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Larry Jaques[_4_] Larry Jaques[_4_] is offline
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Default Lamp Repair using a Rigger's Constricting Knot

On Wed, 9 Dec 2015 14:35:04 -0600, "SnA Higgins"
wrote:


"Joseph Gwinn" wrote in message
ws.com...
On Dec 8, 2015, Joe Gwinn wrote
(in article ):

Yesterday, I noticed that the lamp hanging over the kitchen sink was no
longer hanging by the woven polyester cable sheath (which is intended
to carry the weight of the lamp fixture) and was now hanging by the
electrical wires. Which were coming undone - the terminal screws had
already backed out a bit. Not good.

It turned out that over the five years since installation, the cable
sheath had wiggled out of the crimped strain relief ring ferrule at the
lamp end of the cable. The ring was crimped by being crushed into a
(US) football shape, and one end had broken, reducing the clamping
pressure on the cable. Discarded the ferrule. But what to replace it
with?

In the thread on corrosion when aluminum and stainless steel are in
contact, I had mentioned the Rigger's Apprentice book, and their
recipes for lanolin as a corrosion preventer.

This same book talks of "constrictor knots", used to repair such things
as split tillers. Hmm. This could work.

So, I replaced the metal ferrule with a double constrictor knot made of
nylon cord, all well daubed with Pliobond rubber cement. We'll see how
well this works, but it ought to be permanent.

Joe Gwinn


Ref: "The Complete Rigger's Apprentice - Tools and Techniques for
Modern and Traditional Rigging", Brion Toss, International Marine,
Camden, Maine, 1998 McGraw-Hill.


Followup: It failed already - the constrictor knot just slid off the
cable.
Probably due to the heat of the lamp softening things. I'll probably make
some kind of tight-fitting swage collar of metal.

Joe Gwinn


Yeah. I used know a Rigger like that. I think his first name was Jury.


He had another brother, Jerry, who used to MacGuyver things in der
Deutchland back in WWII.


Sorry. Couldn't resist.


Ditto.

--
Creativity can solve almost any problem. The creative act,
the defeat of habit by originality, overcomes everything.
-- George Lois