Reacher tack cord keeps breaking. ?

[Dave_S]

This is the second time this has happened.

Where the tack of the reacher attaches to the furler it has 5mm dyneema cord bound 4 times and it just snaps. No real event, you just notice the sail has moved up the stay at the foot. This must have broken last time I used it and I didn't notice when I wraped it up as it has somehow furled unevenly top to bottom. When I unfurled it, it was fully unfurled at the top but still had 6 turns to go at the foot.

I don't imagine the cord isn't strong enough for the inline load and I can't see anything obvious it would be chafing on (the end of the stay does have the eye bound in some cord that looks to be designed to prevent chafe but maybe its incompatible with the dyneema?) but I'm thinking it might be something I'm doing when I furl it. It looks like the twisting has over stressed it...... I'm not sure?

I try to wrap it up quite tightly with some drag on the sheet then I over furl it about 4 more turns to help stop the sail catch in the.wind.

It maybe that tieing it off with cord wasn't how it is meant to be attached, I just followed what was there.

Any ideas?

[billknny]

Originally Posted by Dave_S

This is the second time this has happened.

Where the tack of the reacher attaches to the furler it has 5mm dyneema cord bound 4 times and it just snaps. No real event, you just notice the sail has moved up the stay at the foot. This must have broken last time I used it and I didn't notice when I wraped it up as it has somehow furled unevenly top to bottom. When I unfurled it, it was fully unfurled at the top but still had 6 turns to go at the foot.

I don't imagine the cord isn't strong enough for the inline load and I can't see anything obvious it would be chafing on (the end of the stay does have the eye bound in some cord that looks to be designed to prevent chafe but maybe its incompatible with the dyneema?) but I'm thinking it might be something I'm doing when I furl it. It looks like the twisting has over stressed it...... I'm not sure?

I try to wrap it up quite tightly with some drag on the sheet then I over furl it about 4 more turns to help stop the sail catch in the.wind.

It maybe that tieing it off with cord wasn't how it is meant to be attached, I just followed what was there.

Any ideas?

There are really only two possibilities.

You are right, the dyneema is strong enough it is not failing because it is overstressed. Most likely it is chaffing, either with itself as things move, or with one of the end fittings.

Or the knot you are tying is slipping. Dyneema is famously slippery and hard to knot.

[thinwater]

Originally Posted by billknny

There are really only two possibilities.

You are right, the dyneema is strong enough it is not failing because it is overstressed. Most likely it is chaffing, either with itself as things move, or with one of the end fittings.

Or the knot you are tying is slipping. Dyneema is famously slippery and hard to knot.

Knots don't just slip in Dyneema (most do). In ANY high modulus fiber, most knots weaken the line not just 40%, but more like 65%. 5mm Dyneema is not that strong, viewed in that light. Perhaps an eye that is in turn tensioned by a light cord lashing.