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post #24 of Old 07-06-2014
knuterikt
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Join Date: Aug 2006
Location: Norway
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Furler for assymetric - update

I have sailed with my Facnor AFX 2500 since the May 2009.

This spring I decided to do some upgrades.

It has been a tremendous development on the construction of anti torsion rope in these five years.
To the right in this picture is the old rope - three layers
- core
- some rubbery sleeve (only to keep the fibers in a bundle)
- Cover
To the left the new rope - four layers
- core similar to the old
- Inner braid (white) made of some stiff thin fiber
- Intermediate braid (black) made of some stiff thin fiber
- Cover assimilate to outer on the old

The new rope is significantly better to resist torsion (might be unfair compare used to new - but I seem to remember that the old one was almost the same when new)


The endless furling line on the system had increased in diameter since new initially 8 mm now almost 9 mm and the surface had gotten "fluffy".
I decided to replace this, double braid polyester/polyester.
New ropes have been developed for this use also, I bought some Marlow ropes MGP furler 50 MGP Furler 50
It's made of VectranŽ / Polyester blend cover, Polypropylene Core
Here is a picture I took during the splicing, notice the tight braid on the core, will give better form stability.


In a system with endless lines it is important to have as little friction as possible in the system
In my old setup I had to double ball bearing blocks to lead the line back to the cockpit, It worked but the problem with blocks is that they only reduce friction when the rope is running over the wheel.
The block housing will induce friction if/when the rope rubs against it - I found that often my blocks would hang on the rope..
The furling line was/is lead more or less direct aft from the bowsprit along the cabin side to an attachment between my two sheet winches.
I got rid of the two blocks, replaced with
One Selden furling line guide attached to the tubing of my self tacker attachment.
One 50 mm SS ring hanging of the pulpit with a shock cord.
The selden furling line guide, this can be opened with one hand to take the line off.
Hopefully this will make me better at taking the hole furling system off when not in use..



This is a picture of the central furling line used on the Facnor system


The adjustable tack on my bowsprit, the combination of the stiff 10 mm Dyneema tack line and the distance between the two points (attachment and strop with thimble) prevent furler from twisting.
This way it's easy to adjust the tack height and thus the fullness of the sail.
I must pull the tack back down before furling.


The adjustable tack also give me a safe way to use the spinnaker boom on DDW.
I have a guy attached to the bottom of the furler(=tack), by easing the tack line and winching in on the guy I can pull the tack to windward and use it as spinnaker.
The tack is always ready to pull the tack/drum down to gybe or furl the sail.


Video showing the furler in action (no sail)


The tack of the sail


It was a little bit difficult to dismantle the system, it was put togheter using liberal amounts of locktite.
The roller bearing balls are made of delrin so it is important to be carefull with heat.
On assembly I decided to modify the design, replacing the set screw and locktite with a rigging bolt through the whole assembly.

The special clamping tool made to dismantle the top swivel (you can use a spanner on cone, the the other part is round).


From the other side
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