Introduction

Version 2, January 2003

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The current Blaze ‘X’ configuration with its semi-soft 10.0m sail has become standard in the class since its introduction in early 2001.  It replaced the original 10.4 fully battened ‘hard’ sail that, while powerful, was not ideally suited to the boat in some conditions.

Early boats can be made very competitive by converting to the current sail specification and this is an excellent way to end up with a low cost entry to the class.  In March 2001 the, then new, ‘X’ rig was supplied with a distinctive ‘kicker strut’ that helped reduce control line loadings.  This required a second gooseneck to be attached to the mast in addition to a repositioning of the original gooseneck as described in this document.  This system is highly effective and well proven.

Some have since experimented with a much simpler modification which gives a sufficiently powerful kicker without the complication of the strut.  This is permitted by our class rules and is now the recommended way to modify an earlier boat to current specification.

The current ‘X’ sail (10.0m) requires a lowering of the boom to accommodate it’s longer luff.  The M7 mast, the boom plus various other fittings are reused.

Modifications are made to the following elements:

Mast: Gooseneck position lowered

Boom: Kicker attachment and arrangement

Tools: 

• Drill with small bits (you need a 5mm for rivet holes) and to remove existing from Boom and Mast.
• Hacksaw
• Rivet Gun – suitable for 4.8mm rivets (you will need 9 in total)

Method:
We will reuse as many items from your existing boat as possible. The good news is that the modification has been designed to reuse the expensive items such as Mast and Boom plus as many small items as possible from your pre-existing kicker system.  You should only have to supply rivets, some high performance and low stretch line like ‘Vectran’, an additional single block and maybe a replacement for one likely to be previously damaged.

Boom

• Drill out the retaining Rivet attaching the kicker webbing to the boom.
• Drill a new hole in the boom 920 mm from the boom end – ie further along the boom than the original rivet hole. The aluminium boom has an angled cut on its underside to allow the ‘drop’ of the control line to the deck.  (Where a carbon boom has been supplied this is ‘square cut’).  The measurement should be from the END of the boom ignoring this cut-out. It is usually best to drill a pilot hole first with a small bit before using a larger 5mm one.
• Rivet the webbing with a 4.8mm rivet. You may choose to add a washer under the rivet to spread the load over a wider area of the webbing.
• Optionally fill in the ‘old’ hole with a rivet – this simply tidies up the hole.

Mast

This is best done with the mast in position.

• Drill out the existing rivets on the pre-existing gooseneck. Be careful not to damage the fitting during this process. It may help once the heads are removed to punch the stubs through with either a punch tool and hammer or a suitable old bolt and hammer.
• Clean the area where the gooseneck was located and fill the 4 holes left with rivets – this ensures the mast tube remains sealed.

You now have to relocate the gooseneck.

• Measure from the foot of the mast and mark with pencil the following position -  420mm. This will be the position of the repositioned gooseneck.
• Hold the gooseneck so that its mid-point is aligned with the pencil mark. . Drill a single hole using the fitting as a template in the mast and place a rivet in the hole. DO NOT USE THE RIVET GUN JUST YET ! - Drill a second hole on the other side of the track in each in a similar fashion and again place a rivet to maintain the position of the gooseneck.
• Once you are satisfied with the alignment with just 2 loose rivets you can now use the gun on the first – ensuring the second still locates the fitting. Then go on to the second one. Once these are completed the positions are certain and you can drill and ‘gun’ the 3rd and 4th rivets. 
  

Kicker

Firstly prepare the following items from the old arrangement:

• Take your existing kicker to pieces.  Recover both the double block and the single with becket from either end of the wire – you will have to hacksaw the wire to do this.
• Examine the block with becket carefully – many are already distorted and should be replaced with a good quality and possibly larger equivalent.  The double should be in reusable condition.
• You will need to source an additional single block.  This could either be a ‘high load’ type or good quality ‘normal’ one. (The diagram suggests this should be ‘high load’.
• The existing high load wire block that was attached to the webbing strop should be retained and used.

Rigging it all up
The system is relatively simple – the original (8:1) configuration is largely copied.  This had a single 2:1 ‘cascade’ above a 4:1 arrangement using the double and becketed single.  This is copied but with addition of a second cascade to give a 16:1 system.

The original wire can be replaced with new for the double cascade arrangement or you can use one of the new hi-tech line equivalents like vectran that you can tie yourself.  If you have a ‘fid’ you can produce a very professional looking arrangement with splices in this rope.  If you do not then you can resort to knots (though this may reduce the strength a bit – but loadings are not THAT high)

Good luck with the modification, its well worth the effort and will, together with the new sail, greatly increase your enjoyment of this fantastic boat.  There is a certain satisfaction in modifying your own boat and ending up with a highly responsive, fast modern racer – with a new sail and at very modest price.