Guy rope choice

[prasadbodas2000]

I noticed very early rusting of GI wireropes (6mm which I had installed on a 2" NB pipe tower for a small 4 ft dia winmill) hence I have replaced the wireropes with nylon/hdpe like ropes. These are 12-13 mm dia ropes made from synthetic fibres and typically used by fishermen for the nets. This is not really clear nylon but some composite pvc/hdpe fibers. They have been up in sun and rain since march2011 and seem to be still in good condition. They do not elongate due to heat of sun which is otherwise typical to nylon fibre. I request opinions from all the board members please. I will try to post some picture but may be in a day or two.
With thanks and best regards,
Prasad

[Watt]

Have you noticed any more or less swaying from rope stretch since going to this synthetic rope?

[fabricator]

A long length of that type of rope is pretty elastic, I would be concerned about stretch in high winds, and also whether the rope has any protection against UV.

[Boss]

Here in the Southwest (US) we're ultra-envious of anything that causes rust. I woke last night due to the smoke from the forest fire above Santa Fe, gagging and choking. It used to be so nice living in the the mountains, now we have air pollution rivalling the big cities.
Anyway, I'd go with stainless steel cable if rust bothers you. Let me see if I can find the link to the rigging place we used:  http://webriggingsupply.com/ We don't have an affiliation with these folks, the cable is working great, thinnest for the strength, that sort of thing.
I'm a rural WiFi installer, spend a great deal of time on 70 foot towers, I've seen most every type of plastic break down in the sun, and way too quick. Even plastic that is supposed to be UV (outdoor) rated, lasts about a year in the sun down here.

[madlabs]

I'd say no plastic guys for me. It could be hard to tell when they are getting ready to let go too. At least rust is an inidicator.

[None54]

   I have to agree with Madlabs, no plastic rope for me...thats inviteing a failure in my openion.  Normal wire rope can be seal coated, or simply oiled to prevent or atleast retard rust, and will last years and years. I have coated wire rope with a high temp greese on my drag line, alittle greese goes along way at keeping the cable looking new and in good shape. Just put some greese on an old rag and wipe down the cable, you'll be done in a jiffy and usually one application last all year.

...None54

[prasadbodas2000]

@Watt & Fabricator - I did not see any noticeable stretch / elongation in the rope not even with wind load and also not over time. This thing had been into use since March 2011 and has seen the hottest sun of April and May. Being a coastal site temperatures however do not go above 35-36 deg C.

Thank you all for your responses, most of them not preferring non-metalic rope options. Below are a few pictures about the installation.

IMG_2357_WireRopeCondition.jpg	Rope attached to winch and other rolled rope are both purchased 3 years ago. Winch has been indoors as it is sitting in the picture. Rolled rope was attached to the mill and for about 18 months was in air. It was painted with red oxide primer on the fresh GI surface, but seems to be no use. The ropes have lost the springyness in the sense that unlike a new rope these used once get folded permanently if tried to turn them in coil of say 1 ft diameter (for ease of stacking). Perhaps the inner fibre/elastic like core material (I am told there is one strand of some such material) has lost all its properties?
IMG_2359_OverallInstallation.jpg	This picture shows the overall installation with non-metalic ropes.
IMG_2361_RopeAttachedtoWall.jpg	Picture showing attachment of the non-metalic rope to the parapet wall.
IMG_2362_SeaFacing.jpg	This shows how close my site is to the sea and obvious rusting due to very moist / humid air round the year.
IMG_2365_LiftingPole.jpg	Shows lifting pole arrangement, I opted to leave it in place.
IMG_2377_TowerBaseHinge1.jpg	View that shows the tower base hinge made out of plates and a pipe sleeve.
IMG_2378_TowerBaseHinge2.jpg	Another view of tower base hinge.
IMG_2381_LED_Lights.jpg	These small LED lights (3.6 V 15 mA, 56 in number wired as 14 parallel strands of 4 each in series with an overall one unit LM317 current limiter chip) just before the rectified DC from the mill getting into a battery. So these start glowing as the wind speed catches and their brightness increase untill cut in occurs. Once at cutin the brightness remains almost constant becuase the mill starts putting the current in battery and voltage almost remains constant.
IMG_2382_RectifierSet.jpg	3 Phase rectifier set (not visible since it is cast in resin)

Edited by DamonHD to insert images

[Bruce S]

prasadbodas2000;
 Those are nice pics, could you bring them down to 640x480 and less than 100k for us?
The dial up people have limits
Also If you would like them to show up on the post make sure ad select insert for each one.
You  will not see them in preview mode but once posted they will show.

Thanks
Bruce S

[prasadbodas2000]

@Bruce - I loaded the images with the limit of 150 K each. Also as you said, I wanted to have them embedded in the post.
Now that I can resize them below 100K and want them to have embedded, is it ok to post it once more or is there a way to edit my original post itself.
My apologies if there is a set of instructions about this somewhere on the board which I may have missed.

[DamonHD]

Hi,

I inserted the images for you: I hope I got them right!

Rgds

Damon

[prasadbodas2000]

Damon - Thanks a lot for making the post more readable.

With best regards,
Prasad

[fabricator]

Yikes! IMHO you are in for almost certain disaster with those polymer ropes, one thing you should also know is a knot reduces the strength of a rope by 50%, if you are in this for the long run I would bite the bullet and buy stainless cable, especially with just one set of guys, if you lose one rope it's game over.
As was stated before it's very hard to tell when polymer materials have been affected by UV or general environmental conditions, if you decide to stay with them, good luck.

[halfcrazy]

We use non metallic guy wires all the time in the radio world. We call it silly strand I don't know the trade name we also use big grips on the end or Pre Forms.

[DanG]

Cable stiffness is the braided strands being corrosion welded together in the core of the cable, not a good thing.

It would not surprise me if new steel cable is fabricated using a soy-based oil or some other health & safety promoted lubricant that will only keep the cable free of rust sitting on a shelf in a storehouse BUT defeats any penetration by average or traditional primer paints. Unless its a hot-dipped galvanized wire rope, steel cables are meant to live and work jacketed by gnarly grease that gets driven into the core when the cable flexes guided through sheaves and onto the spool.

In a fierce sun and salt climate seen in the pictures a marine stainless (316 SS: low-carbon 18~% chromium-nickel stainless steel modified by the addition of molybdenum) but beware the salts will act on items like SS clamp nuts & bolts, pitting the close meshed surfaces where the brines collect so better fasteners would be a high-strength bronze nut/bolt used on SS hardware allowing repeated re-tightening or disassembly without and damage from soft SS spalling or pitting etc.

If you want to go with SS cable but have to budget to afford it, maybe a couple of coats of a white water based paint on the poly rope & knots will be insurance against UV damage - titanium dioxide is a UV absorber so can protect plastics fairly well. The rope is pre-stretched now so the paint wont immediately be compromised  too.

Silly Strand? How about Philly Stran

http://www.phillystran.com/rope-products-fiber.htm

[bj]

Prasad:  I'm no expert, but I wouldn't trust the synthetics either.  You could however, make a deterioration gauge on your gin pole.
Piece of your rope, attached to the gin pole on one end.  The other end to a hefty spring.  (car hood spring comes to mind).
Stretch it to about half the spring, and secure.  Mark the end of the rope/spring with something that will last.  It will be in the same
elements/sun as your guys.  If you start to see stretch in the gauge,   time to do something about the guys.
On steel cables, I have good luck with the spray on chain lube that the dirt bike folks use.  Penetrates, and when the solvent flashes off,
it sticks like cat poo to a blanket.
May or may not be of help.

[prasadbodas2000]

I am really thankful and happy to see so many sincere and serious responses.
Threat to SS due to humid and sea weather as highlighted by DanG is what I have seen happening at site on the hinges and bolts for the doors of the house, and also budget is a valid reason. Perhaps brass and aluminium can escape the illeffects of weather by way of a protective oxide coating, but these materials are costly also like SS and not really suitable for wire-ropes (is that correct?).

DanG's suggestion to paint the fibre-ropes is a simple but great idea and I will follow the same.
I will also see if the rope material passes the test mentioned by BJ. Instead of a spring however I plan to use a dead weight.

Thanks all for the brainstorming and inputs poured in.

With best regards,
Prasad