Re: Excessive Rake

Sorry ... what is "Tramp"?
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Old 22-01-2013, 16:12   #26
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Re: Excessive Rake

tramp = trampoline at the front of (most) cats to keep forard weight down and allow large seas through
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Old 22-01-2013, 16:27   #27
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Re: Excessive Rake

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tramp = trampoline at the front of (most) cats to keep forard weight down and allow large seas through
Nah, it's those pretty ladies my Admiral won't allow me to take sailing
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Old 22-01-2013, 16:46   #28
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Re: Excessive Rake

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Originally Posted by cal40john View Post
Yes you're correct that they rake the mast aft to to gain lift, but the way that happens is you are creating weather helm so the rudder has to be angled to steer a straight line. This creates an angle of attack on the rudder so it provides lift to weather. The weather helm is there regardless of speed and the force on the helm increases with speed. This is why Hobie 16 racers spend a fair amount of time adjusting their rudder rake. You rake it forward which actually minimally increases weather helm but puts some of the blade area in front of the pintle axis balancing the forces felt on the tiller. The weather helm is still there, the boat still wants to round up and the rudder is at an angle.

Our club had some older Hobie 16s that had the old rudder head that did not allow rudder rake adjustment. Well you could, you fill the bolt holes in the rudder and drill new ones where you want them. Anyway some people started racing these boats and raked the mast to be more competitive without modding the rudder. After awhile my arm would get so tired from the helm that I had to give the mainsheet to the crew and hold the hiking stick with both hands.

(If you get it wrong and put too much area in front of the pintle axis you get positive feedback and the rudder wants to slam hard over. Makes for a very interesting steering experience and another trip to refilling the bolt holes with epoxy.)

Tiller tug versus weather helm:

On the Wire - Feature
Yeah, what he said.

I had 2 boats that favored load on the rudder: Prindle 16 and Stiletto 27. Both had very deep high aspect rudders. And both had adjustable rudder rake. Of course, you had to watch your main trim to avoid excessive helm angle. For those boats, it worked. For my current boat (cruising cat) no way.
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Old 22-01-2013, 17:35   #29
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Re: Excessive Rake

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Nah, it's those pretty ladies my Admiral won't allow me to take sailing
Hmmm another reason to hate the Deans now!

and dare i say it the Geminis........
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Old 23-01-2013, 06:24   #30
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Re: Excessive Rake

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...
Could it have been to get the mast base out of the salon? Not a good enough reason.

Hmm....
Only reason I can think of on a cruising cat. I don't know of any other cruising cat (or performance boat for that matter) with such an extreme rake.
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