Took our new 20 out yesterday and was curious about a couple things...
Downhaul. Is it as important on these Dacron sails and mast as on the present day boats? Our F16 has the pentex sails and prebend in the mast and the downhaul really shapes the sail.
Daggerboards. When the wind starts picking up is it recommended to raise them when heading upwind?
Downhaul and board positions
-
havliii
- Professional
- Posts: 272
- Joined: March 27th, 2011, 8:12 pm
- Boat Make/Model: SuperCat 19, Modded SC20
- Location: Fredericksburg Virginia
Re: Downhaul and board positions
Mac, I use a six to one downhaul and yes it is important to downhaul the bejezus out of the dacron main.
The answer about the boards is a bit tougher question, on my boat I can completely balance out the helm, on any point of sail, by how much board I use. Example, if I use full boards on a beam reach it actually creates 'lee helm' in the tiller, which I definitely don't want, so the boards come up. Upwind I point much higher and have perfect fingertip helm control with 3/4 to full board down at most any windspeed. When it's really crankin' (as I posted earlier) I furl the jib upwind, this creates a totally different balance on the helm so then I have to move the boards up, to achieve the balance that I want, and then it varies from one quarter to one half board.
Basically I use the 'feel' of the flow over the rudders to determine how much board is needed. If the rudders are balanced and flowing smoothly, (I am guessing here) it represents a very low drag condition, the upside of this 'balancing out' is that the '20' then becomes a docile sweet sailing machine instead of a wild beast.
The answer about the boards is a bit tougher question, on my boat I can completely balance out the helm, on any point of sail, by how much board I use. Example, if I use full boards on a beam reach it actually creates 'lee helm' in the tiller, which I definitely don't want, so the boards come up. Upwind I point much higher and have perfect fingertip helm control with 3/4 to full board down at most any windspeed. When it's really crankin' (as I posted earlier) I furl the jib upwind, this creates a totally different balance on the helm so then I have to move the boards up, to achieve the balance that I want, and then it varies from one quarter to one half board.
Basically I use the 'feel' of the flow over the rudders to determine how much board is needed. If the rudders are balanced and flowing smoothly, (I am guessing here) it represents a very low drag condition, the upside of this 'balancing out' is that the '20' then becomes a docile sweet sailing machine instead of a wild beast.
-
jjd78
- Professional
- Posts: 85
- Joined: January 29th, 2006, 5:09 pm
- Boat Make/Model: SC17, 1-SC15, 3-SC17 and SC19
- Location: CHESAPEAKE, VA
Re: Downhaul and board positions
Mac,
When I used to have the SC19 in bigger wind I'd pull up the boards some so the boat would drift a little sideways.. This way I could drive a little deeper
When I used to have the SC19 in bigger wind I'd pull up the boards some so the boat would drift a little sideways.. This way I could drive a little deeper
-
Mac M
- Professional
- Posts: 232
- Joined: June 13th, 2012, 5:05 am
- Boat Make/Model: SC17
- Location: Lugoff, SC
Re: Downhaul and board positions
No need to worry about breaking a board going upwind or,reaching in bigger air? Those things are big, long, and expensive to replace!
-
DanBerger
- Professional
- Posts: 280
- Joined: May 3rd, 2004, 3:29 pm
- Boat Make/Model: SC 15 w/ spin!, SC 19
- Location: Norfolk, VA
Re: Downhaul and board positions
easy, there big guy--comparing your Supercat 20 to 'modern day boats' is just kicking the hornets nest. You're going to upset somebody!
On the downhaul, it is really important on any boat. I can adjust mine from the wire on my 15 and feel the boat pick up in speed. The way the sails are cut makes a difference in the mast bend when you tighten the downhaul. You should be able to see it when you are just sitting there.
Now, the 20 should hae spreaders that give the mast some pre-bend. That in itself should shape the sail some and tightening the downhaul just makes the sail shape better as it conforms to the shape or bend of the mast.
I know where you can get an adjustable 6:1 downhaul just like mine
I could be off on that description, but that is how it appears to me.
On the daggers, you should have them all the way up when going downwind. I didn't get much time in on my 20, but on my A cat, I leave them all the way down going upwind in medium to high wind. If the wind is very light, I'll bring them up about half way to cut down on drag. That is both with curved and straight boards.
I have installed curved boards in my boat and it acts completely diffeerent than the straight boards. Downwind, we are supposed to keep the boards down for lift, but that's only if you have wind. In the light stuff, I have the boards all the way up. I would never leave the straight boards down when going downwind.
On the downhaul, it is really important on any boat. I can adjust mine from the wire on my 15 and feel the boat pick up in speed. The way the sails are cut makes a difference in the mast bend when you tighten the downhaul. You should be able to see it when you are just sitting there.
Now, the 20 should hae spreaders that give the mast some pre-bend. That in itself should shape the sail some and tightening the downhaul just makes the sail shape better as it conforms to the shape or bend of the mast.
I know where you can get an adjustable 6:1 downhaul just like mine
I could be off on that description, but that is how it appears to me.
On the daggers, you should have them all the way up when going downwind. I didn't get much time in on my 20, but on my A cat, I leave them all the way down going upwind in medium to high wind. If the wind is very light, I'll bring them up about half way to cut down on drag. That is both with curved and straight boards.
I have installed curved boards in my boat and it acts completely diffeerent than the straight boards. Downwind, we are supposed to keep the boards down for lift, but that's only if you have wind. In the light stuff, I have the boards all the way up. I would never leave the straight boards down when going downwind.
-
Mac M
- Professional
- Posts: 232
- Joined: June 13th, 2012, 5:05 am
- Boat Make/Model: SC17
- Location: Lugoff, SC
Re: Downhaul and board positions
Not trying to kick any nests for sure! I cant sail the boat to its potential so it really doesnt matter when ot was built haha. I was under the assumption that these were NOT masts with Prebend, hence the present day comment. I asked Tom about diamond wire tension on my '89 XL (same mast) and he said that wasn't a prebend mast and didn't even have the right spreader arm tips. It looks as if ill get the first sail with some wind this weekend so ill see what's up. Will put my go pro on board and report back with some video!
Im aware of the boards up going downwind. I've just seen some Supercat videos with people sailing what appears to be upwind with the boards in various up positions. Guess I'm need to listen to my friend Nigel and 'quit watching videos' haha.
Im aware of the boards up going downwind. I've just seen some Supercat videos with people sailing what appears to be upwind with the boards in various up positions. Guess I'm need to listen to my friend Nigel and 'quit watching videos' haha.
-
Kevin Keller
- Professional
- Posts: 362
- Joined: September 24th, 2006, 2:56 am
- Boat Make/Model: SC-20, ARC22
- Location: Honolulu
Re: Downhaul and board positions
Tom told me once that the SC20 mast does not have a prebend, at least the older ones.
The only time I leave my boards up going upwind is when I might hit something. Otherwise I usually keep them about 6" sticking up unless I am racing. I have hit something hard before in deep water, might have been a turtle not sure.
My two cents.
Kevin
The only time I leave my boards up going upwind is when I might hit something. Otherwise I usually keep them about 6" sticking up unless I am racing. I have hit something hard before in deep water, might have been a turtle not sure.
My two cents.
Kevin