Making a sail for Illusion

Phil OxBorrow cut down a Mirror sail to a lug sail for his 16ft canoe. He lent it to me and it worked very well on Illusion so I decided to make a copy knowing that Mirror sails are easily and cheaply available. Ian Hylton from the DCA kindly sent me a spare Mirror sail in return for a donation to the Lifeboats Charity, that I happily made.

Here is Phil's sail - you can't see the seams but it is cut along the 3rd seam leaving the bottom 3 panels.

And here is my prototype cut with a peak about 1ft higher than the 3rd seam and a steeper angle. This will give slightly more area and a slight benefit on sheltered rivers:

The mast length is limited to a tad over 10ft/3m as I intended it to stow inside the boat. In hindsight a slightly longer length would allow me to use more of the Mirror sail's area; however a standard windsurf mast extension gives me extra length (I may need to reinforce the glassfibre mast at the foot).

The yard is aluminium recycled from a shower enclosure. It is lightweight and should be strong enough. For the boom I will laminate two spare lengths of 26mm x 12mm which is the regular door jam size in the UK. That should have the right balance of strength and light weight - the sail attaches at the clew and tack and the sheet will be at the end of the boom, so there will be very little bending moment and I don't need a heavier boom.