Dyneema

[David56]

Instead of going off thread on METAL BOATS line.
A comment on the thread mentioned he used DYNEEMA as a replacement for Rigging. I have never heard of this. If this is a good idea why isn't every one doing it. It really does make sense for a few reasons, spares, easy to replace,splicing etc.

Does anyone have some professional knowledge about the pros and cons
or personal knowledge of course.
cheers

[Jim Cate]

The practice is still kinda rare, but growing rapidly in the fleet. A good general source of info is from Colligo Marine. They supply cordage and fittings and lots of good advice. Have a look...

Jim

[44'cruisingcat]

More and more people are doing it. There's always some resistance to anything new.

I'm certainly going to look into in the next couple of years, I'll be getting due for a re rig then.

[billknny]

Everybody doesn't do it because it is not for every boat.

But, it has way more applicability than it currently sees. I rigged a 40 foot cruising ketch with dyneema. Some people thought I was nuts, but the boat LOVED IT. Losing about 200 lbs of weight aloft made a BIG difference in performance. She heeled less, and I was able to postpone reefing to much higher wind speeds than with a SS rig. The price was very similar to a re-rig with SS, so I felt it was a real win.

Now, you have to be ready for a complex change over. Another poster mentioned Colligo Marine. They know as much about this as anybody, and likely way more than your neighborhood rigger.

Be prepared to deal with some challenges. Creep is a long term issue. You either need lots of "throw" in your adjustment system or be prepared to have the lines re-spliced to shorten the most heavily loaded lines from time to time.

Do not expect to be able to splice at home for this application. The slices need to be heavily pre-loaded to avoid significant construction stretch upon installation.

[GrowleyMonster]

I have hanked jibs and need the backstay for HF, but thinking about replacing shrouds with dyneema once I know more about it. All the wire is original, 1979 vintage and really ought to be replaced.

[Paul L]

Originally Posted by GrowleyMonster

I have hanked jibs and need the backstay for HF, but thinking about replacing shrouds with dyneema once I know more about it. All the wire is original, 1979 vintage and really ought to be replaced.

What's an HF?

[wrwakefield]

Originally Posted by Paul L

What's an HF?

I suspect he is referring to using a wire backstay for a HF Radio [SSB] radio antenna...

Cheers! Bill

[kmacdonald]

It's great for adjustable back stays. Creep doesn't matter because it's adjustable.

[SailFastTri]

Originally Posted by GrowleyMonster

I have hanked jibs and need the backstay for HF, but thinking about replacing shrouds with dyneema once I know more about it. All the wire is original, 1979 vintage and really ought to be replaced.

Hanked jibs might be a reason not to use Dyneema on the jibstays. It's more resistant to abrasion than any other type of cordage, but not as resistant as SS. You could certainly use it on the other standing rigging. Speak with Colligo, they're the experts. Colligo Marine®

[Steven UK]

Look up ‘rigging doctor’ and ‘sailing zingro’ on YouTube, it will get you started and you’ll know what questions to ask... good luck.

Regards Steven

[Dave_S]

I intend to go that way late next year.

From my research creep is a bit of a variable. Current trends seem to be to over spec the dyneema to about 3 to 5 times the required strength to reduce creep. That makes the dyneema significantly larger in diameter which has the down side of increasing drag.

I believe the creep issue will be better controlled with development of the material because it is theoretically possible to use narrower dyneema for the required strength.

If the makers can develop it so it will reduce drag that will be a significant issue resolved and increase sales so there is a great deal of motivation.

I don't think retentioning the rigging is much of an issue so I will go with rigging on the narrow side. You can buy it pre stretched now but that doesn't mean it won't stretch, just that it will stretch less.

I expect a lot to change between now and then.

[Jim Cate]

Evans Starzinger described using bronze hanks on a Dux stay (staysail) with no chafe issues. Gotta admit that it is kinda scary, but Evans is a pretty reliable reporter.

Jim

[Steven UK]

Originally Posted by Dave_S

I intend to go that way late next year.

From my research creep is a bit of a variable. Current trends seem to be to over spec the dyneema to about 3 to 5 times the required strength to reduce creep. That makes the dyneema significantly larger in diameter which has the down side of increasing drag.

I believe the creep issue will be better controlled with development of the material because it is theoretically possible to use narrower dyneema for the required strength.

If the makers can develop it so it will reduce drag that will be a significant issue resolved and increase sales so there is a great deal of motivation.

I don't think retentioning the rigging is much of an issue so I will go with rigging on the narrow side. You can buy it pre stretched now but that doesn't mean it won't stretch, just that it will stretch less.

I expect a lot to change between now and then.

I agree with you but but You should be prepared to wait... I am also very interested in going this route but I think I’ll take a back seat and see what developers...

[kmacdonald]

My Capri came with a dyneema back stay and it broke at the upper splice. I wasn't sailing when it broke, it was in it's slip at the marina. My guess is the splice bury wasn't tapered properly. I made another back stay out of dyneema and it's been fine for 4 or 5 years so far.

It should be noted there was no indication of wear, chafe, or sun damage to the one that broke.

[Panope]

Originally Posted by Jim Cate

Evans Starzinger described using bronze hanks on a Dux stay (staysail) with no chafe issues. Gotta admit that it is kinda scary, but Evans is a pretty reliable reporter.

Jim

Jim, my sailmaker (Carol Hasse) says that if the hanks have not been used previously on a metal wire then there will be no problem using them on a Dymeema stay. I reckon a thorough polishing of the inner surface would make any hank ok.

Steve