securing wire rope at right angles

[njl]

Thanks Ian.

Most square lashing diagrams I see use a clove hitch for beginning and end. I'm concerned that a clove hitch wouldn't hold well in the single strand wire "small stuff". That's why I was thinking a Clamptite version might work better since it ends with the beginning bight and two ends of wire locked together. How would you start and end a square lashing using single strand wire?

The application is for an architectural model project I'm working on. In the component I'm designing, two lengths of wire rope are secured to each other at their center. This 90 degree connection slides into a cross shaped slot cut into the end of a spar. The spar is stepped like a mast and the four lines are tensioned like shrouds to position the spar in the air.

Non-slipping is important and a lashing would be better since it would have a lower profile and preserve wire strength. On the other hand the cross clamp would allow easier adjustment while I iron everything out.

[Ian McColgin]

Yeah, a clove hitch is out for any wire siezing. Take a look in "The Rigger's Apprentice" or any other good sourse for how to start and end a wire siezing. Then practice a bit as there's a knack.

[Ian McColgin]

Interesting application. I take it the rig is very low tension so you don't have to worry about splitting the spar and for some reason you don't want simple tangs over the top.

G'luck

[Brion Toss]

Hi,
You might want to serve the wires before seizing or clamping, in order to limit slip under load. As for the knot substitute when using wire, simply start with a long end, wrapped a couple of times around one wire, and trap that end under subsequent turns.
Having said that, I think you'll be able to generate at least as much friction and tension, with less flailing, if you use nylon twine over service. You can heave it tight, add layers, and frap it far more readily.
Fair leads,
Brion Toss

[njl]

Thanks Brion for explaining the beginning of the lashing. Regarding using nylon over service, in what circumstance would you opt for wire over synthetic seizing line (nylon or another stronger material like dyneema)?

Ian, I believe the tension will not be high enough to split the spar, but I may reinforce the spar end to play it safe. I'm avoiding tangs to allow easy knockdown and minimize components.

There's another thing I've wondered for a while since we're on the topic of seizings and service. If you parcel/serve/slush SS wire, is there an issue with oxygen starvation?

Thanks again for all the advice.

[njl]

I'm still hoping someone might be able to answer these two questions:

1. If synthetic seizing line is easier to work with than seizing wire, and considering the strength of dyneema seizing line, when/why would a person opt for using wire seizings for wire rope?

2. Hypothetically, if you parcel/serve/slush a section of stainless steel wire, is there an issue with oxygen starvation?

[Brion Toss]

Hi again,
Apologies for being slow in responding.
For the first question, seizing wire is tougher than twine -- more chafe- and UV-resistant in particular. You can slush the twine to prevent UV, and/or schedule replacement of lashings for the long term. For your application, I think it would be much easier to achieve appropriate tension with the twine than with wire. And I think I'd rather use nylon or Dacron, as both are quite strong enough, and much less slick than Dyneema.
Wire seizings for standing rigging are a bit more difficult to do than with twine, and though I have seen twine used instead, I've never seen destruction tests for them, nor am I confident about using something so relatively vulnerable for standing rigging terminations.
As for oxygen starvation, if you can keep out both air and water, it won't happen. My field experience with old served splices in stainless, over spreader ends, and under other short pieces of service, is that the water doesn't usually stay in place long enough for crevice corrosion to occur. But I have seen damage under longer stretches of served stainless, where the water was in far enough to be trapped. It couldn't evaporate or drain out -- or be rinsed out, in the case of salt water -- and it went to work on the wire. I always put some kind of slush on the bare wire, to limit surface area for water to work on, but I have seen old Concordia splices, unslushed, that were fine.
Fair leads,
Brion Toss