Rope bridge, finally. Now what knot?

[John@TreeXP]

I can confirm that the Safeguard will work with 11mm - 12.5mm diameter ropes!

That's wrong and misleading. Maybe your results are different and I presume you are not personally liable for improper use by others, due to your misrepresentations. Maybe you might want to include a warning label or a disclaimer with your comments, but how can you argue or defend against the actual manufacturer's guidelines, as advertised online at: https://madrock.com/products/safeguard ?

"Springless Lifeguard

By constructing the Lifeguard without the internal spring, the Safeguard is a great tool for rescue and rigging work. It will lock onto the rope with very little force giving you the confidence that once the position of the rope is set the device will not creep or slide.

For rescue / rigging use: 8.1mm to 11mm rope diameter

For climbing use: 8.9mm to 11mm rope diameter

Hot Forged Aluminum and Stainless Steel construction

Individually tested

Weight: 154g"

 

[agent_smith]

That's wrong and misleading. Maybe your results are different and I presume you are not personally liable for improper use by others, due to your misrepresentations. Maybe you might want to include a warning label or a disclaimer with your comments, but how can you argue or defend against the actual manufacturer's guidelines, as advertised online at: https://madrock.com/products/safeguard ?

I am happy to standby my assertion that you can use 12.5mm rope in a Safeguard - despite what the manufacturer claims.
(within the context of a harness rope bridge)

I thought you might try to play this card - and I encounter this line of thinking all the time.
Manufacturers always err on the side of caution - and give the usual warnings about their products. They are advised by lawyers to do so.

Using 12.5mm rope in a Safeguard does not result in death.

Many people also use 8.0mm cord in their Safeguard.

It comes under the general principle of 'fitness for its intended purpose'.

I would be more than pleased to debate the law and legal principles with you on this subject.

Another example is lead climbers who weigh more than 80kg.
EN892 dynamic ropes are only tested to 80kg maximum.
What if you weigh more than 80kg? Does this mean you void the rope warranty and/or you will be legally liable for any injuries incurred? Think about that one for a moment.

 

[Joeybagodonuts]

The Safeguard, without the spring works like the Grigri and it closes automatically whenever there's tension, as it should.

Like were all trying to explain, the "Safeguard without the spring" is NOT like the GriGri...The Grillon, yes, but GriGri, no.

The Grigri has a "negative" spring in there too purposely keep the cam open.. hence the reason it's "not suitable for us" & are advised to use the Grillon instead..

Again.. what am i missing here.. this is all basic 101 i never thought I'd have to hear individuals argue over.

 

[agent_smith]

Joeybagodonuts:
I agree with you 100%.
This fine fellow John@TreeXP has demonstrated consistently poor levels of understanding about the Safeguard device with its spring removed. He appears to be confusing this product with its sister - the 'Lifeguard'.
He also claimed that it was significantly larger than the Roll N Lock and about the same size as a GriGri (any iteration of GriGri). All of his claims are manifestly false.

The only fact stated from this fellow is the weight of the Safeguard - which is 154 grams.

He now also now wishes to engage in a legal debate with me about product liability and fitness for purpose.
I stand ready to engage in such a legal debate.
Fore warning on legal matters: I have studied law and have been called upon to provide expert witness testimony in matters pertaining to height safety and falls from height - including product liability. I frequently give legal advice to large corporations about height safety matters - and consult on safety at height issues (specializing in fall-arrest systems and fall-prevention systems).
I consult to OHS authorities and provide expert opinion in matters so that offenders can be successfully prosecuted.

I reaffirm and assert that using 12.5mm diameter rope in a Safeguard works fine - no issues - and death will not result. I have also used 12.5mm rope in a 11mm Petzl ID - no issues. I also weigh 100kg and frequently lead climb on rock using EN892 certified ropes (which are only batch tested to 80kg). I know many climbers who weigh more than 80kg and happily lead climb on their 80kg certified rope!

I would also comment that every-time a person uses hand tied knots at a workplace, he is doing something that can't be guaranteed and does not come with a engineering certificate. Same issue when using hand tied knots in trees as anchor points. I can confirm that a tree belongs to the vegetable kingdom and I have yet to see a vegetable that comes with an engineering certification and test tag.

I would further comment that most tree workers don't use a twin rope suspension system per ISO 22846 rope access requirements - preferring instead to use a single rope suspension system. Most PPE manufacturers advise that their products should be used with a back-up fall-arrest system (per ISO 22846 and/or AS 1891.4 if Australia).

I would add that a manufacturing label and user instructions are not law - that is - the PPE manufacturer is not representing the Parliament or Congress (if USA). Only Congress and State Governments can make laws in the USA (not product manufacturers). Manufacturers are obliged to provide vanilla flavor product warnings and standardized user instructions with all the PPE - because its necessary for CE compliance and/or ANSI conformance - so they can stamp these markings on their products and sell them (to make money).
There is no law to compel an end user to use PPE in the exact way specified. For example, most manufacturers of abseiling devices and/or guided type fall-arrest devices require a certain type of rope to be used with their product. Most specify rope conforming to EN1891 (A or B) and/or EN892. Sterling HTP rope is not EN1891 compliant - and yet, it is a perfectly fine rope.
Does this mean I will be sued and arrested if I use Sterling HTP rope in my PPE which specified EN1891 rope? Of course not.

 

[Brocky]

John says he has experienced the Safeguard having rope slip through it unexpectedly, have you had this happen to you, Agent Smith. Also any idea what the Sterling high strength cord is specifically, name or materials used?

 

[John@TreeXP]

Sorry, but I'm not buying into the idea that's it's ok to promote that people disregard a manufacturer's instructional guidelines and compromise personal safety on products they produce, test and assume liability for. That's utter lunacy, IMHO, and debating this issue only serves to further diminish your credibility. ... Mic drop.

 

[Jonny]

So how’s the Safeguard as a lanyard adjuster?
What country is it manufactured in?

Just making sure it’s clear, the Safeguard is the one without the spring on the cam, correct? Safeguard is kinda like Grillon, Lifeguard kinda like Grigri, yeah?

 

[John@TreeXP]

So how’s the Safeguard as a lanyard adjuster?
What country is it manufactured in?

Just making sure it’s clear, the Safeguard is the one without the spring on the cam, correct? Safeguard is kinda like Grillon, Lifeguard kinda like Grigri, yeah?

I think it's an ok option for a lanyard adjuster in a DdRT system, but like the Grigri, unless the device is loaded, rope will be able to slide/creep.

 

[agent_smith]

That's utter lunacy, IMHO, and debating this issue only serves to further diminish your credibility. ... Mic drop.

I'm sorry but the "Mic drop" is with regard to your level of knowledge (which, for this subject matter is alarmingly deficient).
It's a pointless exercise discussing this matter further - because you simply don't have sufficient depth and breadth of knowledge about the concepts discussed. Also, entering into a detailed and complex debate about legal issues will be a dead-end because you apparently can't comprehend the concept of fitness for its intended purpose ...eg as an adjustment device within a harness rope bridge (ie attached within a closed circuit system).

At the end of the day - follow your own protocols and I'll follow mine.

 

[DSMc]

No comment on my question regarding the two sides of a bridge a how much force is actually being transferred?

 

[agent_smith]

John says he has experienced the Safeguard having rope slip through it unexpectedly, have you had this happen to you, Agent Smith.

No - never.
However, I would comment that any gadget on planet Earth may - under a special set of circumstances - not perform precisely as expected. For example, ice build up, accidental contact with the lever, accidental pushing on the cam so that it is occluded, a twig or a small splinter caught up and blocking the cam, etc. However, even if this was to occur, and the cam failed to actuate instantly, you still won't die because the harness rope bridge is a closed circuit system.

Also any idea what the Sterling high strength cord is specifically, name or materials used?

Go to Sterling website for details about their cords and ropes.
Sterling are a reputable rope manufacturer in the USA.
I use a lot of different ropes and cords - and recently invested in 7/16 inch and half inch HTP ropes.

The concept of using the Safeguard within a closed circuit system such as a tree climbing harness rope bridge was mine - and one that I have found fit for its intended purpose.
Despite alarmist attitudes, you can use 12.5mm rope in the Safeguard if you wish.
I have done so routinely - and I appear to be still alive after more than a year of experimentation with different rope diameters.

I believe that I am alive because I am typing this post

 

[Brocky]

Yes, well aware of Sterling and their great products, I thought you were referring to a specific cord of theirs, and was wondering which one.

 

[agent_smith]

No comment on my question regarding the two sides of a bridge a how much force is actually being transferred?

Is this question is directed at me??
The actual force as measured by a load cell at each side termination of a harness rope bridge is dependent on the 'included angle' and the reference load.

Since you did not specify what the included angle is nor what the reference load at the focal point of the bridge is - it is impossible to answer your question.

However, for arguments sake, lets say that the included angle is 90 degrees.
And lets say that the load at the focal point is 100 kg (metric system).
If 90 degrees with 100 kg reference load, then each side termination would (in theory) be subjected to approximately 71 kg. Note that each side is a mirror of the other in a 50/50 shared system. That is, both sides sustain 71 kg.

If the included angle was 120 degrees - this is the critical angle - and results in 100 kg transfer to each side termination of the rope bridge.
Beyond 120 degrees, there would be load magnification - although due to inherent rope stretch, it would be hard to go beyond 150 degrees.

Now, I might ponder why you failed to provide a reference load and an included angle?
Maybe you just wanted me to pluck some numbers out of thin air?

In any case, load is shared equally between each side termination of the rope bridge (although hip rotation left/right would cause a bias to one side or the other). When the climber is relaxed, the system will tend to default to its central balance point.
As the included angle decreases, so does the transmitted force to each side termination.

 

[John@TreeXP]

Be advised, dangerous advice, abusive, condescending and/or patronizing remarks are subject to being reported to the site's administrator for further appropriate action.

 

[John@TreeXP]

John says he has experienced the Safeguard having rope slip through it unexpectedly, have you had this happen to you, Agent Smith. Also any idea what the Sterling high strength cord is specifically, name or materials used?

Just so I'm clear about this. The rope can move when the device isn't engaged/loaded on the non-springed SAFEGARD. Whether it slips or creeps accidentally, I can't say it's personally been a serious issue or a problem, because the device remains loaded whenever it's in use for the most part, but the fact that the rope can move remains a notable concern nonetheless. As far as using a Safeguard with ropes outside the prescribed parameters, as put forth in writing by the manufacturer, I'd encourage everyone to first check directly with the manufacturer before continuing and at that point if there are any new startling revelations, please share them with our group. Otherwise it appears like someone is giving bad advice with potential unforeseen consequences. If the device works on 12.5 mm ropes, in the manner the device was intended to perform, I seriously question why that's not included in the product documentation. Why would the manufacturer hold back something this profound? Going by one climber's personal experience isn't my idea of a sound approach in a case like this.

 

[DSMc]

... Since you did not specify what the included angle is nor what the reference load at the focal point of the bridge is - it is impossible to answer your question...

Yes, because there are variables at play, like force multipliers as the angles change and a harness bridge is never parallel to the load line when in use. So in your previous post below, how can each side of the bridge only experience 50% of the load?

... However, in the context of a rope bridge in a tree climbing harness, each side of the bridge only experiences 50% of the load...

 

[Brocky]

I would imagine the smaller the diameter rope running through it, the easier it would be for it to slip. A larger diameter rope would be more likely to be touching the cam to activate it. The tail would have to be above the device, easily possible in a tree, as probably any tail weight would force the rope against the cam. It might be possible for slippage if both ends were unloaded?
You may not like his delivery method, but I think Agent Smith is only giving what he has experienced with the Safeguard, not encouraging others to do likewise.

 

[John@TreeXP]

Because it's contrary to the mfg's recommended guidelines, my concern is about how well the Safeguard manages friction and dissipates heat, using a variety of larger diameter ropes that are able to fit, beyond the recommended diameters. The bigger the rope, the greater the friction, the hotter things can become. In Its current iteration the Safeguard is really only suited to work as a lanyard rope-grab substitute with possible slippage issues, IMHO, otherwise Wesspur and Tree Stuff would probably carry them, but they don't.

 

[climbstihl]

Because it's contrary to the mfg's recommended guidelines, my concern is about how well the Safeguard manages friction and dissipates heat, using a variety of larger diameter ropes that are able to fit, beyond the recommended diameters. The bigger the rope, the greater the friction, the hotter things can become. In Its current iteration the Safeguard is really only suited to work as a lanyard rope-grab substitute with possible slippage issues, IMHO, otherwise Wesspur and Tree Stuff would probably carry them, but they don't.

There won't be any issues with heat when using it for an adjustable bridge. Also, usually there is more heat with skinnier ropes, as there is not as much surface area to spread out the load and friction on. The issue you run into using larger diameter ropes is that you can't descend as easily and you can't take up slack well either. I wouldn't try ropes with smaller diameters than recommended without extensive testing though. I don't know why you think that it's only usable as a lanyard grab, it is perfectly useable as a primary descender as well, although it won't handle super long descents as well as an industrial descender or a grigri, just because it has a small cam. Devices with a negative spring (holding the cam open) are commonly used as primary multicenders, and are certified as such too, even when there is a springless alternative, similar to the safeguard. So even if the safeguard would allow slippage, which I don’t think it does, it is still perfectly useable.

 

[agent_smith]

Because it's contrary to the mfg's recommended guidelines, my concern is about how well the Safeguard manages friction and dissipates heat, using a variety of larger diameter ropes that are able to fit, beyond the recommended diameters.

Its actually becoming a non-sensical argument.
Look - with these types of remarks, clearly you are confused.
Within the context of a harness rope bridge, I am having extreme difficulty conceptualizing how a Safeguard device would ever suffer from over-heating.
In short - it is irrelevant.

Because it's contrary to the mfg's recommended guidelines

You keep bringing this matter up as a line of attack.
You are mistaken in this context.
I would be happy to go head-to-head in a technical legal debate with you in the context of manufacturers liability, product liability, workplace OHS laws and existing court cases where a tree climber was successfully prosecuted for using a 12.5mm diameter rope with a Safeguard device within a harness rope bridge.

Maybe here's a first challenge for you.
1. Find a successful prosecution at a workplace where a tree climber was cited, went to court and was convicted against an OHS law for using a rope diameter larger than 11.0mm in a harness rope bridge (with Safeguard). For example, 7/16 inch rope is actually 11.2mm. So this is 0.2mm beyond 11.0mm. Would a prosecution result from 0.2mm excess?
2. Provide evidence that using 12.5mm diameter rope in a Safeguard will result in catastrophic failure. Not just hearsay evidence (I'm not talking about hearsay evidence), I'm talking about experimentally proven evidence that will stand up to court scrutiny so it can be used to prosecute a climber.