380 S2: Dyneema rigging

[Trevor Doble]

Hi all

We are having our 380 rerigged in the next couple of months, and I have been toying with the idea of going with Dyneema. Most of the advice I have had is "why would you?" but having spoken to a few owners (not cats) they say changing to Dyneema was the best move they have made.

I will probably just replace the current stainless with stainless, but I'm interested to hear if any 380 owners have switched to Dyneema and what have been their experiences?

Thanks
Trevor

[neilpride]

The question would be,, what are you looking for with that change?

[Tupaia]

A huge reduction of weight aloft.

Easy to replace shrouds. Diamonds can be changed but there is potential for chafe at terminals or on spreaders.

[Trevor Doble]

Originally Posted by neilpride

The question would be,, what are you looking for with that change?

Hi Neil

As I say, not convinced it is the right thing to do hence looking for feedback from anyone who has it.

Apart from the obvious weight advantage, the owners I have talked to have said maintenance is virtually non-existent once you have set it up correctly. The stainless rigging on my boat is 14 years old and still in pretty good nick, so I would have no problems replacing with stainless. The local rigger I spoke to (Peter Greig) is very experienced with Dyneema and his cost estimate for Dyneema was very comparable to what I have been quoted for stainless. I'm really looking for disadvantages anyone might have found other than initial cost and potential chafe - just want to make the right decision as it is on the baot for a long time

This is from an Q&A Peter did last year with Wichard Pacific:

I am on my 80th job with Dyneema…only three of those are racing boats ! Yes it is absolutely reliable for the cruising market, in 17 years I have not seen a single failure. I have five cruising furlers I have done in the last three years which are retrofitted with Dyneema forestays. The market is cruising boats, however more and more racing boats are attracted to the benefits of Dyneema.

Thanks for responding, it is all food for thought...

[Trevor Doble]

Originally Posted by Tupaia

A huge reduction of weight aloft.

Easy to replace shrouds. Diamonds can be changed but there is potential for chafe at terminals or on spreaders.

Thanks.

Do you have experience with Dyneema rigging?

[Tupaia]

Originally Posted by Trevor Doble

Thanks.

Do you have experience with Dyneema rigging?

Yes.


I would recommend Mike Strong at StrongRpoe.com 0405 406 309

[Trevor Doble]

Originally Posted by Tupaia

Yes.


I would recommend Mike Strong at StrongRpoe.com 0405 406 309

Thanks, I will look into them - they don't list a location on their website, do you know where they are based?

Also, would appreciate your personal experience with Dyneema - was it on a catamaran?

[Tupaia]

Originally Posted by Trevor Doble

Thanks, I will look into them - they don't list a location on their website, do you know where they are based?

Also, would appreciate your personal experience with Dyneema - was it on a catamaran?

He works out of Sydney



Been excellent. Saved in excess of 30kg aloft and very stable.
Dynex Dux overbraided with Dynex finished with hi load stainless thimbles at each end.


I would be interested in how "Peter" has achieved Dyneema furling forestays. I did not think this was possible.

[markxengineerin]

"Easy to replace" is a myth in my opinion. It's more labor intensive than replacing wire in that it needs to be pre-stretched at a high and accurate load (ie with a come-along/load cell), then measured before it is disturbed (ie coiled), then spliced precisely to get the appropriate length, assuming you want to keep turnbuckles and not go with lashing, which comes with a different set of challenges. The setup to pre-stretch is not trivial, so it's not like you can just carry a bunch of it around and make perfectly good shrouds on a remote island. It's not a bad thing to have dyneema around in an emergency, but it's certainly not "easy to replace" compared to wire.

Chafe is a big potential problem- 99% of the time it will be fine, but that 1% when you're not paying attention, and something happens, it's something to consider. One more thing to worry about on a boat full of entropy.

[Tupaia]

Originally Posted by markxengineerin

"Easy to replace" is a myth in my opinion. It's more labor intensive than replacing wire in that it needs to be pre-stretched at a high and accurate load (ie with a come-along/load cell), then measured before it is disturbed (ie coiled), then spliced precisely to get the appropriate length, assuming you want to keep turnbuckles and not go with lashing, which comes with a different set of challenges. The setup to pre-stretch is not trivial, so it's not like you can just carry a bunch of it around and make perfectly good shrouds on a remote island. It's not a bad thing to have dyneema around in an emergency, but it's certainly not "easy to replace" compared to wire.

Chafe is a big potential problem- 99% of the time it will be fine, but that 1% when you're not paying attention, and something happens, it's something to consider. One more thing to worry about on a boat full of entropy.

Mike Strong, pre measured, pre stretched, spiced thimbles and braided covers. What's not easy?

[markxengineerin]

If dyneema is easy, then stainless is easy too, or "easier" depending on your perspective. My rig is diy dyneema, and in comparison to diy sta-lok / wire I personally find the dyneema more difficult.

If you pay someone else to do it, then it's a moot point.

[Tupaia]

Originally Posted by markxengineerin

If dyneema is easy, then stainless is easy too, or "easier" depending on your perspective. My rig is diy dyneema, and in comparison to diy sta-lok / wire I personally find the dyneema more difficult.

If you pay someone else to do it, then it's a moot point.

Prices of pre made dyneema rigging is comparable with ss but with massive savings in weight and transportation costs.


If you are making your own then you have to compare accurate cutting of wire 12mm ss and dealing with large StaLok fittings is not user friendly, vs equivalent spicing of dyneema and getting the right length. If the supplier is any distance or overseas transporting ready made or even just the ss wire is a nightmare, definitely not air freight.

[markxengineerin]

Yes fair points, depends on perspective and circumstances

[goat]

Originally Posted by markxengineerin

"Easy to replace" is a myth in my opinion. It's more labor intensive than replacing wire in that it needs to be pre-stretched at a high and accurate load (ie with a come-along/load cell), then measured before it is disturbed (ie coiled), then spliced precisely to get the appropriate length, assuming you want to keep turnbuckles and not go with lashing, which comes with a different set of challenges. The setup to pre-stretch is not trivial, so it's not like you can just carry a bunch of it around and make perfectly good shrouds on a remote island. It's not a bad thing to have dyneema around in an emergency, but it's certainly not "easy to replace" compared to wire.

Chafe is a big potential problem- 99% of the time it will be fine, but that 1% when you're not paying attention, and something happens, it's something to consider. One more thing to worry about on a boat full of entropy.

I agree 100% about the issue of chafe and that it is something to watch out for.

I had my SS backstay fail approximately 1000 miles off of the Baja. Luckily I had a roll of Dyneema and whipped up a new stay in an hour. Not knowing the length I asked Pythagoras for his opinion. I knew the height of the mast as I just (luckily) had mast steps installed. Measured back from the mast, did the calcs, stretched as best I could with samson post and winches and attached it to the existing turnbuckle. That allowed me to continue the next three thousand miles to northern B.C. by-passing Hawaii. Since that scare a year and a half ago, I've replaced all my shrouds with dyneema and just have the forestay and a newly built bobstay in stainless. A couple months ago, on my way back south, a vicious knock down two hundred miles southwest of Vancouver Island reinforced my trust.

Use good heat stretch like Sampson sts-hsr, Dynice Dux or equivalent.

goat

[markxengineerin]

Wow quite a story! I do think dyneema could make a great emergency/temporary stay, especially if spliced using a quick and dirty method with a simple bury and no taper. That way if it's the wrong length or changes length, it can be easily adjusted, and there's no need to hit the right length on 1st try. Also, nobody is going to care about creep over years in an emergency situation, so the target goes from +/- "something smaller than turnbuckle travel" to +/- turnbuckle travel, in my case about 4". I plan to buy a spare length just for this purpose.