DDM
Addicted to ArboristSite
Anyone here have a mars bar? how well does it work?
Mars bar
- Thread starter DDM
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Stumper
One Man Band
They are a pretty good candy bar......Do you mean Marbars-The double ascenders with foot loop system?
pantheraba
ArboristSite Operative
I saw them for the first time at ITCC, same tree as TreeCo. They were very impressive, looked very easy to use.
Tree Machine
Addicted to ArboristSite
They're very, very easy to use. My wife has a version similar for her vertical caving rig.
The problem I see (for tree climbers) is that the ascent is such a small fraction of the time in the tree and if you use the MarBars, you either have to carry them around with you, hang them while you work or send them back down. Also the lower set of ascenders (feet) will pull the rope up, just because of the mild friction of the two ascenders and the clamping action of the cams. You either need to weight the rope beneath you, or have someone tension it for you. This isn't so bad on 11 mm rope, especially stiff, static kernmantle, but most arborists are on 13 mm soft hand and that just fits into the throat of these CMI ascenders.
A good footlock climber using dual ascenders will be on rope and half way up the tree before a MarBar guy is even rigged in and starting up. A single set of dual ascenders clips compactly on your saddle and is there whenever you need it. MarBars are two sets of dual ascenders, the cross bars and the slings that hook them together and you to it, plus the caribiners to make the connections.
MarBars, I think, would be indispensible for recreational climbing, say up monster tall trees beecause they're just so darn easy to master, even for a first-timer. Once you're up high enough the weight of the rope is greater than the friction and grab created by the lower set, and the need to tension the rope below you is no longer needed. They would be my first choice if going up giant redwoods, or for leading a first timer if our only goal was to get to the top.
Plus they're expensive, $350 in the Sherrill catalog.
I'm not here to dissuade anyone. They ARE as impressive as they look, but sometimes you need to look beyond the first impression, beyond just the ascent.
The problem I see (for tree climbers) is that the ascent is such a small fraction of the time in the tree and if you use the MarBars, you either have to carry them around with you, hang them while you work or send them back down. Also the lower set of ascenders (feet) will pull the rope up, just because of the mild friction of the two ascenders and the clamping action of the cams. You either need to weight the rope beneath you, or have someone tension it for you. This isn't so bad on 11 mm rope, especially stiff, static kernmantle, but most arborists are on 13 mm soft hand and that just fits into the throat of these CMI ascenders.
A good footlock climber using dual ascenders will be on rope and half way up the tree before a MarBar guy is even rigged in and starting up. A single set of dual ascenders clips compactly on your saddle and is there whenever you need it. MarBars are two sets of dual ascenders, the cross bars and the slings that hook them together and you to it, plus the caribiners to make the connections.
MarBars, I think, would be indispensible for recreational climbing, say up monster tall trees beecause they're just so darn easy to master, even for a first-timer. Once you're up high enough the weight of the rope is greater than the friction and grab created by the lower set, and the need to tension the rope below you is no longer needed. They would be my first choice if going up giant redwoods, or for leading a first timer if our only goal was to get to the top.
Plus they're expensive, $350 in the Sherrill catalog.
I'm not here to dissuade anyone. They ARE as impressive as they look, but sometimes you need to look beyond the first impression, beyond just the ascent.
DDM
Addicted to ArboristSite
I received a set with my latest ebay purchase. I wunder if it would be a problem using them on a single rope instead of double? Every picture ive seen there being used on a double.
Tree Machine
Addicted to ArboristSite
I would think you'd be OK, but don't know firsthand. I do use dual-ascenders on single rope all the time with no problems.
DDM
Addicted to ArboristSite
TreeCo said:
I agree,I'll use a Distel and micro pulley with it.
John Paul Sanborn
Above average climber
I use MarBars regularly for getting into tall trees. I mostly just use the upper and footlock vs using the lower. Only on 50+ foot pitches will I use the lower, due to lack of self tailing on the first few yards.
I started using Petzl singles, but was loading my shoulders poorly and found that the chin-up movement with the MarBar was much more comfortable.
Once I get up and retie, I speedline them down to a gorunder.
As for SRT, use the ascender and make a solid bar for them or contact Greg Liu on the BZZZ for the one he makes.
I started using Petzl singles, but was loading my shoulders poorly and found that the chin-up movement with the MarBar was much more comfortable.
Once I get up and retie, I speedline them down to a gorunder.
As for SRT, use the ascender and make a solid bar for them or contact Greg Liu on the BZZZ for the one he makes.
Buzzlightyear
ArboristSite Operative
Bugger i thought this thread was about chocolate lol
Tree Machine
Addicted to ArboristSite
If the ascender was rigged, very simply like either one of these shots, I don't know that a failure is possible. The rope CAN NOT escape the shell, period. Very little, then, can possibly go wrong, other than some freaky freak occurance.
Sorry, this is probably not the thread. The piece in the #2 pic will work on CMI doubled ascenders, as well as the Kongs.
Sorry, this is probably not the thread. The piece in the #2 pic will work on CMI doubled ascenders, as well as the Kongs.
Tree Machine
Addicted to ArboristSite
Here are the Kongs. I permanently affixed this simple device to the ascenders. I am never without it, and have no reason not to use it. Ever.
Stumper
One Man Band
Jim. I thought recommended practice was to have the security 'biner capture the rope as well as pass through the holes? The question of back up on double ascenders seems to involve one side slipping and -on doubled rope that means a fall unless something has been done to anchor the tails or close the system. Dan has worked out a knot to ride above the ascenders and provide back-up which is cool but I have to note that caving Expert Gary Storrick has some excellent arguments about why rope backups to mechanical systems are not worthwhile. To be fair though-the subject being discussedi this article is rappelling. When ascending some of the big neagtives wouldn't be a factor. http://storrick.cnchost.com/VerticalDevicesPage/Misc/RappelSafetyPost.html
Tree Machine
Addicted to ArboristSite
Roger that, Stumper. TreeCo, climber error. I feel an ascender could use a measure of protection over climber error, much like a safety belt offers protection against driver error. That's all. A simple and cheap measure of protection that wasn't there before.
We hashed this topic to death in this thread, http://www.arboristsite.com/showthread.php?t=17594&highlight=backing+dual+ascenders. We covered a number of different above ascender hitches and one of our members, Chucky, developed one hitch we believed had never been seen before. Nick from Wisconsin developed a new breed of tress cord that I doubt the world has seen and I bought 4 of them and have since used them exhaustively.
It was fully agreed on that the worst case scenario of an ascender failure was not the ascender failure itself, but for the rope to leave the ascender shell. Although not a 'true' backup, nor a guarantee that a cam won't fail, the capture pin does pretty much guarantee that the rope will not leave the shell. If permanently affixed to the ascender it assures a high level of compliance. The fact that it is cheap, and available at most any hardware or farm supply store also helps in the user adopting it.
I'm not claiming a perfect solution, but the fact remains that most ascender users use no backup whatsoever. The capture pin DOES offer an elevated level of protection above that.
We hashed this topic to death in this thread, http://www.arboristsite.com/showthread.php?t=17594&highlight=backing+dual+ascenders. We covered a number of different above ascender hitches and one of our members, Chucky, developed one hitch we believed had never been seen before. Nick from Wisconsin developed a new breed of tress cord that I doubt the world has seen and I bought 4 of them and have since used them exhaustively.
It was fully agreed on that the worst case scenario of an ascender failure was not the ascender failure itself, but for the rope to leave the ascender shell. Although not a 'true' backup, nor a guarantee that a cam won't fail, the capture pin does pretty much guarantee that the rope will not leave the shell. If permanently affixed to the ascender it assures a high level of compliance. The fact that it is cheap, and available at most any hardware or farm supply store also helps in the user adopting it.
I'm not claiming a perfect solution, but the fact remains that most ascender users use no backup whatsoever. The capture pin DOES offer an elevated level of protection above that.
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I love my Mar-Bars because they are the most versatile system I know of. You can ascend doubled or single rope using the same setup, and use just about any size climbing line you prefer. I like the bungee tether available from Buckingham over the fixed length tether that Sherrill sells with their systems. You can buy the bungee tether separately from http://www/buckinghammfg.com/ for about $20.
