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101RRS
28th October 2010, 12:35 PM
I have a spare 15,000lb winch that I intend to use as a portable winch mounted in a cradle that will fit into a tow bar receiver fitting.

With its 28m of wire rope the winch by itself weighs 50kg and probably with the cradle will be closer to 60kg - I can still lift it but it is a bit heavy.

I am thinking of replacing the wire rope with plasma to reduce the overall weight to make the setup a little more manageable. Also I find 28m of rope is not really long enough, particularly is a double pull is required so I am thinking of going down to 12,000lb rope to get a bit more on the winch.

There seems to be a lot of places to get rope - including ebay but I know very little about the stuff. So where would be the best place to buy plasma rope and how much would I expect to pay for say 40m of 12,000lb rope.

Oh what do people do with the old wire rope?

Thanks

Garry

KarlB
28th October 2010, 02:05 PM
This should get you started Garry: http://www.secondair.com.au/pix/pdf/dynamica_packsretail_prices.pdf

There is cheaper rope around but Dynamica is supposedly as good as the best ie it is made from Dyneema fibres (see here for a little more detail Dynamica Rope - Stronger than steel (http://www.secondair.com.au/dynamicarope/)).

Be mindful that for equivalent strength the plasma rope as a smaller diameter than the steeal, so you can fit more on the drum. Also, you need to replace any roller fairlead with a polished aluminium hawse .

Cheers
KarlB
:)

101RRS
28th October 2010, 02:40 PM
Thanks Karl.

Hmmm didn't realise the rope was so expensive. At those prices I think I might have to risk the hernia and stay with steel rope until something happens to it.

Cheers

Garry

KarlB
28th October 2010, 03:26 PM
You can buy it from here Dynamica winch rope (http://www.dnaoffroad.com.au/products.php?product=Dynamica-rope-off-the-roll-%5Bper-M%5D) for $1.05 per metre off the roll though it is not clear what diameter it is. You can find splicing information here http://www.dborc.co.uk/goodwinch/pdf/dyneema%20use.pdf . It would make it a lot cheaper if you made up the winch rope your self. Tubular sleeving would not be hard to get. You could probably use the existing hook.

What will it cost if you get a hernia?

Cheers
KarlB
:)

isuzutoo-eh
28th October 2010, 03:45 PM
Hi Karl,
If you select the diameter you want the price per metre changes too. 10mm dia is $15.50 per metre. Not so cheap compared to some on ebay it seems

KarlB
28th October 2010, 04:03 PM
I am as blind as a bat as well as a silly old fool! Thanks. You only end up saving about $50 then. Bugger all and not worth the effort. Still think it is cheaper than a hernia though.

Cheers
KarlB
;)

stig0000
28th October 2010, 05:51 PM
or jsut sell that winch and buy one with rope allready on it:D

Hoges
1st November 2010, 07:16 PM
I'd try Bullivants Bullivants Handbook (http://www.ebooks.geongroup.com/Bullivants/Handbook/Index.aspx)
they sell all sorts of lifting/handling equipment...the book above has a section on high performance ropes...may meet your needs at a reduced cost!
cheers

Owl
7th November 2010, 07:38 AM
I've purchased winchrope from these guys:
OKoffroad - 4x4 Recovery Gear - News 'N Views - 4x4 Accessories (http://www.okoffroad.com/)
Rope is Amsteel Blue. It is Dyneema fibre (UHMWPE) as above and 5/16" (8mm), 13,000+lb breaking strain is less than $200.00 for 100' rope made up with thimble, terminal, and protection sleeve. There's no excuse for using steel cable at these prices.
Service from them was excellent - I had my order (rope and fairlead) delivered to my door within the week of ordering.

Ian

Tank
8th November 2010, 11:54 AM
I've purchased winchrope from these guys:
OKoffroad - 4x4 Recovery Gear - News 'N Views - 4x4 Accessories (http://www.okoffroad.com/)
Rope is Amsteel Blue. It is Dyneema fibre (UHMWPE) as above and 5/16" (8mm), 13,000+lb breaking strain is less than $200.00 for 100' rope made up with thimble, terminal, and protection sleeve. There's no excuse for using steel cable at these prices.
Service from them was excellent - I had my order (rope and fairlead) delivered to my door within the week of ordering.

Ian
Did they (OKoffroad) give you the SWL (Safe Working Load), or WLL (Working Load Limit) of the 8mm rope that you purchased, i.e. 13000lb Breaking Strain (BS) divided by ? Safety Factor (SF) = WLL or SWL.
BS divided by SF = SWL
13000lb divided by 5= 2600lbs.
The SF of 5 used here is for General Purpose use for wire slings and most lifting gear, I am wondering what the SF is for this type of rope.
You know of course that you should never exceed the WLL and never work to the Breaking Strain of the rope. All winching/lifting gear deteriorates from it's first use and eventually fails Well below the BS, that's why SF are applied, Regards Frank.

Owl
8th November 2010, 12:29 PM
Did they (OKoffroad) give you the SWL (Safe Working Load), or WLL (Working Load Limit) of the 8mm rope that you purchased, i.e. 13000lb Breaking Strain (BS) divided by ? Safety Factor (SF) = WLL or SWL.
BS divided by SF = SWL
13000lb divided by 5= 2600lbs.
The SF of 5 used here is for General Purpose use for wire slings and most lifting gear, I am wondering what the SF is for this type of rope.
You know of course that you should never exceed the WLL and never work to the Breaking Strain of the rope. All winching/lifting gear deteriorates from it's first use and eventually fails Well below the BS, that's why SF are applied, Regards Frank.

It's breaking Strain. Breaking Strain of standard wire rope supplied on most 9000lb winches is only just over 10,000lb. Recovery winch specifications do not follow Australian Standard lifting regulations so you should not try to compare them.
Ian

Tank
8th November 2010, 09:44 PM
Ian, every winch for sale in Australia (for 4wders) shows the BS of the rope and advertise the winch at that capacity.
It doesn't make any difference whether the rope (wire cable and plasma) is used for lifting or drag winching, all ropes have a Guaranteed Breaking Strain (GBS) and if you work a cable or rope to it's GBS then you are courting disaster. Every time you use a winch rope you are degrading it's strength, that's why in the Rigging industry or any industry using cables there is a built in Safety Factor (SF).
A 10mm winch rope, which has 7 strands would have a GBS around 12000lbs with a SWL or WLL of 2400lbs.
Where do you get the figures for the GBS of a 9000lb winch rope lifting or dragging ability (Strength) is governed by wire/rope dia. and construction, I've seen 7 and 8mm ropes on a winch that was labelled 9000lb capacity.
You need to remember that the size and construction of the cable/rope on a winch determines the capacity, no winch should be rated at the GBS of the cable, it should be rated at the WLL or SWL of the rope/cable, same as rated shackles, Regards Frank.

Owl
10th November 2010, 04:36 AM
Ian, every winch for sale in Australia (for 4wders) shows the BS of the rope and advertise the winch at that capacity.
It doesn't make any difference whether the rope (wire cable and plasma) is used for lifting or drag winching, all ropes have a Guaranteed Breaking Strain (GBS) and if you work a cable or rope to it's GBS then you are courting disaster. Every time you use a winch rope you are degrading it's strength, that's why in the Rigging industry or any industry using cables there is a built in Safety Factor (SF).
A 10mm winch rope, which has 7 strands would have a GBS around 12000lbs with a SWL or WLL of 2400lbs.
Where do you get the figures for the GBS of a 9000lb winch rope lifting or dragging ability (Strength) is governed by wire/rope dia. and construction, I've seen 7 and 8mm ropes on a winch that was labelled 9000lb capacity.
You need to remember that the size and construction of the cable/rope on a winch determines the capacity, no winch should be rated at the GBS of the cable, it should be rated at the WLL or SWL of the rope/cable, same as rated shackles, Regards Frank.

Hi Frank,
You are absolutely correct - Winch cables should be rated with a SWL or WLL much higher than the rated capacity of the winch.

However ......

This is not the case. Most 9000lb winches sold for our 4WD recovery duties will have 7mm or 8mm wire rope supplied with the winch. Bullivants catalog suggests that these ropes have MBS (Minimum Breaking Strain) of ~8,300lbf and 10,600lbf respectively.

These cables barely match the advertised load expectation of the winch. If you're lucky, the cable won't break before the winch stalls.

I'd much rather have 13,000lb (~6,000Kgf) Breaking Strain synthetic rope on the front of my vehicle than the regularly supplied, significantly lower BS, significantly more dangerous when it does break, steel cable.

Ian

Tank
10th November 2010, 10:20 AM
Ian, winches are rated by the SWL or WLL of the cable or they are supposed to be, for instance if you spooled 7MM wire onto a winch drum on a crane with say a SWL of 25 tonne then the fact that the winch will certainly lift/pull 25 Tonne with it's correct cable, it is now reduced to only being able to lift/work to the limits of the 7mm rope and of course vice versa a 25 Tonne SWL cable would not increase a 9000lbs winch SWL, because it would be impossible to fit to the winch.
We have to get away from the GBS/MBS of a cable or rope mindset if you have the BS in your head when doing a recovery you will be expecting too much from your rope/cable. I am a retired rigger/mechanic and in the 20++ years of professional rigging I have never broken a cable, nor have I ever damged or broken any of my recovery gear over that same period. Yet every week there is a sad tale of people breaking cables/rope and they seem to think it's normal. If we work our recovery gear to it's SWL/WLL then there should not be a problem, think SWL/WLL not GBS/MBS, Regards Frank.

Owl
10th November 2010, 06:45 PM
I am a retired rigger/mechanic and in the 20++ years of professional rigging I have never broken a cable, .......
Regards Frank.

That's your problem Frank - I'm not saying it's a bad problem, and I had already deduced this from your previous posts! Your attitude to safety has to be commended.

However .....
If I were to put a winch on the front of my 4WD rated at 9000lb, and cable with a SF of say 5, I would need to spool it with 15mm dia wire rope weighing over 1Kg per meter, and I would have to spool it on a drum dia of 300mm.

The size alone would make it totally impractical on anything smaller than a Unimog, and then the winch wouldn't be man enough!

Unfortunately, we in the 4WD fraternity have to be content with recovery winches that have drums smaller than optimum and cables rated close to their BS. This is one of the reasons why all the training for winch recovery prepares us for the possibility (probability) of a broken cable - and another reason why it is much safer to have synthetic rope out there than steel.

The alternative is to re-rate all the winches on the average 4WD's out there to 2000 - 2500lb and not be able to recover anything much!

You'll have to learn to leave your riggers hat off, but don't throw it away - keep it in the glovebox!
Ian