Mechanical Advantage Definitions

Learning complex mechanical advantage systems starts with learning simple systems, and learning simple MA systems starts with learning a couple definitions. In this video, DMM Guru Taylor Hamel goes over the must-know terms involved in talking about mechanical advantage systems.

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hi I'm Nick Bonner for treesuff.com

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we're here with Keith Lesinski so first

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thing we're going to do is talk about

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hip thrusting yeah hip thrusting I mean

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that's been phased out for like a

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thousand years now right people still do

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it you'd be so you'd be surprised uh

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fair amount of people actually so I I

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think I remember how to do this let's

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see

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oh look at that we have the petzl l1d up

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at the top and you can see what it does

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is you can hear it kind of clicking so

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it spins really freely the one way but

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it gives me air is standing up right now

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look at this pretty much slack there is

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right this big slack and that's because

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the fall Factor right I fall and boom

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yeah

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okay so when I'm when you're up there

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hold up go up there again I know it's

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really tiring to hold yourself it isn't

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because of this pencil pulley I love it

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but right now your two hands are the

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only thing they're keeping you from

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going like four or five feet down fall

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onto the system I kind of assumed you

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would catch me so come on down oh got it

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this is the time where he tells me

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there's a pencil product that's gonna

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fix this oh am I right the one that's

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already on your harness wow so look at

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no look at the planning so right now

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you're on the short fixed length footage

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here but here you have the adjustable

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bridge that what you float your zigzag

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out at Arm's Reach so you can still hit

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for us but you can pull on the tail of

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the Rope below your zigzag instead of

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above the zigzag I think people

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misunderstand the use of an adjustable

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bridge I think a lot of people think

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that the purpose of the adjustable

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bridge on a harness is to adjust from

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like here to here to like somehow fine

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tune your reach that's not what it's for

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at all it's primarily for this technique

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exactly yeah all right so hit frosting

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and also for uh when walking it's

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awesome for or so I usually like to

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position it just Within Reach when my

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full body weight's on the system so I'd

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say push the zigzag up high and then

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hang on it

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PSA time

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a lot of people use cammed adjusters

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with like spikes on them for adjustable

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Bridges please don't do that get it get

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something like this or at the very least

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use a prosec don't use a camed adjuster

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bad

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don't do that

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okay so here we are we've adjusted this

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out let me get some weight in it you

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want to make sure you can still reach

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the zigzag so you don't strand yourself

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but now when you get both hands on the

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tail here

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zero Slack

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no sit back and that's also an

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efficiency thing right because like sure

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it's easy for me to hold but I don't

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have to take one hand off pull here I

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don't lose anything if I give any of it

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back what do I do if I mess up and I

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accidentally put this Out Of Reach oh so

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my Pro technique is with your left hand

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pinch the two halves of your bridge on

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the Carabiner there yeah

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um and then with your other hand you're

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gonna shift your right hip high and pull

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off with your right hand like that yep

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and every set do it again terrible so if

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you do find yourself with an adjustable

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bridge and you've set yourself too far

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out now you're able to reach much higher

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yeah and others benefited the adjustable

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bridge is if you pretend you're doing a

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little bit of a limb walk here oh right

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because you get out it when you're

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normal on a limb walk and you get out at

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that really far angle you still have to

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pull yourself back in hand over hand

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exactly so you're saying that

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if I'm all the way out like this yep

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fully set back to her harness

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then I'm able to walk myself back in

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maintain complete control and keep my

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weight in the Rope the whole time

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exactly no seesawing motion between

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weight on your hands versus weight on

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your harness and just sit back in the

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harness nice controlled limb walls

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it's pretty cool

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so that was a really good explanation of

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how slack can be introduced in the

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system and really what it comes down to

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is the impact on the climber if they

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slip with more slack there's more impact

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with less slack there's less impact

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thanks Keith