Ladder life

[Sally-J]

I had assumed that you continued using ladders until they looked like they might break ... then you stopped using them. Simple. But apparently the galvanising on galvanised steel wire ladders can come off and then the wires rust inside (i.e. not visible) over time and are then prone to breaking. That's my understanding of it anyway.

Given this, I am wondering how long galvanised (opposed to stainless steel) ladders can be used for. Obviously this would be to some degree dependent on usage.

Has anyone heard of this potential hazard or has any idea about how long they can be used for safely?

 

[Peter Burgess]

It's very easy to check if there is rust happening to a galvanised wire. If you untwist the wire a fraction you can see it. And I suspect a small bit of rust developing will very quickly show outside the wire anyway - the oxide colour leaches out quickly. Do you know how galvanising works? I have a ladder bought in 1980, and it is still in good condition. Keep it dry and clean and you should have no problems for many years.

 

[Sally-J]

Thanks.

The impression I got from the explanation I received was that it was impossible to tell if they were rusting inside, so I then concluded that it meant in the very centre where you can't get to .... but maybe you can.

p.s. I know galvanising is coating it in zinc which then reacts and prevents corrosion occuring. Not a very detailed understanding I admit.

 

[Peter Burgess]

Iron can only really oxidise where it is contact with the air, so that means on the surface. If you have to untwist the wire to see the surface, then perhaps this is what some understand as 'inside'. Also, galvanising will last a lot longer if it isn't kept wet. Look how corrugated iron sheets fall to bits where they are kept outside in the rain, and how they last for decades if under cover. Don't store ladders wet! Once the galvanising (zinc) has oxidised away, then the iron will very quickly follow.

 

[Sally-J]

So maybe my question should have been "How long does galvanising last when in contact with water?". Then I can do some maths on how often the ladders have been left muddy (and thus wet) or left in tackle bags, not by myself I hasten to point out  :ang: . This, over the years, could add up to weeks potentially. So maybe there is a risk ... if tackle is treated badly.

 

[Peter Burgess]

A long time ago now, some ladders were left in place in a cave during an expedition in Spain.  I can't remember the details, but although they were new ladders, they failed, or showed extreme signs of corrosion. I think this was put down to being placed in flowing water which may have been slightly acidic, in which case the zinc would have been removed very quickly, and this would have exposed the steel to the elements.

 

[Peter Burgess]

So maybe my question should have been "How long does galvanising last when in contact with water?". Then I can do some maths on how often the ladders have been left muddy (and thus wet) or left in tackle bags, not by myself I hasten to point out   :ang: . This, over the years, could add up to weeks potentially. So maybe there is a risk ... if tackle is treated badly.

I don't think any model you might think of is going to be at all reliable. There are too many factors to consider.

The quality of the galvanising.
The degree of abrasion the ladders are subjected to.
The acidity of the water
The temperature the ladders are kept at.
How dirty the ladders are.

Corrosion is connected to ion exchange, and the degree of ion exchange is governed by lots of things. For example, when water fills a microscopic crevice such as you get in a steel cable, the dissolved oxygen in the water will become depleted as it oxidises the metal it is in contact with. You then end up with a dissolved oxygen gradient in the water between the steel and the open air, and all these factors can potentially interact to create a very complex inter-relationship. It would be far easier to come up with a model based on a series of tests than to try to predict ladder life from theory.

 

[anfieldman]

Given this, I am wondering how long galvanised (opposed to stainless steel) ladders can be used for.

Can I throw another one at you Peter?
How long can stainless steel ladders be used for then?  :-\ Do you think they would be worth buying instead of galvanised ones?  :-\

Mark

 

[Peter Burgess]

Pass.

 

[Peter Burgess]

Actually, based on my own experience with a ladder bought for little more than ?1 per foot, (reflection of its age rather than  how cheap it was), if you look after a galvanised ladder properly, why bother buying something more expensive?

 

[shotlighter]

Actually, based on my own experience with a ladder bought for little more than ?1 per foot, (reflection of its age rather than  how cheap it was), if you look after a galvanised ladder properly, why bother buying something more expensive?

You were robbed, I've got one I bought in 1986 that was only 72p per foot. Mind you it was in Jo Royals sale!

 

[Peter Burgess]

Bought from a supplier who shares my initials.

 

[Sally-J]

Given this, I am wondering how long galvanised (opposed to stainless steel) ladders can be used for.

Can I throw another one at you Peter?
How long can stainless steel ladders be used for then?  :-\ Do you think they would be worth buying instead of galvanised ones?  :-\

Mark

We had planned to buy stainless steel ones ... until we saw the price. I think stainless steel ones could be good for (very rich) clubs as in that situation there is the risk people will not treat things properly. Galvanised ones do seem to last a very long time if treated ok, I'm just aware that they are not invincible (especially if left wet too many times).

 

[Peter Burgess]

Given this, I am wondering how long galvanised (opposed to stainless steel) ladders can be used for.

Can I throw another one at you Peter?
How long can stainless steel ladders be used for then?  :-\ Do you think they would be worth buying instead of galvanised ones?  :-\

Mark

We had planned to buy stainless steel ones ... until we saw the price. I think stainless steel ones could be good for (very rich) clubs as in that situation there is the risk people will not treat things properly. Galvanised ones do seem to last a very long time if treated ok, I'm just aware that they are not invincible (especially if left wet too many times).

You could be right. We replaced a few of our club ladders a few years back with galvanised ones that a CRO were chucking out. They were in excellent condition, but having seen how their predecessors had rusted, we know that regular checks and keeping them dry is the best way to look after them.

 

[shotlighter]

Seem to recall that the recomended storage method was to soak 'em in lanolin diluted in parafin (or similar). Must have made them very "interesting" to climb.
I've always used WD40, seems to work fine.

 

[caving_fox]

anfieldman:How long can stainless steel ladders be used for then?

Pretty much indefinately, if not used. They won't be effected by water, and even battery acid should have little effect if cleaned up promptly - what grade of stainless are they made of? different stainless steels do have different corrosion properties. SS is also more wear resistant than galvanised steel, but will eventually get worn through.

However they can be 10% heavier so get someone else to carry them!

 

[Bob Mehew]

Seem to recall that the recomended storage method was to soak 'em in lanolin diluted in parafin (or similar). Must have made them very "interesting" to climb.
I've always used WD40, seems to work fine.

Most wire ropes are made on a former; often this former used to be nothing more than a piece of string down the centre.  So untwisting a wire may just show you the dirty string, rather than rust.  I understood from way back when, that the soaking in lanolin was in part to reduce the ability of this rope to take up and retain water, thus reducing the potential for rusting from the inside out, but I may be wrong.  As for impacting on climbing after soaking, can't recall any problems; but ones' hands were soft and smooth after doing the soaking bit!

 

[Jopo]

Stainless ladders may not always last forever.  Many moons ago We made a ladder to replace the maypole at Maypole Inlet OFDll Streamway. It was constructed from 316 stainless wire, 6mm I think, and nimonic rungs, (a nickle chrome alloy as opposed to a iron chrome alloy), rungs, stainless pin and araldite construction. They lasted about 6 weeks before embrittlment caused the wires to start breaking next to the rung. A salutatory lesson in dissimilar metals which we have not forgotten.
Interestingly the steel ladder still in place there was made from heavy gauge 1" gas pipe with stainless welds, (a load of them had been liberated from Mond Nickle and they weld beautifully), and has been in use for approaching 30 years, at least 20 of which was directly in the stream. As a fixed aid they are inspected regularly and are in good nick. So far.

Jopo

 

[graham]

Most wire ropes are made on a former; often this former used to be nothing more than a piece of string down the centre.  So untwisting a wire may just show you the dirty string, rather than rust.  I understood from way back when, that the soaking in lanolin was in part to reduce the ability of this rope to take up and retain water, thus reducing the potential for rusting from the inside out, but I may be wrong.  As for impacting on climbing after soaking, can't recall any problems; but ones' hands were soft and smooth after doing the soaking bit!

We once bought a load of hemp-cored wire by mistake & spent a happy time soaking it in lanolin. The ladders were fine though we didn't use 'em for as long as those with steel-cored wires. What I don't recall is whether the wire was more or less prone to kinking than the normal stuff. More, I think.

 

[nickwilliams]

Jopo,

Was the embrittlement a function of work hardening of the 316 or some form of interaction with the rung material?

I've thought about using s/s ladders in digs (where the ladders tend to get left in the cave for months on end) but if work hardening is a problem, then that puts a rather different perspective on it.

Nick.