Netting on Amsteel lifelines?

[matt the rigger]

First, I don't why any one would want to use ANY rope for life lines. there are a number of reasons NOT to use fiber life lines. Even in the one design classes that allow them,most have gone back to 1x19 wire. The fiber life lines require CONSTANT monitoring,and maintenance.The worst place for chafe is at the stanchions,and will require extra chafe protection. I've used the braided DYNEEMA anti chafe cover at the those points to help reduce chafe. It only holds out for so long,then needs to be replaced.So I guess I would use the same type of line for the webbing. If you spliced it in to the life lines there would not be any chafe issues.Chafe at those spots will not be a concern compared to the stanchions. I did not mention the U.V. issues,or the huge cost difference with fiber life lines.

[Brion Toss]

Hi Matt,
I respectfully disagree. While it is true that fiber lifelines can chafe at stanchions, this is a matter of sharp stanchions; reduce the edges, and the chafe goes away. Otherwise, the logic would dictate that you also dispense with rope halyards if the sheaves had sharp edges, instead of fixing those sheaves.
Note too that wire lifelines, at least covered ones, often fail at sharp-edged stanchions, because of corrosion that starts where the cover has been chafed away. We have Spectra lifelines all over the world now, with no problems, once chafe spots have been eliminated.
UV is a non-issue, partly because it slows down dramatically as the surface fibers oxidize, partly because proper-size HM lifelines are so overwhelmingly overbuilt. Wire lifelines, on the other hand, fatigue and corrode, and do so much faster in warm, salty climates.
As for the "huge cost differences", wha'? Wire coated to 1/4" is about the same as 1/4" Spectra, once you figure terminals in, and less if you dispense with turnbuckles. We use round bronze sail thimbles for ours, and lash them with Spiderline. Now, if you go with 1/8" "cheese slicer" uncoated wire, you can save some money, but heaven help you if you ever land on those things. Fatter wire, scaled to reduce bruising, is still not pleasant to land on. And the price goes up.
Oh, and by the way, constant monitoring of any lifeline is not a bad thing; the difference with rope is that you can actually see when it is getting dangerous. Wire, on the other hand, is inherently secretive about its condition, which is why sudden failures are so common with it.
For the above reasons, we simply won't install wire lifelines any more. On the other hand, rope lifelines require more from the installer -- you have to make sure there are no chafe points, that the splices and lashings are good, that all constructional stretch is out. Wire you can just bang out and move on. Not a compelling argument for me.
Fair leads,
Brion Toss

PS,
Getting back to the original question, I'd use smaller Spectra, or perhaps that Spiderline, for the netting. A couple of turns at the lifeline, to spread the load and prevent motion, will prevent any chance of chafe.

[JohnV]

Matt and Brion--
Thank you both for a thorough discussion of the pros and cons of fiber lifelines, and for your answers to my question.
Using dyneema will save on the cost of terminal fittings because I can ring-hitch one end and lash the other.
My stanchions have 7/16" holes, and the holes are lined with flared tubing. I plan to polish them, for peace of mind, with a strip of very fine emery fitted through a slot in a dowel and spun in a drill.
John V.

[Stumble]

John,

Your plan sounds eminatly reasonable to me. Though to be honest when I switched to rope lifelines three years ago I didn't do a thing to the stantions, no sanding, smoothing, ect...

Looking at the line now, it still looks brand new, and the only problem I have had was when someone fell against the lifelines and they did exacally what they are supposed to, in keeping him on-board. Luckily he was unhurt, though the line was so strong it snapped 2 out of 3 bow pulpit legs. Note that I consider this the desired behavior.

[JohnV]

Thanks for the reply, Stumble.
I'm going to go over the stanchions real well just in case, but I may be over doing it.
JV

[matt the rigger]

Brion,

I do see your point on cleaning up the stanchions in order to prevent the chafe.That's a given. I also understand your concern with coated life lines,and the necessity to inspect all life lines. I still do not agree that fiber material is the best material for life lines. I guess time will tell.

[blahman]

Brion,

On that note, where are you able to source bronze round thimbles? I've only been able to locate brass thimbles.

Thanks!
Aaron