CamJam XT tie-down

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Stretched out
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CamJam XT tie-down

Post by Stretched out »

Having being into climbing, the outdoors and SB for several years, I've tried used the two ring device, luggage cam straps, prusick loops and spliced whoopie slings and also a cheaper alternative of these as means to tighten a rope.

These CamJam caribiners are alloy with a good casting and finish. 280lb working limit and 837lb quoted breaking strength puts them way over the cheaper plastic versions which can be pulled apart.
With paracord and 5mm braided rope they have worked great with negligible slippage.
They specifically state they aren't for climbing and I'd add suspension onto that too as there's a chance you could pull the rope through at an angle and unknowingly have the rope only partly engaged in the cam... At 70kg I have stood in a loop and bounced up and down a bit and it was solid.

With no or little load on it, pulling sideways on the free end will pull the rope free from the cam. With some load on it, pulling sideways doesn't seem to free it.

The release catch is quite small, but seems to work with modest loads on it. If not, pulling on the free end unloads the cam enough to allow it to be released.

Edit. After 2 pages of argument over these not being *strong enough* to support a person, which I think was slightly missing the point of them not being safe enough.

For me at 70kg these would have a safety factor of 4:1. For me that would be *strong enough* if it could be guaranteed to work perfectly every time.
Yes it's not the 5:1 or 10:1 commercial safety factors, but hypothetically your only a short way above the ground and you'd be unlikely to rig yourself above something that you wouldn't want to land on.

Theres no rating for the gate being open. It would probably fail if you inadvertently knock it open, or it doesn't close correctly.

2mm to 5mm cordage isn't particularly strong and any damage or knots will weaken it substantially.

It's possible to partly engage the cord with the cam, which feels like it's locked off, but definitely isn't.


So that's why I think there's more to safety than stamped rated loads.


41pwg6RpfnL._AC_SY580_.jpg
https://www.amazon.co.uk/dp/B01KPANSJO
Last edited by Stretched out on 21 Feb 2021, 12:25, edited 3 times in total.
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Shannon SteelSlave
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Re: CamJam XT tie-down

Post by Shannon SteelSlave »

Most members here don't practice solo suspension, as falling is only 1 danger. The other danger is uneven load.
But as a pull and cinch method for self bondage, this could be quite useful.
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Stretched out
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Re: CamJam XT tie-down

Post by Stretched out »

Exactly.

Whilst they are more than likely strong enough to use in suspension, the 2mm to 5mm cords may not be. Especially when knots and other de-rating factors are considered. That's beside the possibility of pulling the cord out of the cam, takes them right out of the game.

As a pull to tighten device, they rock. Unless you're an international strong man competitor, there's not going to be many people capable of breaking that part of the tie. Even with just using regular 220 paracord.

Paracord is good, because it's plenty strong enough but relatively cheap and easy to cut with a pair of scissors when allowed.
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Re: CamJam XT tie-down

Post by Stretched out »

I've just found the crappy plastic ones, so posting this picture as to one's to avoid!
The cam is only held in place by the plastic spring along the back, so if you managed to get it to bite, the cam will pop out.
More likely it will just slip at anything more than 5kg
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davisev5225
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Re: CamJam XT tie-down

Post by davisev5225 »

Stretched out wrote:Whilst they are more than likely strong enough to use in suspension
NO THEY ARE NOT!

These are not rated, nor are they designed, for suspending a person. They are only rated for approximately 280lbs (127kg) load and a break strength of 827lbs (380kg). Also, that doesn't take into account the 10:1 safety factor you should have in any equipment that is meant to suspend a person. Given the average weight of an adult male being around 190lbs (86.2kg) and the average adult female being around 170lbs (77.1kg), you shouldn't be using anything that can hold less than 1900lbs (861.8kg).

(It's worth noting that these don't even have the industry-standard rating of 5:1 for overhead loads not involving a person. Not really something I'd trust with my weight.)

Also, given that people likely won't just passively "lay" in their suspension, you must take into account shock loads. There's a chart at the bottom of THIS PAGE that is useful reference.

DO NOT USE THESE FOR SUSPENSION PURPOSES! In fact, don't practice suspension at all unless you are trained and certified for climbing operations; and even then, it's not a good idea. Too many things go wrong in the best, most controlled circumstances, and self-bondage is hardly the best.
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Re: CamJam XT tie-down

Post by bound_jenny »

Amen to that! :D

And some hard facts to prove it.

Thank you, davisev5225! 8)

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Re: CamJam XT tie-down

Post by OrgasmAlley »

There are all manner of issues using something like this cam tensioner *alone* in suspension rigging, but that doesn't mean it's useless in such an application. You've got to view a suspension setup as a system of components, each of which must be rated sufficient to its task. For example, a rigging point, block and tackle, tensioner, and release. This would pair fine with Type IV milspec paracord (750lb breaking strength) as the tensioner, using a 4:1 block and tackle rated for say 3000 lbs. I would absolutely employ a separate method of release... and of course the implication of this kind of setup is that "release" actually means "fall." I've always preferred chain hoists, and in partnered play. Really just posting to note that there are solutions to things that aren't always obvious at first blush.
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Re: CamJam XT tie-down

Post by davisev5225 »

OrgasmAlley wrote:You've got to view a suspension setup as a system of components, each of which must be rated sufficient to its task.
Each component should individually rated for a minimum of 1900lbs capacity. These are not.
OrgasmAlley wrote:This would pair fine with Type IV milspec paracord (750lb breaking strength) as the tensioner, using a 4:1 block and tackle rated for say 3000 lbs.
The block and tackle would be good, the paracord would not (since the paracord is not rated for 1900lbs loads...)
OrgasmAlley wrote:Really just posting to note that there are solutions to things that aren't always obvious at first blush.
This is the danger of trying to "get creative" with solutions. You've posted a "solution" that fails to meet the necessary safety requirements for suspending a person. If you don't explicitly know what you're doing, please don't try and practice suspension. It's dangerous, possibly deadly, and not worth it. I'd say that if you have to stop and re-think whether something is safe, it probably isn't and over-analyzing it is going to lead to problems.



I provide these warnings, and am a bit harsh about it, because I am trained and I care. I've seen what happens when people get careless with their safety. Example: I personally knew a guy that was working in a bucket truck that got hit by a lorry - he was ejected like a catapult and ended up in the hospital with neck and spinal injuries - all because he made mistakes during his elevated work. I'll remind everyone that this was considered "the best" of circumstances - he was using rated equipment in the prescribed manner with a safety spotter on the ground and had all his limbs free. He still took an ambulance ride.

Please be safe in your endeavors.
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Re: CamJam XT tie-down

Post by Shannon SteelSlave »

I love the idea of being interrogated by being bound and every failure to comply is met with being raised higher and higher in a warehouse with a high ceiling. The adrenaline rush would be too much to concentrate on the questioning line. But I will never again attempt to simulate it. Falling 6 inches head first did it for me. I could have been paralyzed. It's hard enough to take a fall on purpose and land properly. Even harder when you can't move to land or brace the fall. Impossible when you are unable to move and are in an awkward position.
Even if you know what you are doing, you might still make a mistake, we all do when we're in that mood. I lose about 40% intelligence in play. That's why I count on planning ahead, following a plan, and never giving in to last minute ideas. Leaving a buckle loose, or not tensioned evenly can leave you dangling in an unsafe or unintended position or cut off circulation. Your timed release may not come soon enough to prevent serious problems that require hospitalization, and you can't get it, because you are left hanging.
Just my 2ct.
Bondage is like a foreign film without subtitles. Only through sharing and practice can we hope to understand.
A Jedi uses bondage for knowledge and defense, never for attack.
I am so smart! I am so smart! S-M-R-T!....I, I mean S-M-A-R-T!
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Re: CamJam XT tie-down

Post by Stretched out »

They specifically state they aren't for climbing and I'd add suspension onto that too as there's a chance you could pull the rope through at an angle and unknowingly have the rope only partly engaged in the cam
@Dave. You've gone off on a quest about the load rating, but that's irrelevant if the rope can slip sideways out of the locking mechanism. They aren't reliable enough to be considered as valuable load supports.

When correctly set they are unbreakably strong and work for easily tensioning a bondage position. Spread Eagle, hogtie, etc.

Each component should individually rated for a minimum of 1900lbs capacity. These are not.
Theres a big discord between commercial working at height rules and sports/hobbies.

I guess you've not been sport climbing, as there's lots of climbing protection that is only rated to 2 or 3KN (449 to 674lb). By the above point, anything below 8.5KN needs to be recalled immediately. Or maybe people would be sensible and use them as part of a system.

You've also never layed in a hammock! Or you don't class being slightly off the ground, suspended on a single layer of nylon as requiring the 1900lb load rating your fond of. The general rule is don't hang higher than your willing to fall
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Re: CamJam XT tie-down

Post by Shannon SteelSlave »

Mine limit is -6 inches, I guess. Wouldn't be a long interrogation.
Bondage is like a foreign film without subtitles. Only through sharing and practice can we hope to understand.
A Jedi uses bondage for knowledge and defense, never for attack.
I am so smart! I am so smart! S-M-R-T!....I, I mean S-M-A-R-T!
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Re: CamJam XT tie-down

Post by OrgasmAlley »

davisev5225 wrote:Each component should individually rated for a minimum of 1900lbs capacity. These are not.
Can you provide any mechanical engineering standard or similar reference that ignores multiple legs in load calculations as you're proposing here? AMSE certainly doesn't. I am happy to proven wrong by a citation from any such body but I cannot imagine it.

First, clearly two identical ropes holding an evenly distributed load have twice the load rating of one of those ropes acting alone, in the same way two people can lift more than either can solo. Likewise, a block and tackle (the ultimate even distribution of load) is rated at rope strength * number of legs between block and tackle, and requires a free-end force of load / number of legs. Lifting a 400 pound load with a 4-leg B&T requires 100 pounds force and loads each strand to 100 pounds... not 400 pounds. Note that if we assume the vertical downward application of the lifting force, this also reduces the load at the lift point from 800 pounds for a simple rope and pulley (400 pounds of load, 400 pounds of lifting force) to 500 pounds for a 4-leg B&T (400 pounds of load, 100 pounds of lifting force).

Second, actual examples counter to your statement abound. High lift cranes employ one or more block and tackle arrangements, because they use a cable rated less than the crane's capacity would imply (because smaller diameter cable can turn a tighter radius). Rigging slings are assessed against a load by reducing each leg's strength based on angle of attack, then _summing_ the capacity of each leg (eg: https://www.stren-flex.com/load-calculator), such that the sling's capacity can easily exceed that of any single leg. Rope elevators, the ultimate human suspension system, use a minimum of 2 or 3 lift cables, depending on mechanism style, each of which is often run in multiple legs. The basis from which the elevator's working load limit is calculated is the _sum_ of these cable legs.

Were your principle enacted, elevators would not need to display a second, lower rating for single-item loads that might put more stress on some cables than a distributed load, because every cable would be rated for the entire load.

I assume you agree that each cable in a suspension bridge cannot support the entire bridge, and that Kinbaku has included suspending people of all weights since the late 1800's... traditionally with 6mm jute rope, used in many legs to multiple places on the subject.

Again, I'm happy to be proven wrong by a citation of an applicable standard that supports your claim.

As to side slipping, a cam device holds the rope it's on quite securely. In the absence of substantial side force or poor application, I don't see substantial concern there, certainly not in the conceptual post I made (and which I presume to be under discussion). It's definitely true that climbing ascenders typically have part of the housing covering the side and are superior in such a scenario.
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Re: CamJam XT tie-down

Post by Stretched out »


(It's worth noting that these don't even have the industry-standard rating of 5:1 for overhead loads not involving a person. Not really something I'd trust with my weight.)
Tie downs aren't generally rated at 5:1 as they aren't lifting equipment (Nor climbing or SB)
3:1 is common if there's actually a working load and breaking load marks. Or more often than not its just a working load that's stated. Or nothing at all.
There's a chart at the bottom of THIS PAGE that is useful reference
But "Force at Impact" is irrelevant to the point I think you were trying to make. Unless you posted the wrong link or you class 4ft as a wriggle.
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Re: CamJam XT tie-down

Post by Stretched out »

OrgasmAlley wrote: As to side slipping, a cam device holds the rope it's on quite securely. In the absence of substantial side force or poor application, I don't see substantial concern there, certainly not in the conceptual post I made (and which I presume to be under discussion). It's definitely true that climbing ascenders typically have part of the housing covering the side and are superior in such a scenario.
If the rope it pulled out to the side whilst tightening, it can grab half of a piece of paracord or a few strands of a twisted rope and feel like it's holding.

That's fine if your just pulling against it and unexpectedly get free early.
The potential for getting unexpectedly dropped was why I'd discounted them for suspension (not that I do anyway)
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Re: CamJam XT tie-down

Post by davisev5225 »

I've edited my reply a couple times because, after reading it, I realized I was talking out of my ass for a minute and going off on a tangent that didn't apply to the discussion at hand. If you happened to read this post immediately after I created it, my apologies.

Stretched out wrote:
davisev5225 wrote:Each component should individually rated for a minimum of 1900lbs capacity. These are not.
Theres a big discord between commercial working at height rules and sports/hobbies.

I guess you've not been sport climbing, as there's lots of climbing protection that is only rated to 2 or 3KN (449 to 674lb). By the above point, anything below 8.5KN needs to be recalled immediately. Or maybe people would be sensible and use them as part of a system.
I personally think sport climbers are insane for using such "low" ratings on their gear. I get that they want lightweight, but I'd rather have safety! :shock: Again, self-bondage is hardly "ideal" circumstances; it's best to render things as safe as you can possibly and reasonably make them. Spending a little more on better ropes, industrial hardware, etc. is a good idea. I keep 20+kN self-locking carabiners around for just that reason.
OrgasmAlley wrote:
davisev5225 wrote:Each component should individually rated for a minimum of 1900lbs capacity. These are not.
Can you provide any mechanical engineering standard or similar reference that ignores multiple legs in load calculations as you're proposing here? AMSE certainly doesn't. I am happy to proven wrong by a citation from any such body but I cannot imagine it.

First, clearly two identical ropes holding an evenly distributed load have twice the load rating of one of those ropes acting alone, in the same way two people can lift more than either can solo. Likewise, a block and tackle (the ultimate even distribution of load) is rated at rope strength * number of legs between block and tackle, and requires a free-end force of load / number of legs. Lifting a 400 pound load with a 4-leg B&T requires 100 pounds force and loads each strand to 100 pounds... not 400 pounds. Note that if we assume the vertical downward application of the lifting force, this also reduces the load at the lift point from 800 pounds for a simple rope and pulley (400 pounds of load, 400 pounds of lifting force) to 500 pounds for a 4-leg B&T (400 pounds of load, 100 pounds of lifting force).

Second, actual examples counter to your statement abound. High lift cranes employ one or more block and tackle arrangements, because they use a cable rated less than the crane's capacity would imply (because smaller diameter cable can turn a tighter radius). Rigging slings are assessed against a load by reducing each leg's strength based on angle of attack, then _summing_ the capacity of each leg (eg: https://www.stren-flex.com/load-calculator), such that the sling's capacity can easily exceed that of any single leg. Rope elevators, the ultimate human suspension system, use a minimum of 2 or 3 lift cables, depending on mechanism style, each of which is often run in multiple legs. The basis from which the elevator's working load limit is calculated is the _sum_ of these cable legs.

Were your principle enacted, elevators would not need to display a second, lower rating for single-item loads that might put more stress on some cables than a distributed load, because every cable would be rated for the entire load.

I assume you agree that each cable in a suspension bridge cannot support the entire bridge, and that Kinbaku has included suspending people of all weights since the late 1800's... traditionally with 6mm jute rope, used in many legs to multiple places on the subject.

Again, I'm happy to be proven wrong by a citation of an applicable standard that supports your claim.

As to side slipping, a cam device holds the rope it's on quite securely. In the absence of substantial side force or poor application, I don't see substantial concern there, certainly not in the conceptual post I made (and which I presume to be under discussion). It's definitely true that climbing ascenders typically have part of the housing covering the side and are superior in such a scenario.
These CamJam devices can't be used as a block or a tackle, since they lack the pulleys to function as such, so my point still stands. They are designed for a single line to enter and exit the device and act as a "brake" against the line slipping back through. There's no provision (without modifying the device and likely rendering it unsafe) for multiple points of attachment using the same line or a set of lines. There's just the carabiner head and the line "jam" mechanism.

If you're using a block and tackle, there's really nowhere to use these except maybe as a "one way" device for your output line to hold the load in position once you hoist it up. Even then, I'd be wary of trusting it with a human life.
Stretched out wrote:
davisev5225 wrote: (It's worth noting that these don't even have the industry-standard rating of 5:1 for overhead loads not involving a person. Not really something I'd trust with my weight.)
Tie downs aren't generally rated at 5:1 as they aren't lifting equipment (Nor climbing or SB)
3:1 is common if there's actually a working load and breaking load marks. Or more often than not its just a working load that's stated. Or nothing at all.
Correct, but I'm not talking about tie-downs. I was specifically warning against using these devices for suspension play. I have and do use them for non-critical anchors in my own play.
Stretched out wrote:
davisev5225 wrote:There's a chart at the bottom of THIS PAGE that is useful reference
But "Force at Impact" is irrelevant to the point I think you were trying to make. Unless you posted the wrong link or you class 4ft as a wriggle.
No, I don't expect someone is going to fall 4ft unless something has gone catastrophically wrong with their rigging. The point was to demonstrate that shock loads are higher than static loads, and that chart was one I had handy. There are other considerations, too, such as pendulum loads and tension from twisting (for which I was unable to find a simple reference).
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