Topic : Transom Yoke

I am thinking of doing away with the hoop and replacing it with the mainsheet led back along the boom to a transom yoke. This would make the boat more open plan, increasing mobility, but still enabling you to centralise the boom without applying leech tension. 

The main and only objection seems to be the requirement for a shorter tiller extension. Has anyone tried this, and experimented with over lengh booms, so that the yoke take off can be taken back to the transom? Or played with the lenghts off tiller extension and tiller bar to achieve the best compromise? And if you did do it, how much shorter does the extension need to be?

Posted: 13/02/2009 16:15:17
By: John O
Is this what you had in mind?

Posted: 13/02/2009 16:47:29
By: Garry R
Yes - however you splice the tails into the mainshett so that they "suck" into the aft block, then boom is dead centre

Posted: 13/02/2009 16:53:37
By: John O
Why not just use the strop in the centre of the boat? I think some boats do.

Posted: 13/02/2009 18:25:16
By: .
This system is used by Scorpions. Possibly because they're narrower so the short extension isn't an issue. 

The 12's use a "double strop" where the spliced yooke is pulled up into the block at the end of the boom and the sheet goes dowm through a ratchet on the second yoke to hand - some pics on their site if anyone interested.

Having seen some reference somewhere to Transom sheeting being preferable when a hull is too old to take high rig tensions, I was considering taking 2349 back to this system?

or am I missing something?

Posted: 13/02/2009 20:26:37
By: Giles
because with strops you need to shorten the windward strop to bring the take off point up to windward, which must bring the takeoff point lower, so to centralise the boom you have to add tension to the leech, which is one of the things you are trying to avoid with the track mounted on a hoop. So it can be used, but adds more moving parts and does not do the job as well as a hoop.

Posted: 13/02/2009 20:37:23
By: john o
but it works on fireballs, 5o5's, Ospreys, Graduates, etc etc etc etc etc begs the question , why the hoop??? Just think of the weight saving!!!!!!!!!!

Posted: 13/02/2009 20:52:03
By: Yoke boy
What age boat are we talking abour?

Posted: 13/02/2009 21:02:50
By: Chris M
Thanks for replies, the system undoubtably works on other classes, however the questions really are, why is it not used on Merlins? Is it only because you need a shorter tiller extension? And how much shorter if you lenghen the boom?

The weight saving is only an advantage if you are currently over weight as the scaffold weight will be replaced by lead in the same place. The age of the boat does not matter if the boat currently has a centre main as the loadings on the Main sheet jammer block is the same. (less purchases are made up by the increase in leverage obtained by sheet on the boom end)

Posted: 14/02/2009 13:13:07
By: John O
Replacing the hoop with strops in the centre of the boat, anchored on the thwart about a foot either side of the centre-line works well with an older type of boat provided the strops are long enough to reach (just) the lower block on the boom when close hauled. If they are too short (or too long) the boom sags off too far to leeward. The improvements, apart from saving weight, are that strops made from Vectran (I think) that doesn't stretch and eye splices by threading through itself can be adjusted to suit mast pre-bend each time the boat is rigged and they don't clutter up the middle of the cockpit. The downside is that an oldie like me loses his zimmer frame!

Posted: 14/02/2009 17:07:50
By: Peter 3112
I have been using the system you discribed on my merlins for 15 years, it does work very well, the only problem is, the laser style tiller tacking made you do a handbreak turn at every tack, (traing day video showed this up) so i went to a twin strop transom sheeting for the last 2 years and found it to be the best solution of all the systems.
have fun.
Dave F

Posted: 16/02/2009 11:57:25
By: DaveF
Found a pic
Look at how much room there is in the centre of the boat, in light winds i could tack infront of the thwat.
Having a nimble small crew helps! (holding the main sheet)
Dave F

Posted: 16/02/2009 12:03:32
By: DaveF
See Peter 3112 post, what are and how do "eye splices" work. I have a strop secured through the thwart with a figure of 8 stopper knot om the underside. This is a pain to undo when trying to adjust the strop for rake

Posted: 16/02/2009 13:19:26
By: Jon
My recollection of sailing 12s (though years back)was that as the boats got wider the tiller extension became more of a problem. Initially I could just "hop" the extension over the mainsheet (timing was critical) but with wider boats I had to change so the tiller extension came round in front of the flexible joint (crews beware!)

With the width of the merlin i think a short tiller extension would not work, but the technique I used should work if you get the tiller length right (not too long)

Posted: 16/02/2009 16:03:08
By: Andy M
I used about 1 metre of 8 mm Vectran that will thread back through itself. I made the centre eye by threading the ends through the rope and back 5 times over a length of 10 cm and the ends are made into soft eyes which loop round the eyes of stainless steel flat plates bolted through the thwart. The variable length 'eye splices' are made by threading the vectran back through itself for approx 15 cm using a bodkin made from an ally coat hanger. You should leave approx 20 cm spare for the adjustment which can be locked to length with a figure of 8 knot.

Posted: 18/02/2009 18:35:09
By: Peter 3112


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