Any Updates on Synthetic Rigging ?

[Merit 25]

Only time when you need to worry about creep is when the static load gets above 10% of the breaking strength. So you size you're shrouds accordingly. If it stays under that, then creep really isn't an issue.

[Jmolan]

Glad to see the discussions continue. The advances and advantages are light years ahead of steel. The adaptations and innovations will continue.....My life and lively hood depends on the absolute reliability of the stuff. We can use anything rope/cable/material in the world, in Bering Sea fisheries. We continue to use and abuse Dux year after year.....:-)

[Jmolan]

200 miles north of the Aleutian Island chain, deep in the darkness of a Bering Sea winter, 0300 hrs. F/V Arcturas hauls 150 ton bag of pure pollack. All lift lines, bag, rib lines, winch lines, net, rigging....all, Dynex, and Dux........when it really counts, safety, energy saved, work load....use the best ......:-)

[Jmolan]

Ok one more, then I will go away again. The 25mm Dux above his head has replaced 25mm steel cable for the main wires. At 1,000 fathoms each side on the main drums, used to hold the net behind and wy below the boat.....the weight saved is off the chart....the net (also Icelandic, Dux) can spread to previously unimaginable proportions due to the shedding of all the cable weight. On deck you can see the main 2" lifting strap on the 150 ton bag. The main lifting winches run 1 1/4" covered Dux, they have 3 years of year round work on them so far....still in great shape......ice, rusty decks, backlashes drums, everything a workboat can throw at it. It is the STUFF!

[delmarrey]

Originally Posted by Merit 25

Loos gauge calibration sheet:
http://www.colligomarine.com/docs/mi...sGaugeCals.pdf

The difference between SK75 and SK75 that has been heat treated and pre-stretched is amazing. The strength is much higher and the creep is much lower. There still is creep, but no where near the amount that non-heat treated stuff is. Don't use the regulat 75 for standing rigging. Lifelines are fine.

If you want zero stretch and creep, you need to go PBO. But that is a small % of racers who can justify that cost.


How so? Could you provide an example?

Thanks for that! I've filed it away.
So, one can use the loos gauge! I guess if I had done the research myself I would have found it.

[s/v Jedi]

Originally Posted by Merit 25

Only time when you need to worry about creep is when the static load gets above 10% of the breaking strength. So you size you're shrouds accordingly. If it stays under that, then creep really isn't an issue.

Indeed. My rig has no backstays and thus my capshrouds are 12mm Dyform tensioned to 20% of breaking strength. If I want to replace that with DD and stay under 10% static load, I'm gonna need something like 1" DD or even bigger; I forget the outcome of the math but it was too much imo.

[Mark Johnson]

In discussions about synthetic VS SS wire, the often omitted problem with DUX is if the boat must go through a large temperature range. Where I live in NC, it can change 100 degrees F over the year, and my actual sailing temperature range might be 60 degrees F of change. (45-105 degrees)

With "wire" on a metal mast, they expand and contract more or less together, so the tune of the rig doesn't change with the seasons or time of day. At least not where I ever noticed it. This is not true with DUX.

We built our boat and launched her in '96, and after > 20,000 sea miles, are about due for a wire change. Still, using 316 SS wire, with all StaLocs, (Properly sealed), we have no rust or meat hooks. The wire looks "perfect", but it has been 17 years, so is on my list, nonetheless. I will re-use the StaLocs...

A couple of years ago I replaced my SS running backs with DUX, and love it for that application. Being so light, it doesn't flop around when in the slack "stored" position.

I considered it for the rest of the rig as well, until I noticed this coefficient of expansion incompatibility between DUX stays and the mast's aluminum extrusion.

I can make up my running backs, and really snug them up good with the folding handle "quick adjust" turnbuckles. I mean TWANG! This is with an afternoon temp of say 90 degrees. IF it was in the mid 50s the next morning, these same runners would be sloppy loose and with two fingers go in a 1' circle! THAT'S how much difference in tune you get over 40 degrees!

With my runners, it is no problem, as I can adjust them by hand in 30 seconds. Also, I change their tension regularly, depending on whether they are being used or stored.

IF I used DUX on the rest of my very tall / skinny double spreader rig, which is quite tune sensitive, it would be a disaster unless I re-tuned her regularly. (With SS wire, I have re-tuned the rig only twice, in 17 years).

To keep my mast in column, I need my uppers really tight, compared to the intermediates and lowers. Keeping her in tune is easy with wire, year round, and in any temperature, she stays straight. This could not be said with DUX, IF it is stressed as much, over as broad a temperature range, without re-tuning.

Many rigs, (like front stayed triangular rigged rotating masts and such), have slack leewards, OR such a stout extrusion, (often with diamonds), that these changes in tune could be tolerated. I know that a lot of boats do fine with synthetics, and for some, there is a lot to be said for the stuff.

I just want to point out that IF you plan World cruising, with a broad temperature range, (or locally for that matter), AND you have a tall "tune sensitive" rig, like we do, then wire is still the better choice IMO... from hot season to cold season.

On my most important wires, the uppers, I will be switching up a size, and to "Compact Strand" as well. In a fun daysail situation, I can then fly full sail in up to 35 knots of wind, and being a tri, the boat will stand up to it. I don't want any surprises, because it is a colder day than when I tuned the rig!

BTW... When comparing "weight savings aloft" of synthetics, it is a moot point to compare it's weight to SS wire alone. With all of the radar, steps, lights, antennas, etc., that go onto a cruising boat's mast, PLUS the extrusion, the shrouds and stays are a very small portion of the weight of a complete rig. I may over time, switch to lighter running rigging and sails, for a similar weight advantage...

Mark

[boatsail]

Originally Posted by Mark Johnson

In discussions about synthetic VS SS wire, the often omitted problem with DUX is if the boat must go through a large temperature range. Where I live in NC, it can change 100 degrees F over the year, and my actual sailing temperature range might be 60 degrees F of change. (45-105 degrees)

With "wire" on a metal mast, they expand and contract more or less together, so the tune of the rig doesn't change with the seasons or time of day. At least not where I ever noticed it. This is not true with DUX.

We built our boat and launched her in '96, and after > 20,000 sea miles, are about due for a wire change. Still, using 316 SS wire, with all StaLocs, (Properly sealed), we have no rust or meat hooks. The wire looks "perfect", but it has been 17 years, so is on my list, nonetheless. I will re-use the StaLocs...

A couple of years ago I replaced my SS running backs with DUX, and love it for that application. Being so light, it doesn't flop around when in the slack "stored" position.

I considered it for the rest of the rig as well, until I noticed this coefficient of expansion incompatibility between DUX stays and the mast's aluminum extrusion.

I can make up my running backs, and really snug them up good with the folding handle "quick adjust" turnbuckles. I mean TWANG! This is with an afternoon temp of say 90 degrees. IF it was in the mid 50s the next morning, these same runners would be sloppy loose and with two fingers go in a 1' circle! THAT'S how much difference in tune you get over 40 degrees!

With my runners, it is no problem, as I can adjust them by hand in 30 seconds. Also, I change their tension regularly, depending on weather they are being used or stored.

IF I used DUX on the rest of my very tall / skinny double spreader rig, which is quite tune sensitive, it would be a disaster, unless I re-tuned her regularly. (With wire, I have re-tuned only twice, in 17 years).

To keep my mast in column, I need my uppers really tight, compared to the intermediates and lowers. Keeping her in tune is easy with wire, year round, and in any temperature, she stays straight. This could not be said with DUX, if it is stressed as much, over as broad a temperature range.

Many rigs, (like front stayed triangular rigged rotating masts and such), have slack leewards, OR such a stout extrusion, (often with diamonds), that these changes in tune could be tolerated. I know that a lot of boats do fine with synthetics, and for some, there is a lot to be said for the stuff.

I just want to point out that IF you plan World cruising, with a broad temperature range, (or locally for that matter), AND you have a tall "tune sensitive" rig, like we do, then wire is still the better choice IMO... from hot season to cold season.

On my most important wires, the uppers, I will be switching up a size, and to "Compact Strand" as well. In a fun daysail situation, I can fly full sail in up to 35 knots of wind, and being a tri, the boat will stand up to it. I don't want any surprises, because it is a colder day than when I tuned the rig!

Mark

Is there a reason you chose turn buckles instead of lashings by your turnbuckles? I am thinking ofndoingnmine in synth. And would be thankful form your reasonimg, logic and experiences. The reason I figured on lashings instead of turnbuckles is mainly due to more ability to have variancesand make c anges

[Mark Johnson]

Boatsail,
I would not consider lashings personally, especially not on a complex or tune sensitive rig. The lashings mainly make up for the difficulty in making synthetics turn out EXACTLY the length you want, and they also allow more adjustment range to deal with creep.

IF it was a a rig like a triangular stayed wing mast, that flops over when you tack, Or an equally tune "Insensitive" rig... I'd say go with lashings. Otherwise...

You will have these temperature changes I mentioned to adjust for seasonally at least, AND you will have to take up the rig just a bit over time, to deal with "creep", which synthetics are prone to. If you go WAY oversize on synthetic rigging (as recommended to minimize creep), you have relatively huge rigging in diameter and windage. Also, If it is a tight static loaded rig, you will still need to tighten it a couple of times a year due to creep.

If you have a rig that is appropriate for synthetics, and start out with turnbuckles 3/4 open, then you should have enough adjustment room for the rigs 7 or so year max lifespan, and these frequent adjustments can be done evenly.

With greased turnbuckles, you can take two turns on the port shrouds, then two on the starboard shrouds. This is even, and the mast remains straight.

NOT so with lashings! You can't come close to a tight rig with lashings, unless you go sailing on a very windy day, then take the slop out of the leeward shrouds. Then do the other side. Next is the same trick with the lowers...

Doing this with the mast ending up as straight, and vertical as you can achieve with turnbuckles, is just not possible, IMO... Now, think about doing this several times a year!

Also, the weight savings of lashings over turnbuckles is relatively meaningless, because it is weight on deck, not aloft, where it increases pitching.

If you are sold on synthetics, do yourself a favor, and use turnbuckles! There are exceptions of coarse...

Mark

[sabray]

Thanks mark well said. I use turning blocks on my dyneema running backs and its a treat. Used amsteel for replacement on my steering cable 5 years ago? Vouch for the thermal issue/ though mine was more of a creep and thermal issue. Its been fine sense usually tension it a few notches at the end of the season.

[estarzinger]

Some data from DSM (makers of the dyneema fiber) on impact of UV on strength. Higher than I would have guessed.

[s/v Jedi]

Originally Posted by estarzinger

Some data from DSM (makers of the dyneema fiber) on impact of UV on strength. Higher than I would have guessed.

Yes, but that assumes that every fiber is exposed. I believe that only the outer fibers are exposed and protecting the fibers underneath.

Did anyone test old dyneema? I now have 8 year old runners that have been in the tropics exposed to UV since day 1....

[Tristan]

Originally Posted by estarzinger

Some data from DSM (makers of the dyneema fiber) on impact of UV on strength. Higher than I would have guessed.

Attachment 59984

I'm sure it also strongly depends on the type and color of the coating - black should be the best

[Mark Johnson]

Originally Posted by s/v Jedi

Yes, but that assumes that every fiber is exposed. I believe that only the outer fibers are exposed and protecting the fibers underneath.

Did anyone test old dyneema? I now have 8 year old runners that have been in the tropics exposed to UV since day 1....

Could be fine? IF it is constructed like Dux, however, then the inner fibers ARE sometimes on the surface, then they go back in, then they're on the surface again, as it works it's way down the shroud. Just like the saying about a "chain and it's weakest link"... Logically, If 80% of the rope is exposed to UVs in numerous but small areas all along the length of a stay, then that 80% of the synthetic might as well be "totally exposed" as far as strength is concerned. The shielded strong fibers, will not keep that fiber from breaking at a weaker exposed point.

Of coarse a sheath takes care of the UV issue, IF it is totally opaque (= black), replaced as needed, and you can live with the huge increase in diameter (= windage). This still leaves the mast to synthetic's coefficient of expansion "incompatibility issues", however...

UV BARRIERS:
Remember... white or light colored Sunbrella sail covers, only protect sails a fraction as much as a totally opaque = dark colors do. The Sun shines right through white fabrics, white plastics, synthetics, and white paint. This is why I use Forrest Green canvass everywhere, and under my white LP paint, use several coats of grey primer, to protect the epoxy/glassed hull underneith.

The cumulative UV damage to all of the plastics on our boats, which includes the FRP hulls, or wood/epoxy skin, AND synthetics of all kinds, is far more than one might think. The extremely gradual nature of it, makes UV damage, "out of sight, out of mind", until it IS in sight. Then it is way too late.

Synthetic rigging may be the right choice for some folks, but just like with SS wire, all of it's pros & cons need to be taken into account.

Mark

[s/v Jedi]

Originally Posted by Mark Johnson

Could be fine? IF it is constructed like Dux, however, then the inner fibers ARE sometimes on the surface, then they go back in, then they're on the surface again, as it works it's way down the shroud. Just like the saying about a "chain and it's weakest link"... Logically, If 80% of the rope is exposed to UVs in numerous but small areas all along the length of a stay, then that 80% of the synthetic might as well be "totally exposed" as far as strength is concerned. The shielded strong fibers, will not keep that fiber from breaking at a weaker exposed point.

Of coarse a sheath takes care of the UV issue, IF it is totally opaque (= black), replaced as needed, and you can live with the huge increase in diameter (= windage). This still leaves the mast to synthetic's coefficient of expansion "incompatibility issues", however...

UV BARRIERS:
Remember... white or light colored Sunbrella sail covers, only protect sails a fraction as much as a totally opaque = dark colors do. The Sun shines right through white fabrics, white plastics, synthetics, and white paint. This is why I use Forrest Green canvass everywhere, and under my white LP paint, use several coats of grey primer, to protect the epoxy/glassed hull underneith.

The cumulative UV damage to all of the plastics on our boats, which includes the FRP hulls, or wood/epoxy skin, AND synthetics of all kinds, is far more than one might think. The extremely gradual nature of it, makes UV damage, "out of sight, out of mind", until it IS in sight. Then it is way too late.

Synthetic rigging may be the right choice for some folks, but just like with SS wire, all of it's pros & cons need to be taken into account.

Mark

Ehrm... agree. Yes, I think 80% will be exposed, if not more. So that means that at 10 years old it should be at 50% of it's strength and every bit it is stronger is due to the UV protective coating. I may test that with my runners.

I think the protective coating is a bigger factor than people believe. It should have a significant impact on fiber longevity.