On Sun, 24 Jul 2005 20:50:46 -0400, "Hal Rosser"
wrote:

Ropes:== I tried using normal white nylon line (But Painting it black).
the paint makes it stronger and uv-resistant. And lasts longer.

Some different thoughts on painted rope:

Synthetic fibre ropes are subject to UV attack, but they are also
often subject to chemical attack.

If your rope really is nylon (Polyamide), it is resistant to alkalis
but is sensitive to acid attack. It should not be painted with
anything that will be acidic, or create acidic products in
decomposition.

In most serious rigging applications, any synthetic fibre rope or
sling that was subject to chemical inundation (acid, alkali, solvents,
paints, fuel, oil, contaminated water etc) would be condemned.
Additionally, painting the exterior of a rope probably increases the
risk of rot and mildew internal to the rope.

Over here, a very low cost synthetic fibre laid three stand rope
called "Silver Rope" (flat spin taniklon fibre), white in colour, is
used for marine applications. Not only is it dirt cheap, but it seems
to last on small boat moorings for years. I have had 6mm halyards of
Silver Rope up for over 5 years and there is no significant
degradation. (I wouldn't paint it, it resists mild acids, but is
attacked by alkalis.) (Silver Rope is about the same strength as
natural fibre rope, and about 50% of that of nylon.)

My choice for a synthetic fibre rope for non-structural antenna
rigging would be Silver Rope. It is cheap, it holds knots and splices
well, it is resistant to mild acids (pollution by products), and seems
to give a reasonable service life in UV exposure.

Polypropylene is also resistant to mild acids (and alkalis), but it is
a slippery (greasy) rope that doesn't hold knots or splices as readily
as natural fibre ropes.

Owen
--

Owen wrote:
. . .
Polypropylene is also resistant to mild acids (and alkalis), but it is
a slippery (greasy) rope that doesn't hold knots or splices as readily
as natural fibre ropes.

Polypropylene deteriorates rapidly from the UV in sunlight. Here in
western Oregon it'll last a couple of years before seriously weakening,
but in Denver (mile high and lots of sun) it turns to little more than
powder in about six months.

Roy Lewallen, W7EL

I have used rayon for years .....in fact I put rayon between the posts that
held my grape vines ....went by the old QTH yesterday and the grapes were
still up after almost 20 years .....

73 all de Tom Popovic KI3R