Daggerboard raising line...26M

david.claassen's picture

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  • Member Discussions:Technical

or is this a halyard? Hmmm...

I feel that it is time to replace the line on my daggerboard. Has anyone used one of the more modern types of rope (Dyneema?) for this? It seems that this should be one of the strongest lines on the boat, because, if it parts, you could be in some serious trouble. I had a block fail on mine a couple of years ago during a receeding tide in the Walton Backwaters..good thing I had a bit of water under me and a spare block!

Thoughts?

David Claassen

"Logan's Run"

2006 26M

3 Comments

I replaced mine a couple of

I replaced mine a couple of years ago. I cut a short length off the old line and took it to the chandlery. I wanted it pre-stretched and soft to handle and the diameter is important so as to be able to thread it through the channel in the dagger board, so I bought what the chandlery people recommended. The frightening thing amongst all this technology is that there is just about enough room to squeeze a granny knot at the end of the line into the recess ( so as not to hinder the board being pulled up or dropped) to jam the line into the board. I tried various knots and this was the only one I could squeeze into th recess. The board is still there!

It is a fiddly process so lots of patience needed.

Good Luck David

Simon

Hi Guys,

Hi Guys,

Like you Simon the only knot I could fit in was a simple thumb knot. I tried to put a figure of eight on the lines when I made the new dagger boards and failed even with a slightly larger side access hole. But the simple knot does work and seems to be safe the only down side is that it pulls so tight as to be almost impossible to undo at a later date. If you are careful you can leave a relatively long tail beyond the knot and thread this in first to ensure the knot isn't too close to the end of the line. A good quality pre stretched line is fine. The holes are 11 -12 mm dia so a 10mm dia rope is normally used. Dyneema can be used but is unnecessarily expensive and not a particular advantage. The new line wants to be a good tight fit on the hole in the top of teh board to minimise chaffing.

David's note above suggests that a rope failure is a disaster but there should be two lines one is a limit line which sets the maximum depth the dagger board can be lowered to and the other is the uphaul. I set our uphaul line with a knot (or a pully if you use one) in it so that even if the limit line fails the dagger board can't drop too low or out. The knot is about 50mm longer than the limit line so that it acts as a fail safe. The limit line length is important as if you let the board lower too far you can damage the board as well as the casing or get it stuck. Keep the new lines exactly the same length as teh old ones.

I agree with Mike.  The limit

I agree with Mike. The limit line which rarely takes a high down force dud to bouyancy as the board sinks, should not fail. For the uphaul line i usr a pulley having shortened the original line . I have 3 to one advantage on the uphaul so it goes up without much effort. Don't try to force it up when craft is motoring or heeling at all since friction will be too high.

Roly