Query regarding old style jib tension

share hints, tips and experiences
Post Reply
Garry R

Query regarding old style jib tension

Post by Garry R » Wed Nov 12, 2008 5:46 pm

Many bits of advice concerning the old style jib tensioners where the jib is hauled up its own halyard and and hanked to the forestay say that this is done so that the forestay provides support to the jib luff and prevents sideways movement when beating to windward. However even if the forestay is relatively tight when "at rest" ie no rigging, once you pull up the jib and tension it, the forestay slackens to the point where it would flop about if the jib was not hanked to it. So I guess I am asking what is the point of hanking in the first place if there is all this untensioned forestay providing no support. In fact it seems to me that the jib luff stops the foresay flopping around than vice versa!!

Rupert
Posts: 6254
Joined: Thu Sep 16, 2004 8:40 pm
Location: Cotswold Water Park

Re: Query regarding old style jib tension

Post by Rupert » Wed Nov 12, 2008 6:48 pm

It is to stop the forestay flopping around. There is nothing more annoying than trying to read what the jib is telling you up a beat, only to have a piece of wire going slap slap slap up against it...
Rupert

Garry R

Re: Query regarding old style jib tension

Post by Garry R » Wed Nov 12, 2008 7:51 pm

but folk do cite the sideways movement of the jib as the reason.........

Rupert
Posts: 6254
Joined: Thu Sep 16, 2004 8:40 pm
Location: Cotswold Water Park

Re: Query regarding old style jib tension

Post by Rupert » Wed Nov 12, 2008 8:03 pm

For Fireflies? In the good old days, when men were men and sheep were worried, jib halyards were often made of 3 strand rope that stretched like the thing the sheep was worried about, and just cleated round an old bit of wood. If you hanked it to a taut forestay, it helped the problem. These days, (ie the last 50 years) with muscle boxes and wire halyards, jib halyard sag isn't so much of a problem, hence some classes don't even bother with them any more.
Rupert

User avatar
Ancient Geek
Posts: 1133
Joined: Wed Sep 10, 2008 9:50 am
Location: Sletten,3250, Denmark and Hampshire GU33 7LR UK

Re: Query regarding old style jib tension

Post by Ancient Geek » Wed Nov 12, 2008 8:13 pm

John Faulkner & David Tucker (also my MR Crew.) and i think David Bacon & Brian Heron had sort of lever thingy with shock cord that took the slack out of the jib haliyard down wind, we had the same thing on MR 1523 during the slack rigging enthusiasms Stars have something similat today and they are the untimate slack rigging, adjust everything as you go boat.
Simples.

Ian Malcolm
Posts: 51
Joined: Mon Mar 07, 2005 3:42 am
Location: United Kingdom

Re: Query regarding old style jib tension

Post by Ian Malcolm » Thu Nov 13, 2008 12:47 am

My albacore has a hank on jib with the fall of the halyard led down parallel to the forestay and through a block on the stemhead fitting, back accross the foredeck and then through the deck to its cleat. I understand that *OLD* Farey marine boats had more or less the same setup, but those with bow bags rather than tanks led the fall through a hole in the stemhead fitting and back under the deck.

There is a pivoting triangular plate at the top of the forestay that carries the sheeve for the halyard and as you tension the halyard, the forestay also gets tensioned.

Only problem with this setup is you have to be able to splice wire to rope to maintain it as your chances of finding someone to do so for you with 2.5mm wire and 4mm rope are negligable.
Ian Malcolm. London, ENGLAND. (FORUM REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & >32K emails --> NUL:
'Stingo' Albacore #1554 - 15' Early 60's, Uffa Fox designed,
All varnished hot moulded wooden racing dinghy.

Garry R

Re: Query regarding old style jib tension

Post by Garry R » Thu Nov 13, 2008 9:52 am

Jimmy Green Marine can do it but it costs. I got it done by Atlantic Rigging http://www.atlanticrigging.co.uk/ and they did a nice job. Once completed I thought that the rope at the splice was being worn and was worried that some wire ends would stick out as it pulled through the hanks (it is thicker at the splice) so I got some electrical cable clear shrinkwrap off ebay of the correct diameter (dirt cheap) and slid it over the splice and applied the heat gun gently. Now it slides through no problem.

ACB
Posts: 223
Joined: Sun Aug 10, 2008 12:45 am
Location: Woodbridge, Suffolk

Re: Query regarding old style jib tension

Post by ACB » Fri Nov 14, 2008 3:51 pm

Ian's description is spot on.

The early racing dinghies were rigged like "little big boats", right down to the burgee halyards. The Firefly is a beautiful example.

F 3163 "Aquarius",
IC K229 nameless for the time being
I14 K377 "Mercury" - long term rebuild project

Michael Brigg
Posts: 1663
Joined: Fri Jul 06, 2007 7:11 pm
Location: Gosport, UK

Re: Query regarding old style jib tension

Post by Michael Brigg » Fri Nov 14, 2008 8:29 pm

Malcolm said:-
There is a pivoting triangular plate at the top of the forestay that carries the sheeve for the halyard and as you tension the halyard, the forestay also gets tensioned.
We discussed some of this at some length recently on Catriona's "My new old firefly" thead and looking at the shape of the triangular block I'm not convinced that the fulcrum between the two attachments is angled sufficiently to gie a self-tensioning effect which at most would give perhaps 5mm of movement.

Here is a photo of my old reynolds jib/forestay arrangement (before it went over the side of the my boat.)

http://s225.photobucket.com/albums/dd31 ... 008008.jpg

. (If you want to look around the album theres a range of other photos which would make a christmas quiz along the lines of What happenend to this one?!)



With regard to the wire halyard and rope tail , I personally found that the splice was so liable to jam in the blocks and hanks as to be a total hazard. The main purpose of the rope tail is to facilitate the re theading of the damn thing if it ever gets lose and escapes through the hole at the front, as the lower end of the wire becomes so kinked after being wound around the cleats under the deck as to be impossible to re thread whereas this is a relatively simple matter using a rope tail and the hook end of a jib stick.

The rope tail is also less likely to unwind itself after making it up around the underdeck cleat once the sail is hoisted and the spare wire wrap-coiled around the two cleats. (Start at the back then the front and round again until all tidied away. The wire between the bow fairlead and stern cleat can now be pulled sideways onto the rack for tension.
Michael Brigg

Post Reply