Headstay Length

Started by Justin Scott, June 05, 2013, 12:02:13 PM

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Duncan Adams

Hi all
Interesting reading about the head stay length, I'm really keen to find out if the mast foot on my Bennett boat (not sure of the hull number but GBR 602) is in the right place compared to the new boats. I don't have anything to measure over here in the UK so help would be really helpful.
I'd then like to figure out what the advantages/disadvantages are if my mast foot is in the wrong place?
We also race in an IRC handicap fleet, I'm looking into ways of barber hauling the jib in closer to the centreline so any ideas in this area would be good. We've tried using the lazy sheet, but its not great and for this type of racing where I'm not bound by class rules I wonder if there's a better solution?
Cheers
Duncan.

Dave Nickerson

Duncan - Here's a way to check step location from one of the sailmaker tuning guides.  It should be close and some folks might be slightly aft of this currently (1/2")

1.   Check and measure the mast step position in the boat.  Start from a point on the stern/deck intersection 7" to the side from centerline of the rudder tower.  Make a mark on the deck.  Then measure from this mark to the aft face of the mast (or to the forward side of the aft pin in the mast step if the mast isn't up).  Measurement  should be about (plus or minus ΒΌ"):
a.   Bennett t ( Mk I) & Rondar Mk II boats:   148"            
b.   Rondar Mark III (sugar-scoop transom):     146 1/4"
c.   Remember that the step fitting may not always be in the exact same place on some of the older boats.  For example, many of the Bennett boats have had repairs to their steps and the fittings can end up reinstalled in a slightly different place.

Inhauling with the windward sheet actually works well for most of us.  A general benchmark is to bring the clew in over the deck joint - until all are hiking and then back to normal sheeting.

Good luck

Dave N
Viper #208 - Noank, CT

Duncan Adams

Thanks Dave,
It could be a bit tricky for us to measure using the start point as described. We've installed the new rudder post moulding from Rondar, which over the existing transom.
Does anyone have the measurement from the front edge of the keel (when up) to the back of mast all at deck level, I assum the keel position has never changed?

Cheers.

Tim Carter

Duncan, I seem to remember something like 17-18"..  I will check.  There is some play in the keel fore and aft when it sits on the trailer.
Lt Coast Gov

Duncan Adams

Thanks Tim, I'll have at look at ours over the weekend.

Dave Nickerson

Works with old and new rudder tower.  My old boat 18 made that transition.  What's key is just measuring from the centerline off to a point 7" to the side,
Viper #208 - Noank, CT

Justin Scott

Hello Duncan,

I have had a Pre-Rondar for a number of years.
With the switch to the carbon mast, the mast butt has to be moved considerably further aft. It required removing the mast track on the floor of the deck and moving it aft. Consider putting a thin plate underneath the mast track to spread the load and reduce compression of the floor under the mast. I will measure my mast butt position when I take the cover off. For me, it was a matter of trial and error as I played with the variances of rake and mast butt. If you like sailing with a more upright mast, you can move the butt a bit further aft, and the helm will balance with less rake.  If you sail in a lot of big breeze, you could go one hole further forward from base and then add more rake to compensate.  BUT this seems to open the jib slot and it seems you want a tighter slot, not wider. My guess is that you are sailing with a lot of rake to compensate for a butt that is too far forward.

As far as jib slot is concerned. I have seen a Viper put a second inboard jib track on for handicap sailing. I don't know how that worked for them. The jib slot in OD configuration is deliberately a little on the generous side to make the boat easy to sail.
I used to Barber Haul, IMHO, the most noticeable impact is that it adds twist to the jib and worked well to okay in light/light medium days in Marblehead's Atlantic swells.  We don't barber haul any more. I think there are two reasons (I) The newer jibs seem to be cut a bit fuller and a bit more twisted up high and (2) I miss those long Marblehead rollers. Its all waves and chop for me nowadays.....Miami to Charleston to LIS .

BUT I will be at Marblehead in July for Race Week. Gawd, I love when the occasional Easterly cranks in because steering a Viper in big breeze down long Marblehead Atlantic rollers verges on the erotic!
Viper - Mambo Kings
Right Coast Refreshments Committee

Duncan Adams

Thanks Justin,
Some really interesting stuff there. We are currently using the old Ali rig for IRC racing and I've rigged up an eye on the the back of the mast that I run barber haulers from. Seems to work really well in up to 10knots, lots more height ( I'm sailing against J111's, J109, half toners and a few other IRC race boats) without hurting the speed.
We are still looking to sort the rake out though. I'm not convinced I've got it right, but I'd really like some base measurements to see where we are. By the sound of it my mast foot needs looking at, so any measurements (off the the front of the keel when lifted) would be great!

Oh one other thing, if you know anyone who's just bought a new a new kite and may have a good one kicking around I'd be really interested, put a big rip in ours yesterday!

Cheers
Duncan