Revo 3

Enough dropping weights, time to break it!

Actually I felt a bit sad, the Revo had taken all I could throw at it and responded better than I´d imagined, just breaking seemed cruel!
To test it I wrapped a thin Dyneema sling three times around the wheel and put it in my hydraulic pull tester, this is actually after the test which I stopped after the karabiner failed at 26.96kN and the sling also started to tear:-

The karabiner fixing-point ears showed no signs of anything happening:-



The centre axle had bent so the whole thing looked pretty sad, still wouldn´t have dropped you to your death though (unlike the rope, biner, harness and all the rest of the stuff)!



O.k, the poor thing was pretty f#cked by now so all that was left was torsionally testing the attatchment points, just for Joe! I´d borrowed a horribly expensive recording torque meter from the guys down the road (they maintain gas turbines), made a fixture to hold the Revo and measured what I could achieve with both hands-34.07Nm (25.13ft lbs). I´m 6ft tall, weigh over 200lbs and bend metal for a living, I´m not that strong but sure not weak either!
Then I broke the Revo clipped into a 12mm round-stock HMS karabiner held in a vice- 144.02Nm (106.22ft lbs). To put this in perspective for those who aren´t mechanics the lug nuts on my car wheels are tightened to 140Nm and with the Revo it´s like trying to do this with a 2 inch long spanner.



Conclusions;- It´s better than I expected, stronger than I expected, gives a softer catch than my GriGri and I´d lead rope solo on it. As a belay device it´s nothing.

Thanks for these 3 posts Jim!  I appreciate your efforts.  

Jim Titt wrote:As a belay device it´s nothing.

I’m confused by this wording. You like it as a belay device, or you don’t?

Have you read the first 2 parts???

Yeah, I read your whole post Jim. I was following your thoughts until you used the word “nothing” so I just thought I’d ask for clarification.

I’ve used a Revo for a couple lead belays in the gym and after playing with the locking mechanism when it pulls quickly without a hand on the brake I can understand how it could work well for lead solo. However, I didn’t like how little friction it applies when normally catching a fall, so I don’t have much interest in using one again.
Oh, and thanks for sharing your testing results!

Only after my last post did I go back to “latest posts in all forums” and see that you have 2 other related threads. Maybe they’re broken up because each focuses on a different aspect of the testing? Not sure, but I’ll go read those now.

Drew Nevius wrote: Only after my last post did I go back to “latest posts in all forums” and see that you have 2 other related threads. Maybe they’re broken up because each focuses on a different aspect of the testing? Not sure, but I’ll go read those now.

I knew there's a limit to how long a post can be and didn't know what pictures would do so split it all in 3 parts.

So the conclusion is that you're gonna have a really hard time getting it to fail or break while climbing? Sounds like it'll be great for lead solo and for guides to hand their clients to belay, but not so much for other things.

eli poss ·wrote,  13 mins ago
So the conclusion is that you're gonna have a really hard time getting it to fail or break while climbing? Sounds like it'll be great for lead solo and for guides to hand their clients to belay, but not so much for other things.

Eli, it is way more wall friendly, has fewer potential failure modes

& replaces this thing,


oops, thats the wrong picture, well you know what I mean....

Have fun in 'Lost Vegas' don't try to do anything I wouldn't try to do...

Wishing you safe sends & safer descents

Sub.`R`Side

Suburban Roadside wrote:
Eli, it is way more wall friendly, has fewer potential failure modes

& replaces this thing,

oops, thats the wrong picture, well you know what I mean....

Have fun in 'Lost Vegas' don't try to do anything I wouldn't try to do...

Wishing you safe sends & safer descents

Sub.`R`Side

Sure, but they're also like $500 so...

Anyways, I'm a ways away from lead soloing, sounds like a cluster and PITA to me at the moment so don't worry I won't be soloing on a revo. And yes, I will have lots of fun in vegas just as long as we can keep a 2 mile radius away from the strip. That place is a zoo and I want nothing to do with it. Have fun climbing east coast choss piles and writing incoherent posts on MP (although they've been getting a little bit more readable lately).

in terms of getting the revo attachment point to break-- seems like having the smallest possible "lever" would be useful-- eg attaching with an extremely small locking carabiner, or perhaps a maillon rapide? I still can't tell whether 144nM for breaking the attachment point is good enough or not... 

Awesome work Jim!

I’m glad to know my confidence in the device wasn’t misplaced.

I did just find an additional failure mode though. BLUF: do not rope solo wearing shorts with a draw string waistband.

Longer version: I was getting a few post-workout rope solo laps in on a wall I have access to and was “shorted” as I went to make a clip. I continued to try to feed rope for a few moments and began to pump out. I then down climbed a bit to try and figure things out. I tried to pull slack out with the thought of locking off if I needed to (I MMO the Revo to lock off) but couldn’t do this either. The device seemed totally jammed in place and I was on a slightly overhanging route and not feeling too happy. I finally noticed that the athletic shorts I was climbing in had a drawstring that had somehow come out of my shorts fit its way into one of the slots on the side of the Revo and got pulled around the wheel a few times and then jammed. For whatever reason the drawstring tips on the shorts were made from metal and the metal had become chewed up and jammed the wheel.  I ended up clipping my belay loop to one of the draws and it took me a few minutes to get all the metal bits and chewed up string out of the Revo. I eventually was able to take out the slack and tentatively lower. I cleaned and inspected the device and it seems fine other than some cosmetic scratches on the wheel. I’ve subsequently tested and climbed on it with no issues. It was a comically unlikely chain of events, but I figured I’d share it because weird stuff happens.

Based on Jim’s testing, it sounds like it would still have caught me if I had fallen, but I’d rather my rope and those metal bits didn’t interact. 

As has been pointed out the attatchment to you is actually a bit of webbing (your belay loop) and offers no resistance anyway, not quite the same as my vice bolted to the steel re-inforcement under my workbench. There is no realistic scenario climbing that will replicate the force I applied, it´s enough to shear a 1/2" bolt straight off.

Caveman Y wrote: Awesome work Jim!

I’m glad to know my confidence in the device wasn’t misplaced.

I did just find an additional failure mode though. BLUF: do not rope solo wearing shorts with a draw string waistband.

Longer version: I was getting a few post-workout rope solo laps in on a wall I have access to and was “shorted” as I went to make a clip. I continued to try to feed rope for a few moments and began to pump out. I then down climbed a bit to try and figure things out. I tried to pull slack out with the thought of locking off if I needed to (I MMO the Revo to lock off) but couldn’t do this either. The device seemed totally jammed in place and I was on a slightly overhanging route and not feeling too happy. I finally noticed that the athletic shorts I was climbing in had a drawstring that had somehow come out of my shorts fit its way into one of the slots on the side of the Revo and got pulled around the wheel a few times and then jammed. For whatever reason the drawstring tips on the shorts were made from metal and the metal had become chewed up and jammed the wheel.  I ended up clipping my belay loop to one of the draws and it took me a few minutes to get all the metal bits and chewed up string out of the Revo. I eventually was able to take out the slack and tentatively lower. I cleaned and inspected the device and it seems fine other than some cosmetic scratches on the wheel. I’ve subsequently tested and climbed on it with no issues. It was a comically unlikely chain of events, but I figured I’d share it because weird stuff happens.

Based on Jim’s testing, it sounds like it would still have caught me if I had fallen, but I’d rather my rope and those metal bits didn’t interact. 

Had you paid attention to the instruction leaflet you would have noted this danger is warned about  

Jim Titt wrote: As has been pointed out the attatchment to you is actually a bit of webbing (your belay loop) and offers no resistance anyway, not quite the same as my vice bolted to the steel re-inforcement under my workbench. There is no realistic scenario climbing that will replicate the force I applied, it´s enough to shear a 1/2" bolt straight off.

A quick course in free body diagrams would a) make this obvious and b) be less fun than snapping the thing with expensive testing equipment. 

Jim Titt wrote:

Had you paid attention to the instruction leaflet you would have noted this danger is warned about  

Wait, you read that thing?! 

Yeah, pretty silly on my part, wasn’t thinking about still being in my gym gear. 

Caveman Y wrote:

Wait, you read that thing?! 

Yeah, pretty silly on my part, wasn’t thinking about still being in my gym gear. 

Climbing in athletic shorts is worrying enough anyway, please consider there may be children or old ladies nearby.

Jim Titt wrote:

Climbing in athletic shorts is worrying enough anyway, please consider there may be children or old ladies nearby.

  

Thanks for doing all these tests. I had no doubts about it catching tower falls reliably, but those kinds of falls aren't my concern. And thanks for doing the breaking test even if it was the opposite of what I had in mind - looks like the attachment points will hold up well enough if on the belay loop. Overall, I still find its design problematic relative to the locking ears and the construction flimsy. And I still have points of reliability concern and don't find it has any advantages over the Eddy to warrant switching over to it. Wish it were so as I did have high hopes for it.

Thank you for all the work and the reporting. I bought the Revo mainly for lead soloing, and I appreciate the rigor you applied here.

The true test is still whether Healy can break it by hand, though. ;-)

Healyje wrote: Thanks for doing all these tests. I had no doubts about it catching tower falls reliably, but those kinds of falls aren't my concern.

I'd echo this. The concern for me with any device isn't performance in a tower fall situation, but rather all the wierd failure modes that can crop up in the real world.

For the Revo, my biggest concern is that force on the brake-side of the rope can disenage the locking mechanism. This is a good feature if it is used as a belay device (so you can unlock it and lower the climber), but could be a problem for rope soloing. How much force is needed to disengage the locking mechanism? Would rope weight from a long-ish cache loop be enough? Could this prevent the Revo from catching a rope-solo fall?