This is a common upgrade. The main sail can become a bit of a wrestle, especially whilst reefing in a rising wind. Although the standard system works it is not easy to set
This upgrade enables the lazy jack system to be single line through a spinlock clutch.
I had to configure this upgrade to cater for my boom tent- so this upgrade would fit any standard boat.
It is fairly simple:
1) I installed another cleat on the other side of the boom to the existing cleat used for the lazy jack line. These were bolted through the boom for additional security. Both lines are held on either side of the boom by a bow line. Note that this is one continuous line.
2) The existing fitting connected to the hounds was replaced by a Barton double swivel block.
3) The block for the throat halliard is lowered by approximately 300mm by the use of a wire strop. This removes any interference with the double block installation (2)
4) Both lines from the boom (either side of the gaff) are led through the double block. This is continuous line with the two ends of the lazy jack line being used to create the bowlines on the boom.
5) a single line is joined by the use of a sheet bend to the double line. This line is led through a block on the deck (now a tripple barton) to the clutch
6) The boom can now be simply lifted by pulling the line through the clutch.
The photographs below detail this upgrade.
Click on the for a simple narrative for each photo.