Backups in SRT

Jimmy wrote a good description of the 'red zone' for ascender use...any time the rope isn't weighted and vertical/parallel to the handle/spine of the ascender.

Years ago I learned about this 'red zone' and take special precautions when I go there. If I do, I make sure that my lower/chest ascender is working perfectly and is in the best position. Then I have many ways to advance my upper ascender into the 'red zone'. My attention is focused on my upper but I monitor my lower.

Getting arbos to clip the upper hole is likely to almost eliminate the ascenders popping off the rope.
 
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Jimmy wrote a good description of the 'red zone' for ascender use

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Damn I thought I was the one that wrote about keeping it parallel.
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Years ago I learned about this 'red zone' and take special precautions when I go there. If I do, I make sure that my lower/chest ascender is working perfectly and is in the best position.

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Just made a comment regarding this on Steve's site. This does tie in well with the OPs original question. If the middle ascender in a 3 ascender set up is as secure and functions as reliably as our attachment in doubled rope technique, there would be no need to back up the upper ascender. It would be operating only as a handle grab to advance your position.

The Croll is smooth in operation but really does not address the safety level required. The Unicender does work in the center position and, though its camming lock method is very rope friendly compared to a toothed ascender, it is more complex and bulky than is required for this function.

So in my opinion we have a need for someone to develop a proper central attachment point that will handle SRT for the tree industry.

Dave
 
Holly...yes...you made the point too...here's a hug for not acknowledging you too!

Dave,

'Steve's site'??? What am I missing?

What safety level does a chest ascender not provide for us? Would you elaborate?

I wonder if something 'like' the Petzl ASAP would be an answer? The ASAP needs to be on a tether though.
 
"Steve's site" Mr. Bulman and friends across the pond.


Because the Croll functions on the same principles as your typical hand ascender, it is subject to all of the failure modes that we are concerned about: twigs and debris defeating the safety latch, bark being jammed into the cam preventing the teeth from grabbing and such.

If we are to rely on something in this position, these need to be addressed. You need to have absolute confidence that it will function appropriately, always. I have not found a hitch that meets this requirement that is still fluid on the rope for SRT. I really like the camming action on the Uni and I think this is where this design needs to be headed. But something designed specifically FOR this position for SRT.

Dave
 
"So in my opinion we have a need for someone to develop a proper central attachment point that will handle SRT for the tree industry."

Petzl already makes it. It is called a Microcender. It is inexpensive, light, compact, cannot "pop" off the rope, moves smoothly up the line, and doesn't have teeth to damage the rope. I have been using this as my second ascender for four years now with no problems.

If you are really safety conscious it is also very easy to use a handled ascender for your top ascender, a Croll for the chest ascender, and a Microcender underneath the Croll as a second backup. I have done this when taking beginners up 300' old growth trees just to put my mind at ease. Having the third ascender only adds about 30 seconds to setup and removal of the system. Even production tree work can handle 30 seconds of lost time.
 
Dave,
Regarding, "...a proper central attachment point that will handle SRT for the tree industry..".

I was just thinking, I believe we've about come to the conclusion that one problem, the ascender coming off the rope, is due to the safety being inadvertently disengaged, allowing the cam to fully open. Perhaps the simple solution to this is not the biner through the top holes, but a safety design where the biner prevents the safety from fully opening, kinda like the Pantin. Hmmmm, a Pantin just might be the solution to that center attachment.

Of course the Pantin is susceptible to debris just as any other ascender is, but to me that's a matter of climbing discipline and practice to regularly inspect gear, esp. at 'sensitive' times or manuevers.
 
Boy, Ryan, I couldn't agree more! I use Microcenders a lot, and now prefer the PMI Grab as shown below in a RADS setup I came up with a while back. You're exactly right - it will not come off rope. We still need to be diligent with regards to debris.

4092742132_7c659c41a1.jpg
 
With the thought that the mayjor problem seems to be object making there way between the rope and the cam, it comes to my attention that a deflector at the top of the ascender would be the answer. Something that could be one of two ways. The first being a removable snap on piece and the second would be something that would be a permanant piece. I think I like the second more, also it is more geared for tree people. I had in mind a plastic domed shape cover that would stop almost everything from entering the area inside. The ascender coming off the rope is a technique issue so we all know to fix that would be practice. I should patent something like that.
 
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Petzl already makes it. It is called a Microcender.

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I see this as an option, not the final solution. It still uses a single cam which are vulnerable to debris. Plus it lacks an attachment point for an upper harness/shoulder straps that facilitates upright positioning.

Dave
 
I'm not so sure Fairfield, I think keeping gear clean and in good operating order is the responsibility of the user even, well better, especially while in the tree.

The thought of making a car that will prevent accidents comes to mind.

I guess it comes down to if a climber is so busy and moving so fast that he can't check his gear appropriately, is that really the fault of the gear, the climber, the profession?
 
Fairfield your line of thinking is kinda the direction ascenders should go.That is ascenders designed specifically for tree care that address the techniques and obstacles faced in tree care.Also it we be a good idea if they meet the minimum strength requirements for the industry.
 
Ron, my thinking is to not give the climber the idea they do not need to keep there gear clean or in wrking order, or not watch as they climb. My thought is that no matter how much you try as a climber you cant have your eye on all your gear at all times. I like to think of this idea as Im trying to make the tire have more traction on a wet road but not change the shape of it. If that makes any sense?
 
Fairfield,
I know, I guess I'm just a bit pessimistic about this.

I've watched the same approach in the firearms industry - everything in the world proposed to make the gun responsible instead of the individual.

I understand a climber, especially a production climber, can't watch his gear every second, but if we add something that gives him yet another excuse not to watch his gear are we not now making him even less safe? A false sense of security of sorts?
 
Ron, there will always be that chance with the furthering of saftey that you will make the user less mindfull do to false sense of security. I agree with what you are saying but if we can stop something from happening that is happening to mindful climbers, I think it would be my responsablity as a climber to do so. P.S I am a fellow NRA member I see what you are saying.
 
A cuff or gaiter around the ascender could be a patch.

I can visualize one now. The cuff part that is at the top would use stretch Cordura since it is very abrasion resistant. Add in a bit of elastic to keep it snug on the rope. The closure would have a bit of overlap with Velcro closure to make it easy to install/remove.

http://www.altrec.com/images/shop/detail/swatches/OR0/1.49393_e.jpg

The catch with adding more layers of 'safety' is that the system becomes more complex leading right back to where we are now...tree climbing is one of the more complex rope access disciplines. The other trap is that layers of safety can create a mental invincibility feeling.
 
Fairfield,
I think we've always been on the same thought train; it's just that I've seen too many times where we relieve people of certain responsibilities and things get worse.

I'm not saying that's what would happen in this case, but it could. And, yet I see what you're saying too, a example might be a cam with a secure lock is better than a cam with no lock.
 
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The catch with adding more layers of 'safety' is that the system becomes more complex leading right back to where we are now...tree climbing is one of the more complex rope access disciplines. The other trap is that layers of safety can create a mental invincibility feeling.

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That's what I'm concerned about too. Part might just be me, I firmly believe safety is my responsibility rather than a piece of gear, etc. Yet it is undeniable that we do need gear as forgiving as it can be and yet still be practical.

My riding lawn mower has numerous safety switches on it. One is a seat switch - if you attempt to get off the mower to do something the seat switch cuts the engine off. That was the first thing I disabled. The idea is to improve safety through gear so people, well I guess you see where that's going, but the inconvenience to me, simply made me defeat it.
 
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The catch with adding more layers of 'safety' is that the system becomes more complex leading right back to where we are now...

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Exactly. A thoughtful redesign/new design would be far better.

As long as things are being changed, if the lower attachment point of this new tool was attached to both the bridge and shoulder harness points that were attached to other areas of the saddle in a life supporting manner, it would address the redundancy on the bridge that Blinky brought up earlier.

Dave
 
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