ART BlackBird for "MRT and SRT"

any reason you left Unicender off your list?
Meh....I didn't want to complicate my choices. LOL

Seriously, it's one that escaped my radar. If I don't decide on something mid line attachable, it'll be a ZZ. I need something for a 200' crane rope.

Using 2 climbers one day, I was setting slings while the other guy hung around the unions making cuts. On a tall cottonwood, my 150'er and OG ZZ almost fell short on a down slope. I had just over a foot on the ground. This ZZ lives on that rope. Was figuring if I got something mid line able, I could bounce back and forth between the 2 ropes when the ZZ wears out.

Not sure if I'd like the Uni for ball rides. YEARS back, I split tailed with a Blakes with binner, and terminated the other end with with a barrel knot to the bridge. I got the ZZ about 10yrs ago. I'm so used to it now, I'm not sure if I'd like anything else.

That was the only time I was a bit close to short on the descent. For the rest of that tree the OP cabled down to get me a bit lower on that hillside with 20' slings. I have time to decide ....

Also, I'm aware of the accessories available for the Uni to improve performance. Memory's a bit foggy on those. I think I'd like something GTG out of the box.
 
Meh....I didn't want to complicate my choices. LOL

Seriously, it's one that escaped my radar. If I don't decide on something mid line attachable, it'll be a ZZ. I need something for a 200' crane rope.

Using 2 climbers one day, I was setting slings while the other guy hung around the unions making cuts. On a tall cottonwood, my 150'er and OG ZZ almost fell short on a down slope. I had just over a foot on the ground. This ZZ lives on that rope. Was figuring if I got something mid line able, I could bounce back and forth between the 2 ropes when the ZZ wears out.

Not sure if I'd like the Uni for ball rides. YEARS back, I split tailed with a Blakes with binner, and terminated the other end with with a barrel knot to the bridge. I got the ZZ about 10yrs ago. I'm so used to it now, I'm not sure if I'd like anything else.

That was the only time I was a bit close to short on the descent. For the rest of that tree the OP cabled down to get me a bit lower on that hillside with 20' slings. I have time to decide ....

Also, I'm aware of the accessories available for the Uni to improve performance. Memory's a bit foggy on those. I think I'd like something GTG out of the box.

Forums in 2025 are all about the derail. I was just thinking about the uni for crane work, we do two climbers with crane assist a lot. I’m rarely on spar but it would be nice to have a device that is designed for srt based on the occasional need to choke off and rappel down without having to rack my brain on how to go about it on a hot day lol. Zz living on rope is my current go to. They say the uni is jerky, would love to hear if anyone uses it for this application.
 
I’m rarely on spar but it would be nice to have a device that is designed for srt based on the occasional need to choke off and rappel down without having to rack my brain on how to go about it on a hot day lol. Zz living on rope is my current go to. They say the uni is jerky, would love to hear if anyone uses it for this application
Reon Rounds uses the Uni in this method. Gets me thinking more......
Bringing this back to my thread from earlier. I will post it up no. I forget what I called the thread. It'll appearunder WHAT'S NEW

Sorry for the derail @moss now back to the BlackBird.
 
I have so many SRT devices and spend most of my time on spurs doing removals.... but I want this one too. Still, I'm going to exercise a bit of self control and at least give it a few months for others to use and report back.
 
The upper part does. I believe you could think of the lower bollards acting like the hitch below the RW
 
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So, if the upper parts work as a RopeWrench, in theory when the Blackbird engages on rope during ascending and then stopping, there should be some sit-back, like with the RW, right? This doesn't appear to be the case from what I can find and see in the videos.

As far as I know (correct me if I am wrong), there is no Multicender on the market yet that has zero sit-back in it the way a chest ascender like a Petzl Croll does.
 
So, if the upper parts work as a RopeWrench, in theory when the Blackbird engages on rope during ascending and then stopping, there should be some sit-back, like with the RW, right? This doesn't appear to be the case from what I can find and see in the videos.

As far as I know (correct me if I am wrong), there is no Multicender on the market yet that has zero sit-back in it the way a chest ascender like a Petzl Croll does.
That makes sense, Petzl Croll is designed for a specific purpose, going up and capturing progress. All it needs is a spring loaded cam. There’s a reason so many mechanical device designs are chasing the dragon, we’re asking a lot.

Hitch has more slop, guessing that the hitch “analog” in the Blackbird has much less than a hitch.
-AJ
 
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Technicallly, a toothed cam like the croll still has to rotate into place/lock to hold so there is sitback just very small. A RW/bird also rotates into accepting load and the lower pinch mechanism moves a bit too, again just small approximating "zero" compared to a hitch.

Moss, now I've got a reputation to uphold :)

I actually calculated RW sitback in RW design. HiPo :)
 
A neat combo tradeoff is RW sitback matching up wth the sitback required to set the hitch. You want the RW sitback smaller than the hitch sitback. "Upping" the RW with a rubber washer, spring, springy tether etc helps solve this issue. Compact low sitback hitches also help solve this issue.

Miss the days of manually setting the RW and the bruise on the top of your hand? : )
 
I just always think of sitback like a guitar string, where you can only approach your target from the one direction. With strings, that direction is moving up, tightening - if you tighten up too much then you have to go back down and approach it again on the way up. With ropes, that direction is down, descending, so with climbing and sitback, I always go just a little bit higher than I need to, then sit into the system, then lower just a bit into the best position. With this idea in mind, sitback doesn't bother me at all, generally
 

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