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PostPosted: Sun Sep 20, 2009 2:47 pm 
Site Rank - Old Salt

Joined: Sun Aug 12, 2007 5:17 pm
Posts: 641
Location: Auckland NZ
I have been asked for photos of the rigging I have used to deploy a jib and stay the mast in another post so I thought that rather than hide them in that post I would make them into a new topic.

I haven’t yet got a photos or film of the full rig in situ (didn't have time this morning). If I have done it right photos of the components should be shown individually in the description below but a set of photos is availalable at the link below & I will get an 'action' shot ASAP:

My hull is an AI hull but the hull type should not make any difference as the approach should work on any hull. I use an adapter to allow the AI mastbase to accept the standard mast but the technique should work exactly the same way.

Here’s a photo of the adapter – made from an offcut of a broken windsurfer mast plus parts bought from Hobie & a DIY store:

When you add a jib (even a small one) the increased sail area puts considerably more pressure on the mast which, being unsupported, is even more liable to deform; this MIGHT cause the mast to break, but it WILL cause the sails, both main and jib, to lose their shape and consequently their power.

In my experience you can sail with a jib on the unsupported mast but only in very light winds and then only downwind because in anything else the mast deforms so much that either both sails lose shape badly or the sailor chickens out for fear of the mast breaking. Basically, when rigging a jib, to get more out of both sails and reduce the risk of a broken mast, you need to support the mast with backstay(s) and a forestay.

The good news is that it is not hard to do & running a jib in light winds is a great way to improve your boat’s sailing performance.

In light winds I rig a jib on my boat via a stayed mast this way:

1. I have 2 micro blocks permanently attached to the head of the sail/mast top with a bit of light line.
In the photo you can see the arrangement I have for the head of the sail. N.B. there’s no need to detach the head of the sail – this was for another experiment of mine which hasn’t yet worked out; the same rigging works on an unmodified sail. Ignore the blue lines; the grey lines attach the blocks, one on either side; the red line is the port jib-halyard/backstay; the green line is the starboard jib-halyard/backstay. The rear fall of the red & green lines is led down the appropriate side of the sail so that when the sail is unfurled they fall to hand in the right place to act as backstays. The forward fall of both the red and green lines together forms the jib halyard & attach to the head of the sail via a micro snap-shackle.

2. The forestay attaches to the head of a small jib which I haul up to the mast top to a stop in the line by hauling on both of the backstay falls. If you look carefully in the photo you can see the blue plastic ‘stopper’ which determines how high the jib can be hauled and the two lines of the jib halyard passing through it & tied to the top of the jib-head snap shackle (the red line coming up from the bottom of the sail and the green line in the jaws of the snap shackle are the ‘backstays’ in their position for sail-furling, one on either side of the sail)

4. The tack of the jb is attached to an 'outhaul' which pulls the sail out to the front of the boat; thus the luff of the jib substitutes for the normal forestay rigging (i.e. the sail is set 'flying').
The outhaul can be seen in this photo (note I have retro-fitted a padeye on the foredeck in the correct position for my jib):

Here it is with the jib attached (via a micro snap-shackle):

And here is the arrangement for the inboard end – I set the line up before I leave shore. Note the tied-on ‘cleat handle’ which is the arrangement I use to belay the end of the outhaul when under tension. You can also see what the AI mastbase adapter looks like in situ.

5. The ends of both backstays are attached to padeyes beside the cockpit - attaching the ends of the backstays in this way does not tension the forestay at all because they are too long.
Here is the arrangement I use. I have replaced the screw in cleats with the screw-in padeyes to provide the attachment point for the hooks that I use to secure the backstays (via loops in the line) and the plastic clam cleats I use as sheet ‘winches’. Luckily the AI hull has an extra knob on each side (for the Ama attachments – see photo) which I can use to secure my paddle instead of the screw-in cleat I have replaced with a padeye. The hooks are only attached with cable ties because I ran out of line.

6. When sailing on any given tack I tension the windward backstay against the forestay by pulling it in and I release the leeward backstay so that it doesn't interfere with the sail.
7. When changing tack I
a) as the jib comes across I switch the jib sheet to the other side (I use a circular sheet and the plastic clamcleat sheet 'winches' - there is very little tension in the sheet)
b) as the mainsail comes across I tension the slack backstay and then release the tight backstay so that now the pull of the sails on the mast is transmitted to the backstay on the other side.
8. Tension in the 'forestay' triangle can be adjusted by pulling/releasing the outhaul/tack.
9. When taking down the mast I drop & stow the foresail stowing the halyard/backstay lines beside the mast, tying them so that they stay there permanently & get rolled up inside the sail as it is furled round the mast - then they are there for next time, though actually it is easy enough to take the lines off.

It is quite possible to set up this entire arrangement without drilling a single hole (in an AI) and to rig & de-rig the whole thing whilst at sea (apart from the outhaul which you would need to set up before you depart, unless you are very agile). The only holes I have drilled are to place a padeye on the foredeck placed to better suit the jib I use. Pretty much everything else you need can be tied onto the boat with a bit of cunning.

My jib is an off-the-shelf jib from a Topper sailboat - it is the smallest one you can get for a Topper I think & is about 1.5-1.8sqm so ~doubles the sail area).
Here’s the photo:

This set up transforms the sailing performance of my Adventure in light winds - I use the mainsail only mast unstayed in 'stronger' winds and mainsail+jib with mast stayed in light winds. It would be easy to stay the mast without the jib simply by connecting the halyard directly to the outhaul to make up a forestay ‘triangle’.


Don't even think about it if you can't cope with vast amounts of line in the cockpit - there's so much that you need to be very methodical & it can get very tangled esp. round the Mirage pedals which could put you at serious risk of a bath if the conditions were marginal & you were trying to stow it all in a hurry/got whacked by a gust/squall/windshift.

PostPosted: Tue Sep 22, 2009 3:17 am 
Site Rank - Old Salt

Joined: Thu Aug 16, 2007 2:25 pm
Posts: 2464
Location: Central Coast NSW Australia
Wow Stobbo! :shock:
Thanks for that detailed and very informative post. You are the rigging man for sure! 8)
Looks like you have used the Hobie standard mast tube, AI furling drum and pre 08 mast base in your adaptor?
I like your use of the old windsurfer mast.
Looking forward to some on the water pics! :)

PostPosted: Mon Oct 26, 2009 8:13 pm 
Site Rank - Old Salt

Joined: Sun Aug 12, 2007 5:17 pm
Posts: 641
Location: Auckland NZ
More photos
Shows the 2-part halyard stowed alongside the mast so that it can be rolled up inside the sail as the sail is furled. The halyard is colour-coded red and green, the end that attaches to the sail has a micro snapshackle on it, then there's a bright blue bead which acts as a stop to prevent the sail going too far up to the mast top. The outhaul is the white line attached to the padeye in the cockpit towards the RHS of the picture.

This picture shows the foot of the jib when 'set'. You can see the outhaul which hauls the tack of the sail to towards the bow and tensions the forestay triangle from the bottom. You can see the two falls of the halyard/running backstays as they come down from the mast top - on the RHS of the picture you can see the taut one (in this case the red one) which is fixed to the boat beside the seat and in front of the mainsail you can see the slack one (green); this is attached to the other side of the boat beside the seat but it is left slack so as not to interfere with the set of the mainsail; during a tack you have to release the taut one and set up the slack one on the new windward side as you come about.

Here is the arrangement at the mast head - the colour is not good but you should be able to see the snapshackle attaching the two-part halyard to the top of the sail and the blue stopper bead preventing the sail going too high up the mast (so as to maintain a slot between main & jib). You can see the two halyard blocks, one on each side of the mast with the taut green fall of the halyard, i.e. the running backstay that has been set up, going down to the fixing point beside the pilot's seat on the left of the picture; you will have to imagine (because it is not very obvious in the picture) the red part of the halyard, i.e. the running backstay that is slack, going off down the other side of the sail to the fixing point on the other side of the seat.

Here's a view from the side of the cockpt seat looking forwards. You can see the hook to which the taut (green) backstay is attached (via a simple loop at the appropriate place in the line) and you can see the slack (red) backstay on the other side of the boat (attaching to a corresponding hook on the other side but this time using another simple loop at the end of the line) - so there are 2 loops in each line one at the end for when the backstay is set slack and the other further along for setting the backstay up taut. You can see the mid-way loop for the "taut" setting in the red line. Normally the "end" loop would remain in the hook at all times so that the backstay is always to hand. The hooks are attached to Hobie's screw-in padeye which has replaced the standard screw in cleat at that point (my boat is an AI hull and you can see the extra knob that is installed there for the Ama attachments which I use for clipping the paddle-retaining bungee to; on an Adventure hull you may have to think up a slightly different arrangement). Attached to the same padeye is the black plastic clamcleat thingy I use to hold the jib sheet with the white jib sheet running through it. The sheet itself is circular i.e. both ends are attached to the clew of the jib and the line goes around the mast - that way you can't lose the end). The plastic clamcleats are fine for the jib sheet because there is so little tension in the line: even when hard on the wind the sail only generates tiny loads - enough to get you moving nicely through the water but not to split a plastic cleat !

My next set of photos will be of the whole set up on the water I hope (It was a bit too breezy out on the water for both main and jib so I took these photos on land) !

PostPosted: Sat Dec 05, 2009 11:43 am 
Site Rank - Old Salt

Joined: Sun Aug 12, 2007 5:17 pm
Posts: 641
Location: Auckland NZ
On the water picture, sailing a very broad reach with purple jib and hobie main. Auckland City skyline & Skytower in the distance.

I have added some NEW 'on-the-water' photos to the slideshow above. These were taken by a kayaking friend on his 1st sailing expedition. Wind conditions were ideal & I was easily getting 4.5 to 5.0 knots on the GPS. My mate was not familiar with the camera so the shots are a bit distant but you will get the idea.

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