Micro pulley

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Yes. The lower carabiner is attached to the blue and white rope which is the crossbridge on the saddle. The force applied to the lower opening of the pulley frame is downward and directly opposite the force applied to the upper opening in the frame of the pulley by the upper carabiner which is attached to the end of the rope going over the branch or through the friction saver, etcetera. Just doesn't look safe to me...
 
The biggest benefit I can see with that pulley, if it was fixed cheek, would be on the warp speed bridge of my glide so that I could use two biners when I climb on my vt.
 
And that is what I understand it was designed for: a roller attachment point for the bridge on a glide-style saddle.
 
If you look at the cheek plates they are clearly not designed to be loaded in the way they are in the picture. It may well be strong enough, it just was't meant to be loaded like that.
Pulley load ratings are when loaded directly from the sheave to the attachment point, unless indicated otherwise. Their load rating isn't for any "willy-nilly" direction you can think to load them.

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I guess they assume the angle indicated in the red, can be as wide as you want.
You can see the cheek plates spread apart as they near the sheave. If you laod it like this you'd want to be very careful about the carabiner selection. It will need to have a flat area so as not to tend to pull the cheek plates together.
 
Mike,
In the absence of a technical bulletin from CMI that describes the pictured use as a safe loading angle I'd agree with your assessment of the situation. I must be old school as I still hesitate to use aluminum products as my main means of support. Mainly use steel carabiners, though I do own a couple of nice aluminum ones.
 
Anytime more than one piece of rope is attached to a biner an HMS style biner should be used. A typical narrow top biner doesn't spread the load and shoves some of the gear over towards the gate. Not a safe climbing system.

My favorite cheap slack tender is a pincer dog leash snap. Take a look...
 
Tom Dunlap said:
Anytime more than one piece of rope is attached to a biner an HMS style biner should be used. A typical narrow top biner doesn't spread the load and shoves some of the gear over towards the gate. Not a safe climbing system.

My favorite cheap slack tender is a pincer dog leash snap. Take a look...

I'm in the market for a new rope and thought I'd pickup a micro pulley for slack tender. Maybe I'll leave out the pulley and just use a snap instead.

How effective is the use of a simple snap as a slack tender?
 
A snap that incorporates a swivel and has a large enough opening for the rope to pass through easily tends to do well.
 
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Dont mean to be thick about this but will it tend a blakes or other friction knot well also?
 
The micropulley I got (the red on petzl, I think) will not accept a single leash snap becauys it's too wide. I just use a biner or 2 dog snaps, it still advances the hitch, and can't be beat for coming back from a long limb walk. I'm of the same opinion as rahtree, I'm old-school but some of this equip is really indespensible, ridiculous not to make use of it.
 
gumneck said:
Dont mean to be thick about this but will it tend a blakes or other friction knot well also?
It will tend a blakes, but the blakes locks off so hard, it loses it's effectiveness, and almost takes two hands to pull the tail through.
But try it, and you'll get an idea of the advantages of being able to pull slack with one hand. Then you'll be asking yourself, "How can I make this thing advance easier?"
The answer of course is to change your blakes to a prussic of some kind. Once you do, you'll never look back.
The hard part is to just do it. You need some 5/16 or 3/8 cord (anything that breaks at more than 2500 pounds), a carabiner, and a dog snap or small pulley. Learn to tie barrel knots to attach the cord to the biner, and to tie a prussic hitch. Look at the picture above.
Good luck.
 
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