Rock Exotica Omni Block 1.1" Pulley for Use On A Harness Bridge - Is It Insufficient or Am I Just Trippin'?

Knotorious

That Guy With The Face
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I originally was looking for a swivel to attach to the bridge on my harness, but then I came across the Rock Exotica Omni Block. The particular one I was eyeballing on EBay (new) had a 1.1" diameter pulley sheave (which accommodates up to half inch lines) and rotating/locking/unlocking side plates which allow the user to insert the rope while the pulley is attached to carabiner, connected to the awesome swivel eye located at the top of the device. I figured to myself: this will allow me to have a swivel AND all the benefits of minial friction while positioning with my bridge AND this pulley is midline attachable, so I don't have to spend time disassembling any aspects of my harness in order to slide it onto my bridge and, if I want to take it off for whatever reason, it can be done quickly by simply opening the side plate and removing the device. Or if I want to switch to using it on my secondary, longer bridge, I can switch it over safely and easily at height.


I found a sweet deal on the 1.1" variant, the smallest Omni Block available, and I ordered it. It was a few days later when I re-realized that this pulley has an MBS of 23kN and a WLL of 5kN. I always am actively seeking out the strongest (within reason) hardware that I can find. All of my other pulleys have an MBS of 30kN. I'm beginning to feel like I made an impulsive decision and that I probably should have bought the 1.5" sized Omni Block, which has an MBS of 36kN and a WLL of 8kN. I really do not want to have to return the one that I got, purchase the bigger one, wait for it, etc....but I will if my concerns about the 1.1" pulley being a "weak link" in my climbing systems are validated on this forum.

What does everyone think? Am I overreacting and underestimating the strength and durability of the 1.1" Omni Block? Will I be safe using it as my primary attachment point on my bridge? One quick point to make is that, after attaching the pulley to one's harness, one can keep the side plate from being opened by driving the provided screw into a predrilled hole on the face of the pulley, so it is unlikely to ever come off my bridge once that has been done.

Or am I concerned for legitimate reasons. Perhaps those specifications are too close to the lower levels of what constitutes life support.

If anyone has any thoughts on this matter, your input would be greatly appreciated. I realize that generating 23kN would require a substantially energetic event, but I prefer to plan for the worst. Thanks for letting me ramble!
 
Welcome to The House! The pulley meets ansi requirements, so I'd call it good. I have my own problems with pulleys and swivels on a bridge, but that's my hangup. It's something a lot of people do, and if it was something I wanted to do, I wouldn't have an issue with that unit.
 
First, what is the rating of your saddle?
That should answer your concern.
Two, if you expect to suffer a 23kN load on your bridge, I don't think that the fact that the pulley holds or not matters much. In this story, the weak link is you. The max load you can physically handle is about 5 -6 kN. And definitively not in a work positionning saddle.
 
Your spine will be the weakest link. If you fall and generate that much force then I would have thought the pulley and bridge would be the least of your worries.

I will ask the question, why do you want a swivel on your bridge?

I used one about 15years ago to try and fix a problem of the lines twisting when climbing with a VT. All the swivel did was make the problem 10x worse.

I took it off after a week or two.
 
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Thanks everyone for helping to put this matter into a clearer perspective for me. I had somewhat of a feeling that this was the case, but now that I have confirmation on the matter, I'll put this new pulley to work with much greater confidence. Additionally, I rediscovered that the Petzl rappel rings (the type that can be opened via a gate and screw) are also rated for 23kN and I used those a few years ago to connect the leg loops, leg loop adjustments and my bridge neatly together on the harness I use. Therefore, I was able to establish that the sense of security I already had for some time regarding my harness could be reasonably applied to this new pulley.

Once again, thank you, everyone! Your input is greatly appreciated!
 
but with the rings you had 2, so almost double the strength :)

i shy away from „complicated“ systems and try to keep my system-chains as short as possible. swivels are inherently difficult/impossible to inspect and have failed in the past.

but to each its own.
 
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Oh, sorry,
Your spine will be the weakest link. If you clfall and generate that much force then I would have thought the pulley and bridge would be the least of your worries.

I will ask the question, why do you want a swivel on your bridge?

I used one about 15years ago to try and fix a problem of the lines twisting when climbing with a VT. All the swivel did was make the problem 10x worse.

I took it off after a week or two.

The reason why I want a swivel is because I generally prefer that my climbing systems be oriented as ergonomically as possible. Secondly, the last time I had a swivel on my harness, it helped me to position better overall and, although I encountered some undesired rotation when my feet were off the ground (or off a limb, etc), I found it relatively simple to inhibit such motion by using my lanyard. In particular, a longer than usual 15' lanyard. Thirdly, I feel like a swivel more or less inhibits me from putting any considerable twisting into my ropes because the swivel will begin turning after only minor amounts of resistance forms in a rope that is beginning to twist. I dislike how my ropes handle when they've been wound up.

If I'm being honest with myself, I think that - more than anything - I found and executed a good excuse for buying a pulley I had been eyeballing for awhile, one which will more than likely end up seeing more use as an MRS friction saving device or for light rigging. The reason I'm saying this is because a) I don't always like to use a swivel, which is why the midline attachable nature of this one is premier and b) the pulley only has one carabiner attachment point and I sometimes like to attach more than one thing to my bridge (in a fashion where they are all neatly lined up). So I'm thinking that I'll either buy a pulley with three attachment points and a swivel like the Rook (also from Rock Exotica), or maybe I'll install an new adjustable bridge (planned) and leave my existing bridge on (not planned) with a separate and different connection point type or, finally, scrap swivels altogether and put on a small four hole connection plate or go all the way back to basics with a large ring.
 
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but with the rings you had 2, so almost double the strength :)

i shy away from „complicated“ systems and try to keep my system-chains as short as possible. swivels are inherently difficult/impossible to inspect and have failed in the past.

but to each its own.

You have me suddenly aware that I can't honestly say that I know what to look for specifically. I would like to assume that any real damage would be pretty obvious because a part of the housing would be damaged or askew and/or it would fail to operate as intended on the ground or it would be inhibited by a part of itself, prevented from swiveling. But I'm not a swivel engineer, so I'm purely speculating.

I suppose it isn't any easier to inspect a triple action carabiner. The only real method (unless you know what the gate mechanics on the inside and have an x-ray machine) is presumably through basic observations for functionality and for damage, defects, etc. I would imagine that carabiners share this characteristic with swivels, along with any other 3-dimensioinal piece of equipment whose internal components cannot be completely viewed and repaired without inhibitory amounts of effort or expertise. Therefore, I'm not sure that a swivel is any more or any less risky to use. I reserve the right to be wrong, though. At any rate, thanks for your comment. You've given me something to investigate.

I hope that makes sense to other people. I'm also making the assumption that you probably aren't certain that they are any easier to inspect. The only reason I am doing this is because it just doesn't seem logical to me. That's all. But feel free to correct me and my potential presumptuousness.
 
The difference to me is a swivel can fail catastrophically. A gate failing on a biner is bad, but it's core function remains intact. There's a reasonable chance you'll see a broken gate before the rope falls out. You should always be giving the gear a quick look as you work, and keep your ears open. Fully functional biners have opened by grinding on trees/other ropes. Hasn't happened to me, but it's happened.
 
Ive beat on the 2.6 and 1.5 omni's and they've performed flawlessly. I wouldn't hesitate to trust my life to anything rock exotica makes.

I believe on the small one there's a way to put a set screw in to lock the release pin when you're using it for a bridge.

I think a little friction on the bridge is good but that's a whole 'nother topic.
You're cordage will be the weak point gear wise and as someone else mentioned you're body isn't going to withstand 20+ kn of force.
 
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The difference to me is a swivel can fail catastrophically. A gate failing on a biner is bad, but it's core function remains intact. There's a reasonable chance you'll see a broken gate before the rope falls out. You should always be giving the gear a quick look as you work, and keep your ears open. Fully functional biners have opened by grinding on trees/other ropes. Hasn't happened to me, but it's happened.

You're absolutely right about what you're saying here. I absolutely have more faith in a carabiner than a swivel.

Great insight. Thanks.
 
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