Dynex Dux Synthetic Rigging

[beiland]

Just happened across this rather interesting discussion of some differences in coeff's of expansion between mast and rigging materials,...and other temperature related subjects/

Issues with synthetic rigging? - SparTalk

[Suijin]

FYI synthetic lifelines will no longer be allowed next year in the US Sailing Equip. Requirements (offshore racing safety requirements) after they were add not so long ago. Evidently reported failures have been numerous enough to cause concern, and the Naval Academy did some objective testing of them for their Navy 44s and deemed them unsuitable.

I don't have any more info on the testing, although a guy I know at Annapolis Rigging said that most of the issues have likely been the result of retrofitting synthetic lines into systems built for wire (e.g. stanchions).

I think for runners and the backstay I'd consider it, but nothing more on a cruising boat at this stage.

[jaybird1111]

Originally Posted by Suijin

FYI synthetic lifelines will no longer be allowed next year in the US Sailing Equip. Requirements

It should be noted, this does not apply to multihulls. Multihulls are indeed allowed to have synthetic lifelines

[w32honu]

Just became aware of some info recently........

Apparently the insurance industry initially recognized synthetic rigging for a life span of ten years. Then they altered their certification to five years. Now they have changed it once again........ Certified for ONE year.

Not sure how they arrived at this. Insurance companies definitely tend toward the statistical ......

We currently have Dux runners, topping lift, life lines, and back stay. Love the stuff. But I will keep a close eye on it. Our boat is solidly in the cruising monohull camp. Due to re rig soon. I am going to go with SS 1 X 19.


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[Aikiguy]

US Sailing is a horrible organization when it comes to making rules that make sense.... They evaluate on bad information and their own bias time and again.. What caused the failures? Where the failures caused by incorrect installation, incorrect maintenance? Incorrect selection of product A installed on Product B? You don't get to know any data out of the group ever. They are leading the charge to make sail boat racing (the only thing they care about or address) more expensive and out of range of the common people.

The insurance industry? Big group, I have not seen this in any of the rigs that I have installed, or surveyed being questioned by any insurance group ever. I'd have to see some information for a verifiable source instead of dock talk. Also Synthetic rigging is a wide number of products. There is some of it that is only rated for 1 year by the manufacture. (PBO). So that is like saying all cars must go in for a complete tire change every 20 miles or less (What they run in the Nascar races I am told). Dynex Dux is currently rated for 8 years which is very conservative. Current pull tests are less than 30% loss of strength in 10 years. (Remember Dux starts out 5 times the strength of the stainless steel it replaces).

Make sure that you 1 x 19 rigging comes from the right end of the block in Korea, where it is all manufactured lately. We have been seeing it last less than 3 years in the tropics with catastrophic failures happening when the center yarns parted!

Guy
:-)

[Stumble]

My insurance company didnt care when we switched to Dux rigging. In fact we got a discount for al new standing rigging. The only material I could see them rating at 1 year would be PBO but as far as I know PBO is pretty much dead. Anyone with the money to feed PBO rigging is switching to carbon anyway.

[w32honu]

I hear you guys loud and clear. I struggle with the quality of SS 1 X 19 these days as well. Can't tell you how many times I have waffled on this decision. One day I read about issues with Asian manufactured SS. The next is some issue with Dux.

The webinar I had watched was paneled with very experienced folks that would be consider reliable. But in fairness the comment was vague and simply mentioned "synthetic" rigging and not Dux specifically.


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[w32honu]

There is an update article written by Andy Schell about his yawl Arcturus. He rigged his boat with Dux a number of years ago and crossed the Atlantic.

www.sailmagazine.com/writer/1180

Most folks may have already read it. If not it is worth a read for the fact that he had John Franta pull test two shrouds after covering the miles. Apparently with acceptable results.

[w32honu]

For what its worth the comments mentioned about the short life of synthetic rigging came from a webinar posted on Wally Moran's (Sail Magazine) you tube channel. It is a long video of general cruising topics. Paneled by a fairly experienced group. Tania Aebi, Liza Copeland, Lin n Larry Pardey, and Amanda and John Neal from Mahina Expeditions………..among others.

www.youtube.com/watch?v=bSuxsfh-DmQ

I can't pretend to speak for them. The video is very long. Just forward to minute 59:55

Not meant to suggest that anyone or anything is right or wrong. Just info for the forum.

[Stumble]

I watched the video, but it doesn't really discuss Dux rigging. All he mentions is synthetic which would include PBO. There is no question that PBO is a very short term option and needs to be replaced very frequently, but Dux is a wholy different material. It isn't as high performance at the tradeoff in UV resistance.

I am not trying to beat a dead horse, but there are plenty of boats out there with Dux standing rigging that are goi on 4-5 years or more without an issue. Is it right for everyone? No probably not, but it does need to be investigated according to its actual properties, not hyper-critically because it falls within a class of materials that have issues.

If this 'synthetic' label is applied to both PBO and Dux the label 'metal' would also need to be applied equally to siliconized bronze and zinc thru hulls. Obviously SiBz and Zinc are radically different in how they react to being submerged. The same is true with Dyneema and other 'synthetics'.

[w32honu]

Originally Posted by Stumble

I watched the video, but it doesn't really discuss Dux rigging. All he mentions is synthetic which would include PBO. There is no question that PBO is a very short term option and needs to be replaced very frequently, but Dux is a wholy different material. It isn't as high performance at the tradeoff in UV resistance.

I am not trying to beat a dead horse, but there are plenty of boats out there with Dux standing rigging that are goi on 4-5 years or more without an issue. Is it right for everyone? No probably not, but it does need to be investigated according to its actual properties, not hyper-critically because it falls within a class of materials that have issues.

If this 'synthetic' label is applied to both PBO and Dux the label 'metal' would also need to be applied equally to siliconized bronze and zinc thru hulls. Obviously SiBz and Zinc are radically different in how they react to being submerged. The same is true with Dyneema and other 'synthetics'.

I agree 100%. The video is somewhat confusing because the question to the panel DOES specifically reference Dynex Dux. But the answer given DOES NOT. And it does (the answer) seem to lump together all "synthetic" rigging.

What might need clarification is …….does the insurance company recognize the difference or do they, or will they lump together all synthetic rigging?
Its a mute point for me. It might be better to self insure by way of tending to your own rig. But who knows what a particular insurance company might do when faced with a claim.

As far as I am aware Lloyd's recognizes Dux as a qualified material for standing rigging………………just not sure for how long??

[w32honu]

Stumble,

Can I ask you……………How long have you had your Dux rig?

Any issues at all?

Also, I am doing a comparison of cost. All new sta-locs and 9/32 wire…….verses…….a Dux rig (9 mm) with terminators. The same lengths …..etc. The cost difference is substantial. The Dux rig being more expensive. Labor is not included as a DIY.

Was that your experience as well?

Thanks

[Stumble]

Mine came new with the mast after out mast snapped in half. The five year old mast broke thanks to a poor extrusion and encapsulated bubbles in the aluminium.

When we ordered a new mast it came with Dux rigging instead of wire (the boat manufacturer switched to Dux as OEM materials). So we had a little problem making the change over, mostly with the chainplates being designed for turnbuckles and the rigging delivered assuming deadeyes. It was a pretty simple fix and just went to larger turnbuckles than the loads justify to get all the hardware to mesh properly.

Other than that no issues as all.

Right now the rigging is about two years old and lives on a mooring in Jamaica, so just about the worst UV exposure possible. It still looks new, no wear, no chaff anywhere, and last time I dropped the mast the area at the spreaders was indistinguishable from the rest of the rigging.

I do plan to change at five years even thought the conventional wisdom is 8-10. my feeling is that after you buy the fittings, which are all reusable, replacing the rope will only cost me a couple hundred dollars and I would rather be safe. But I doubt it will be justified mechanically.

[Opie91]

Originally Posted by Stumble

I do plan to change at five years even thought the conventional wisdom is 8-10. my feeling is that after you buy the fittings, which are all reusable, replacing the rope will only cost me a couple hundred dollars and I would rather be safe. But I doubt it will be justified mechanically.

Hard to argue with that logic. It cost less for the new line than to unstep the mast!

[Stumble]

It's on a 24' trimaran so unstepping the mast is actually pretty easy. But the boat only has about 60' of side stays. So I figure it will cost me about $150 to replace all the standing rigging. The fittings are all aluminium so as long as they aren't physicaly damaged reusing them isn't an issue.