Well it is only one mans idea of what to put above a footy hull.
What do we want in a rig anyway?
something to hold some sails up and a way of coaxing the sails into the shape needed for best forward propulsion.
As lightweight as possible is always good, quickly made would be good,Ive spent hours making rigs in the past.
a rig that can be quickly exchanged for another between races.
Heres a bit about my “solution”
In broad terms it is a swing rig without a mast and a solid forestay!
a single sail is set on the forestay and the whole rig pivots around a point where the mast ought to be.
The Forestay( refered to as the mast from now on) is angled back to give quite a rake, the mast is made from 3mm carbon tube in the current version.
The boom is made from 1.5mm carbon rod and there is a Z shaped peice of s/s wire (1.5mm)connected the two together.
The Z shaped wire starts at the bottom of the hull and is sharpened in order to pivot easily.it comes up through a small peice of brass tube glued through the deck.
As the wire exits the deck it is bent and goes forward 100mm in my case,it is then bent upwards for the carbon tube to sit over as the mast step.
The carbon rod boom is glued onto the bent wire and carbon tows added to taste,the ammount of carbon has a direct bearing on how much the rig is allowed to twist.
Footys are very short and differcult to handle,this rig solves many handling problems as it smooths out the variations in the breeze that the boat is feeling.These things happen so fast on small boats that it is impossible to react to them so the rig must be automatic. The latest versions can sail downwind without diving at all,the rig absorbs the power from the gusts and returns the power to the boat when the gusts ease.
You get extra power at the end of gusts as the rig comes upright again.
The hardest part is matching the hull/keel to the flexibility of the rig.
The size of the wire and ammount of carbon tow can be varied to get as little or as much stiffness as required.
OK…as you will have picked up it is the bent wire twisting that depowers the rig,not mast bend.I would like to have some mast bend as well but havn’t been able to match the sails to the mast well enough at this size yet.
Since the mast isn’t bending making the sail is quite straight forward.
I use a simple one peice pocket luff sail made from Florist film.
The Florist film is cheap and stiff enough not to need battens,you could use lighter materials but this stuff sets up in a nice smooth shape easily.
The sail is simply taped to the ttop of the mast,gravity holds it down without need for a downhaul.The stiffness of the pocket luff makes sure the sail will not ride up the mast under pressure.
The outhaul is simple another peice of tape holding the sail to the boom,by varying the position of these 2 peices of tape(mast and boom) you can vary the twist and camber in the sail(honestly:))
The mainsheet simply hooks over the bent wire before stepping the mast.
Changing to a smaller rig means steping the new mast on the boom and taping the sail into position.Really keen guys will have multiple booms/sails etc.
The last peice of the rig is a small counter weight on the end of the boom to balance the rig perfectly.
The rig pivot allows the CE to be more or less above the boat for downwind work,the offset pivot also reduces sheet loads enabling the use of a lighter than normal sail winch.
You can see the mast bend off at the bottom as gusts hit the boat,the boom also bends opening up the leech,as the gust eases the rig comes upright again giving back the energy.This automatic gust response smooths out the handling of small boats a treat,the boat will sail upwind completely hands off giving the sailor more tome to think about more important things on the racetrack,This may not be the fastest rig in absolute terms but freeing up the sailors mind for other duties makes the overall package very competitive.
The whole rig incl sail can be made in about half and hour.
I will give some dimensions and angles in a latter post.