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PostPosted: Mon Jul 09, 2018 2:15 pm 
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Location: Kailua, Oahu
I was out on my H16 yesterday after having done a significant overhaul.
It was 15-18 Knot winds and I was expecting the boat to have a bit more power than I was experiencing. It just seemed like something was wrong.
I raked the mast back a bit and that helped, but still felt like I needed to make an adjustment to really get the thing to work right. Last time I had the mast raked much further I had a real hard time with weather helm.

What could have been wrong?

I'm expecting the answer to be mast rake, so how does everyone set up their mast rake?

Thanks for any help you can give.

Danny


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PostPosted: Tue Jul 10, 2018 7:55 am 
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Masts are raked aft so that the main sail can be sheeted hard to where the boom blocks are close or just touch when fully sheeted. Too far aft and you can't sheet.

Main traveler position... centered for power... traveled down for reducing.

Jib clew touches the car. Adjust the blocks up or down to change the shape of the leech to match the main shape. Higher on the plate pulls the leech tight and can close the slot... pinch off the air flow. lower in the adjuster plate and it open the slot... loosens the leech. You have to sheet the main then get on the lee side to view.

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PostPosted: Tue Jul 10, 2018 10:47 am 
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Improperly adjusted rudders? Too much/ little toe?

How was the helm? you can compensate for mast rake by adjusting the rudders rearward until you have just a little weather helm.

Poorly adjusted rudders create unnecessary drag.

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PostPosted: Tue Jul 10, 2018 11:17 am 
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Quote:
you can compensate for mast rake by adjusting the rudders rearward


Rudders rake forward to neutralize weather helm. Would require drilling new holes on older boats.

Rudder and rake FAQ: https://www.hobie.com/forums/viewtopic.php?f=18&t=467

Be sure they actually are locking down and staying as far into the castings as possible too.

Another thought is a change in the wind direction. If you are used to a specific sailing direction in your area and the wind is different... that can throw you off too.

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PostPosted: Tue Jul 10, 2018 1:53 pm 
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Quote:
you can compensate for mast rake by adjusting the rudders rearward


Quote:
Rudders rake forward to neutralize weather helm.


A balanced boat has the clr and ce on the same vertical axis.
Lee helm has the clr aft of the ce, and weather helm has the clr forward of the ce.
If raking the mast aft moves the ce aft, (effectively moving the clr forward, creating more weather helm) then shouldn't adjusting the rudder rake aft effectively move the clr aft to compensate and reduce weather helm?

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PostPosted: Tue Jul 10, 2018 3:23 pm 
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It's a balance of the rudder on the pin. Aft of the axis loads the tiller. Forward goes neutral to lee helm as you move the rudder tip forward.

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PostPosted: Tue Jul 10, 2018 4:23 pm 
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mmiller wrote:
It's a balance of the rudder on the pin. Aft of the axis loads the tiller. Forward goes neutral to lee helm as you move the rudder tip forward.


Ahh... So basically the rudder pin becomes a clr and the rudder itself a ce, which is a far more concentrated effort than the boat's balance of forces.

It sounds like this could work to mask a really bad sail trim resulting in significant unnecessary drag, no? Could this be exposed by trimming the sails, raising both rudders, while accounting for X amount of degrees the lateral resistance provided from them, ie: trim the sails so a "rudderless" boat sails X degrees per sec windward/ leeward, then trim the rudders?

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PostPosted: Tue Jul 10, 2018 4:58 pm 
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The Hobie 16 uses the rudder as major lateral resistance. No daggers... just the asymmetrical hulls.

I guess it could "mask" an unbalanced rig, but it is definitely faster around the course when rig is raked full aft.

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PostPosted: Sun Jul 15, 2018 5:39 am 
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First things first….was the rudder assembly removed during your overhaul? If so, make sure it was put back on correctly. If the fore end of tillers are not slanted inward, you will have extreme toe out on the rudders. It's not an uncommon mistake.

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PostPosted: Sun Jul 15, 2018 6:42 am 
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seems like this poor guys post got hijacked!

I would check the rudder alignment before anything else.
Kiss
Then look for any other obvious things.

Your hulls are empty and dry right? I know you said a major overhaul, does that mean fiberglass repair? I had a hull that recently developed a small leak and I might not have noticed it for a while except I am obsessive about draining my boats after a trip to check hull integrity.

Was the wind switching a lot? I recently was out in 10+ winds and I too thought I should have been going faster than I was. In my case the wind was switching a lot so when I would get dialed in on a particular tack the wind was shifting a lot. A few times I nearly stopped from a gust coming at a new direction.

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PostPosted: Sun Jul 15, 2018 8:06 am 
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A1cnc wrote:
seems like this poor guys post got hijacked!



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