Topic : Strops

This old chestnut again as I am still a bit confused!

I see on a lot of old boats, including one or two new boats, the strop is fixed to the transom and not the thwart. Is there a reason for this?

I have had some very good advice in the past on the same subject as to the pros and cons but wanted to spread the net in respect of more opinion, some say transom and some say thwart. With the advent of mainsheet jammers why would you want to sheet a main from behind when you can do it looking forward?

If a boat is deck stepped does this make a difference (as is my boat 908)? Any responses/advice greatly appreciated.

Thanks in advance.


Posted: 24/02/2010 20:46:16
By: Richard Battey
On older booms with a bit of bend in them, perhaps you would have got more leach tension with strop across the transom?

Posted: 24/02/2010 21:14:31
By: :)
HI Richard,

The N12's have had a thing about strops on the transom for a while (one of the club members swears by it).

I think the argument runs that you can get the boom on the centreline (fairly easily) and have leech tension.
Compared to the current square top arrangement which should achieve the same thing (track takes the block to windward, boom is on the centreline) but is heavier and more complicated mechanically.
OTOH, centre mainsheet doesn't put on as much leech tension which allows a little more give in the rig for gust management...


Posted: 24/02/2010 21:32:16
By: Colin
To do with leech tension and getting the boom on the centreline.  With a strop however well-engineered the block on the boom will be sagging off a bit to leeward.  If you do that half way down the boom the effect is worse than at the end.  The strop systems on Merlins then run the sheet down (even in) the boom to a centre jammer on the more modern boats, the only reason for keeping the sheet itself at the transom is that it gets in the way in a narrow boat.  Also if you have a strop at the end of the boom you do not need a purchase on the main, if you have it in the middle you do.  Think that's it.

Posted: 25/02/2010 12:27:52
By: Andrew M
I have an adjustable strop on my NSM1 anchored to the thwart a foot or so either side of the centre line. With the legs as long as possible but the purchase still applying downward force there is a bit of sag but less than with a rounded hoop. The only viable solution is to have a square top hoop and enjoy the extra bits of string! Perhaps a home made carbon one as in the library section would be a good project for the warmer weather? 
The boat seems to go to windward best in open water with the jib a centimeter from tight and the main tightened right in to the strop. But it is an old fashioned rig.

Posted: 26/02/2010 18:39:12
By: Peter 3112
Transom main pros:

-Easier to centreline boom.
-More control over leech tension.
-Easier to move around boat.
-Helm keeps weight forward during tacks.

Transom main cons:

-Jibes are harder (need to get crew to pull boom over)
-Pumping less effective.
-Sheet hangs in the water, catches around transom.
-Have to tack and jibe facing backwards.

I reckon transom mains are better on narrow boats.

Posted: 26/02/2010 23:03:33
By: .Phil Dalby.
Please remove "pumping" from the list of  cons as you aren't supposed to do that as I understand the rules unless you mean pumping is a con in a different sense of the word.

Posted: 27/02/2010 15:52:13
By: Pumps are for bicycles
Well that's my little strop for the day!!

Posted: 27/02/2010 15:53:02
By: Pumps are for bicycles
Has any one ever tried a split tale main sheet?

Posted: 27/02/2010 17:03:22
By: pabs
I went from thwart strops to fireball style split-tail mainsheet in my Lark. Made a big improvement to pointing.
The big downside is jibing even with an additional hauling line or crew on the kicker, which is presumably why it has gone out of favour on Larks: Fireballs are rather more stable.
no real difference to 'adjusting to each wave' or flipping the top batten.
makes it easier for the crew to move back than with wide strops.
dragging in the water can happen but if the wind is that light, helm (or crew) is probably able to hold the boom.
I'm not sure about boat width but would certainly recommend trying a split mainsheet as a cheap easy option for getting the boom centred without too much leach tension. Particularly suitable for an old boat with a long wooden boom?
With a short boom I could see the strop getting in the way: if the fastening points on the hull are too far back relative to the length of the boom it could be possible to pull the boom off the gooseneck in light winds, not good. Also the purchase may not be high enough: some fireballs are sailed with an additional purchase but to my mind that ends up too much the other way.

Posted: 27/02/2010 20:37:43
By: ex merlin
Steve Laney used a split bridle on Carbonator (and has the same system on the new boat). Jacko has one too. Takes a considerable amount of stainless steel weight out of the boat, plus one less string to pull during a tack. The main difficulty is dealing with the tiller, Steve has s shorter one with a flexible end that can swing forward during a tack. Larks & Furballs don't have quite the same problem. You could experiment with a skiff style twin tiller extension system .... or take the sheet direct from the boom in which case the tiller extension could go forward under the sheet (if you catch my drift).

Posted: 27/02/2010 21:42:43
By: Andy Hay - 3626 Business as Usual
Split tailed mainsheets work & are used successfully in many classes so it has always puzzled me why Merlin’s have the hoop arrangements they do. It cannot be simply the length of the tiller + tiller extension because Lasers, along with other classes, have tiller +  extensions that extend forward of the center part of the mainsheet.

So just what are the advantages of the hoop over the split tailed mainsheet please?

Posted: 28/02/2010 20:11:51
By: DO
easy: something for old geezers to hold on to when they tack!

Posted: 28/02/2010 21:20:06
By: Ex merlin
"The main difficulty is dealing with the tiller" Having borrowed a Merlin some years ago with the transom strop arrangement for Salcombe week I can confirm this is a MAJOR understatement! It was a bleeding nightmare at Salcombe!  That said the owner had no problems with it and neither does Jacko these days - but to the uninitiated it was a steep steep learning curve which I never mastered.

Posted: 01/03/2010 00:00:57
By: IanL
Any other reasons?

Posted: 02/03/2010 08:43:55
By: DO


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