I want to improve my climbing rig

[Carburetorless]

Carb,
Here is an atempt at drawing with words, niether are my strong suit.
If I wiegh 178lbs and am just hanging, motion less then I would load the point (where my rope tyes to my carabiner) with 178lbs, now if that 178lbs was not counter acted by a equal force I would not remain still, the 178lbs at anchor point has to be matched by an equall 178lbs at the friction hitch so the working end of the rope has to have a load of 178lbs and the standing end of the rope has to have 178lbs equals 356lbs at TIP, when I want to hoist my self up I have to put a down force of 178lbs or more due to friction on the captive end of the rope so that I can haul up the 178lbs that is still on the working end of the rope, DRT is a 1:1 Redirect (meaning I have to give 1 to get 1) set up, the only mechanical advantage is that the friction at the TIP allows delay in load, on a loss less pulley the load would be equal 1X climber pulling down one side of the branch,and 1x climber + friction pulling said climber up, so 2 x climber at TIP I am tecnologicaly retard to draw a picture on a computer, and have probably confused you with the way I talk in circles, but hope it makes sense,
Paul

If you connect both legs of your rope to your harness, then each leg will carry half your weight. 1/2 on the up side and 1/2 on the down side.

Think about it. Tying both ends of your rope to your harness doesn't increase gravities pull on you, you'll still weigh 178 lbs(not 356 lbs).

Think about it again, you're hanging from a rope, both ends are tied to you, you weigh 178 lbs, how much weight is on the TIP?

Think about it like this...

Like you said, in order for you to remain still or motionless there has to be an equal amount of force on the down side of your rope as there is on the up side of your rope....

Soooooooo, if you weigh 178 lbs, and both ends of the rope are tied to you it means that both ends are supporting your weight, which is 178 lbs, so the equation is YW/LR or Your Weight / Legs of Rope....

There are 2 legs of rope, so YourWeight / 2 or 178 lbs/2 = 89 lbs on each side of the rope.

You won't go from 178 lbs to 356 lbs by tying both ends of the rope to you; Now will you?

Think about it.

On the other hand, if you're climbing SRT it's different...

There are differences in the two systems, basically the difference is that one system is Dynamic(DdRT) while the other is Static(SRT).

Dynamic, it's a moving system, it's a big loop that gets smaller when ascend and it gets larger when you descend, it does part of the moving, so there's a trade off in the amount of effort it takes to climb the system.

Static, it doesn't move, it remains the same, so you do all the moving and all the work.

Now, since there's no trade off with the SRT system it's means that the 2 legs of the rope don't share the work load, and likewise they don't share your weight either....

As you probably know by now, it takes an equal amount of force on both sides of the rope to hold you in place, since you weigh 178 lbs, and the climbing system(SRT) isn't sharing the work load or your weight, then there has to be an equal amount of force on the anchored side of the rope to hold your weight, if you weight 178 lbs, then there's 178 lbs of force on the other side of the rope to hold you.

In either system there is the combined force of both sides of the rope on the TIP.

DdRT each side of the rope shares half your weight (89 lbs) combine those and you have 178 lbs on the TIP.

SRT each side of the rope has a force equal to your weight (178 lbs) combine those and you have 356 lbs on the TIP.

Get the picture?

 

[ROPECLIMBER]

Then phisics is wrong, a 2:1 system has mecanical anvantage and the haul line goes up 1/2 the speed and load as the pull line DRT is simply a 1:1 redirect, you have equal force and equal travel and travel speed on both ends of the rope, When you apply force to one side you are hauling the whole force up the other side,same as if the end of the rope was being pulled from the ground, look at it in motion,,
Take a flag pole for example same closed loop rope and a anchor point just no advansment capture but evry foot of rope you pull the flag goes up the same foot and you have the constant wieght of the flag on one side of the pulley and a cnstant force equaling the wieght of the flag on the other side, the flag doesent magicly share its wieght the rope carries the same tension (wieght of the flag) and the wieght with friction that it takes to counter that flags wieght, you have a gravity induced wieght on one side and a work induced wieght on the other side Ie flag x2 load on the minni pulley at the top of the pole, the only advantage is the redirect as you cant push rope, other than that it is a 1:1 redirect not a 2:1
I get your picture, but even though it makes sense I am still going to set up some tension scales and wieghts, because when pulling up say foot locking back up to redirect, all my wieght is on both sides of the rope gravity on one side and force equal to my standing wieght on the other side, putting a load of 2x me on tip, how can you wiegh more than you wiegh you dont you have to create the force (work) that countreracts the gravity.
Paul

 

[Customcuts]

 

[ddhlakebound]

Then phisics is wrong, a 2:1 system has mecanical anvantage and the haul line goes up 1/2 the speed and load as the pull line DRT is simply a 1:1 redirect, you have equal force and equal travel and travel speed on both ends of the rope, When you apply force to one side you are hauling the whole force up the other side,same as if the end of the rope was being pulled from the ground, look at it in motion,,
Take a flag pole for example same closed loop rope and a anchor point just no advansment capture but evry foot of rope you pull the flag goes up the same foot and you have the constant wieght of the flag on one side of the pulley and a cnstant force equaling the wieght of the flag on the other side, the flag doesent magicly share its wieght the rope carries the same tension (wieght of the flag) and the wieght with friction that it takes to counter that flags wieght, you have a gravity induced wieght on one side and a work induced wieght on the other side Ie flag x2 load on the minni pulley at the top of the pole, the only advantage is the redirect as you cant push rope, other than that it is a 1:1 redirect not a 2:1
I get your picture, but even though it makes sense I am still going to set up some tension scales and wieghts, because when pulling up say foot locking back up to redirect, all my wieght is on both sides of the rope gravity on one side and force equal to my standing wieght on the other side, putting a load of 2x me on tip, how can you wiegh more than you wiegh you dont you have to create the force (work) that countreracts the gravity.
Paul

Carbie has got this one right. A ddrt climbing system is close to a 2:1 system, and you do have to pull 2 feet of rope to advance 1 vertical foot. That's exactly why srt is preferred for long ascents, because you gain 1 foot for each foot of rope you pass, but lifting your whole mass with each "step".

Your flagpole example is flawed, because the running end is not attached to the load, so it really is just a re-direct.

 

[ROPECLIMBER]

Losing sleep over this, something deeper is truly wrong with me,
The flag is ancored to the working end of the loop the running end is pulling the equal wieght of the flag the wieght of the flag is still over there, and now the oppossing downward force it takes to move the flag including rope bend and pulley friction, is applied to the running end, only difference is there is no progress capture, (friction hitch) as long as you are hauling the flag, more than twice the natural grvitational pull of the flag is on the pulley and pully anchor point, once tied off then the two forces can equalize , but while hauling there is 2:1 load at top of pulley. I used that example because it is a closed loop like old school DRT.
In DRT the running end is only captured when stationary, when accending the running end is pulling the the same load that is still hanging on the other side of the pulley(branch), you pull 1 foot you go up 1 foot, to haul 1 lbs you have to pull 1 lbs plus friction 1:1, the advantage is the friction of the branch keeps the load off the friction knot, till it can be captured, it is still a 1:1 redirect just with a progress capture, I agree once you sit on both ends you have shared the load, but when you haul up at times you are pulling down the same wieght you are still holding or moving on the working end, IE 2x climber at TIP , set aside hip thrust, where I am reducing the load side, and taking advantage of the friction to hold it till I can capture it on the running end, but when I just haul up the running side I am loading the force of my wieght,one side of branch, plus the force it takes to haul my wieght including friction pulled down on the other side of the pulley (branch) the 2:1 is pointed at the TIP. For a mechanical 2:1 advantage the pulley would have to be moving with the load, then the rope would have to be pulled with the load (up) and the two atachhments would have to be on the tree, then you would have 1/2 the load, speed, and advancement. DRT has a fixed pulley (branch or friction saver) the video I posted earlier shows this simple as day,
the friction hitch is not sharing the load when advancing, the running end is bieng pulled through it, then when set the load will equalize, short of buying a 400lb can scale how can I show this.I cant heavier than my wieght but I apply my same or more wieght in force on the running end ocasionally when hauling back up short strecthes for a rederect or missed branch
etc, that is when I have the 2x at the TIP,

Rope and Pulley Systems-segment 1 - Pulley Basics & the Pulley Principle.pds.m2ts - YouTube
Rope and Pulley Systems: Segment 2 - The 1:1 Redirect and 2:1 Force Multiplication pds.m2ts - YouTube
Paul

 

[ddhlakebound]

Losing sleep over this, something deeper is truly wrong with me,
The flag is ancored to the working end of the loop the running end is pulling the equal wieght of the flag the wieght of the flag is still over there, and now the oppossing downward force it takes to move the flag including rope bend and pulley friction, is applied to the running end, only difference is there is no progress capture, (friction hitch) as long as you are hauling the flag, more than twice the natural grvitational pull of the flag is on the pulley and pully anchor point, once tied off then the two forces can equalize , but while hauling there is 2:1 load at top of pulley. I used that example because it is a closed loop like old school DRT.

No, it's not like ddrt, because the size of the loop never changes, and the load is hoisted, rather than the system being made smaller as the flag ascends.

In DRT the running end is only captured when stationary, when accending the running end is pulling the the same load that is still hanging on the other side of the pulley(branch), you pull 1 foot you go up 1 foot, to haul 1 lbs you have to pull 1 lbs plus friction 1:1, the advantage is the friction of the branch keeps the load off the friction knot, till it can be captured, it is still a 1:1 redirect just with a progress capture, I agree once you sit on both ends you have shared the load, but when you haul up at times you are pulling down the same wieght you are still holding or moving on the working end, IE 2x climber at TIP , set aside hip thrust, where I am reducing the load side, and taking advantage of the friction to hold it till I can capture it on the running end, but when I just haul up the running side I am loading the force of my wieght,one side of branch, plus the force it takes to haul my wieght including friction pulled down on the other side of the pulley (branch) the 2:1 is pointed at the TIP. For a mechanical 2:1 advantage the pulley would have to be moving with the load, then the rope would have to be pulled with the load (up) and the two atachhments would have to be on the tree, then you would have 1/2 the load, speed, and advancement. DRT has a fixed pulley (branch or friction saver) the video I posted earlier shows this simple as day,
the friction hitch is not sharing the load when advancing, the running end is bieng pulled through it, then when set the load will equalize, short of buying a 400lb can scale how can I show this.I cant heavier than my wieght but I apply my same or more wieght in force on the running end ocasionally when hauling back up short strecthes for a rederect or missed branch
etc, that is when I have the 2x at the TIP,

It's easy to check.....set your tip at a known height, and start with your working end clip or biner at a known height. Ascend to the tip, and measure how much rope you've pulled to ascend a known height. You'll find it's twice as much as the height you've ascended. 2:1

A ddrt climibing system is dynamic......the loop you're on gets shorter or longer as you climb or descend, but always both the working and running end are supporting the load, whether resting on the hitch, or moving upward through muscle power, or descending with friction.

 

[KenJax Tree]

Its like pulling a running bowline into a tree the more you pull the small the loop gets.

 

[ROPECLIMBER]

Size of loop has nothing to do with ratio, size of TIP would have more to do with it as the rope bend ratio would go up and down with size of TIP, the pulley (branch) stays the same size all the way up, The two ends of the rope stay basicly parrallel being pulled in the same down direction. If you hang a rope at standing level you can easily see the 1:1 the friction hitch is just a capture. pull one foot at the standing end and working end goes up 1 foot. Arborist climbing line is considered static line, it has very little stretch. the two ends could start at an infinite length and as long as they are basicly parrallel the 1:1 does not channge.
I give up on this topic.
My Girlfriend is in recovery from colon surgury in ICU (all went well no cancer)and I have not slept much,
will look at it again tonight. I will still choose my TIP as if 2x my wieght will be on it and more with friction, so I can live to prove my point.
Paul

 

[KenJax Tree]

Size of loop has nothing to do with ratio, size of TIP would have more to do with it as the rope bend ratio would go up and down with size of TIP, the pulley (branch) stays the same size all the way up, The two ends of the rope stay basicly parrallel being pulled in the same down direction. If you hang a rope at standing level you can easily see the 1:1 the friction hitch is just a capture. pull one foot at the standing end and working end goes up 1 foot. Arborist climbing line is considered static line, it has very little stretch. the two ends could start at an infinite length and as long as they are basicly parrallel the 1:1 does not channge.
I give up on this topic.
My Girlfriend is in recovery from colon surgury in ICU (all went well no cancer)and I have not slept much,
will look at it again tonight. I will still choose my TIP as if 2x my wieght will be on it and more with friction, so I can live to prove my point.
Paul

No cancer is always good hope shes doing well and recovers fast.

 

[ROPECLIMBER]

Thanks, Kenjax, her Dad is a colon cancer surviver, so they got it early, was the large type polip that turns cancerous and they sent it, and the section removed to biopsy but the surgeon said he thinks it was benine, and they got it out laproscopicly but still had to shorten large intestant so main risk now is bacteria infection. The doctor hasent seen her this morning so I am on call and nurse said she is doing good this morning they had said 3-5 days in hospital guess I will run by there before I head to jobsite, cant take flowers in the ICU so was hoping they had moved her, the rope discussion actually kept my mind off walking the floor, was up there from 11:30 am till 9 last night, Then could sleep till around 4:00 am or so,
Paul

 

[KenJax Tree]

Good to hear shes doing well

 

[Zale]

My eyes tend to glaze over when people start debating with each other DRT vs. SRT. If your TIP breaks it usually means you are too fat or too stupid for tying into a small limb.

 

[ddhlakebound]

Size of loop has nothing to do with ratio, size of TIP would have more to do with it as the rope bend ratio would go up and down with size of TIP, the pulley (branch) stays the same size all the way up, The two ends of the rope stay basicly parrallel being pulled in the same down direction. If you hang a rope at standing level you can easily see the 1:1 the friction hitch is just a capture. pull one foot at the standing end and working end goes up 1 foot. Arborist climbing line is considered static line, it has very little stretch. the two ends could start at an infinite length and as long as they are basicly parrallel the 1:1 does not channge.
I give up on this topic.
My Girlfriend is in recovery from colon surgury in ICU (all went well no cancer)and I have not slept much,
will look at it again tonight. I will still choose my TIP as if 2x my wieght will be on it and more with friction, so I can live to prove my point.
Paul

Best wishes for your GF, hope everything goes as well as possible.

Bend ratio only clouds this matter, and has nothing to do with the mechanical advantage or lack thereof in any given system. Bend ratio deals with the % of the rope diameter that is actually supporting a load. With a 3" dia. tip and half inch rope, the 6:1 bend radius does nothing to add to or take away from MA.

Let's try this another way........using a 120' rope.

Say you're at 60', cinched up tight to your tip, done with the climb and ready to rappel on your hitch (or descending device).

Cinched to your tip, you might have 2-3' of rope bearing load in your climbing system, and 117' of rope hanging below you. When your feet are about to reach the ground, you have 118' of rope bearing load, and 2' hanging below your hitch.

How many feet of rope have gone through the hitch or device for you to descend 60'?

 

[ROPECLIMBER]

Thanks DDH,
For the well wishes,
when you change the way you look at things the things you look at change, good perspective, that pulley video got me all bass ack wards,

When I am on the ground loading my TIP and run the rope both ways to check crotch friction, strength etc, working end goes up equal to running end coming down, this is why I called it 1:1, but I have known 2 times rope length for hieght of TIP since the first time I bumped my but! in '89. Why is this so hard to wrap my mush brain around,:bang:
Paul

 

[beastmaster]

Glad your Gals alright.
I read a big debate on another site that the RADs system of SRT is a 3 to 1 due to the way its set up? That really screws with my pea brain.
Correct me if I am wrong, but on SRT both sides of the rope carry your weight. That is if their both are straight up and down. If your tie in is at an angle the weight supported by it is lessened on that leg.
Again correct me if I am wrong, but on a single line the more points the rope touches, such as multiple branches, your weight will be distributed between them. right?
Those are things I believe to be true and take into account in my rigging, so I need to know if their correct. I often send my saw down and pull it back up again by hooking it in the middle of the rope with a biner. One end is tied off to me and the other is used to lower or pull, as the saw slides up or down, that way I am only lifting half the weight.
I do removals like that some times with one end tied off and the rope running through a pulley attached to a different tree or leader to the ground. Using a clevis I take piece between the tie in and the pulley. That way the weight is distributed between the two points. Right?
If this is a little off topic sorry. All this talk about ratios gets me excited and confused. I recently got me a set of double pulleys, now things get really confusing.

 

[Carburetorless]

When I am on the ground loading my TIP and run the rope both ways to check crotch friction, strength etc, working end goes up equal to running end coming down, this is why I called it 1:1
Paul

Yes it's true that the up rope goes up the same distance that the down rope goes down, it has to it's the same rope, it's just across a limb.

The climbing system though is 2:1, you only get half the return for your effort, because you're only moving up half the distance that your feet are moving down , because the down side of the rope is moving down half that distance while the up side is moving up half that distance. So you loose half of it when the down side moves down.

I'll try to explain it better.

When you climb SRT you get 100% return for effort, when you stand in your footloops you move up the same amount that you stand up, because the system is static the rope doesn't move down.

With DdRT you only get half return for that same amount of effort, because when you stand in your footloops the rope does move, because the system is dynamic the rope moves down half as much as you stand up.

 

[ddhlakebound]

I'll try to explain it better.

When you climb SRT you get 100% return for effort, when you stand in your footloops you move up the same amount that you stand up, because the system is static the rope doesn't move down.

With DdRT you only get half return for that same amount of effort, because when you stand in your footloops the rope does move, because the system is dynamic the rope moves down half as much as you stand up.

Uggggggg........

No, no, no, no, no. It's getting tiring correcting you. Please, follow these steps.

1. Close mouth/don't use keyboard.
2. Engage brain.
3. Learn a topic until you actually understand it.
4. Commence public discussion of topic.

You always go straight to 4.

anyway.....

With ddrt you get half the return FOR HALF THE EFFORT (plus friction). Not half the return for the same effort. Or have you already forgotten your 178 pound post from yesterday?

Or do you think there is a difference in the work performed in pulling 2 feet of rope with a 100 pound load, or pulling a 200 pound load 1 foot up a rope?

 

[ddhlakebound]

Correct me if I am wrong, but on SRT both sides of the rope carry your weight. That is if their both are straight up and down. If your tie in is at an angle the weight supported by it is lessened on that leg.

I think this is incorrect. You can never get below 100% of load with a redirect. I believe the load on the angled anchor leg would be increased as the angle increases, up to 90 degrees, then falls back toward 100% as you get closer to 180 degrees. Not 100% sure, and have not found a reference yet.

Again correct me if I am wrong, but on a single line the more points the rope touches, such as multiple branches, your weight will be distributed between them. right?

"Touches" is a bit unclear, but generally yes, the more points a line runs over, the greater the weight distribution between them.

Those are things I believe to be true and take into account in my rigging, so I need to know if their correct. I often send my saw down and pull it back up again by hooking it in the middle of the rope with a biner. One end is tied off to me and the other is used to lower or pull, as the saw slides up or down, that way I am only lifting half the weight.

I do that sometimes too.

I do removals like that some times with one end tied off and the rope running through a pulley attached to a different tree or leader to the ground. Using a clevis I take piece between the tie in and the pulley. That way the weight is distributed between the two points. Right?

Yes, but at 120 degrees of angle between the two anchor points, each leg is supporting 100% of load. @90 degrees each leg supports 70% of load, over 120 degrees the load of each leg increases over 1x loading, up to 1150% on each leg at 170 degrees. According to "On Rope" anyway.....

 

[Carburetorless]

I think this is incorrect. You can never get below 100% of load with a redirect. I believe the load on the angled anchor leg would be increased as the angle increases, up to 90 degrees, then falls back toward 100% as you get closer to 180 degrees. Not 100% sure, and have not found a reference yet.

Actually the way the load is distributed on the TIP changes, it goes from all the load being applied downward to part of the load being applied sideways in the direction of the angle.

An easy way to think about is that a rope pulls along it's length, if the rope is pointing west and has an angle to the east that turns and points down, then the rope is pulling the TIP to the west and down.

The load is applied downward, and to one side to a greater or lesser degree depending on the angle that it crosses the TIP.

 

[Carburetorless]

Uggggggg........

No, no, no, no, no. It's getting tiring correcting you. Please, follow these steps.

1. Close mouth/don't use keyboard.
2. Engage brain.
3. Learn a topic until you actually understand it.
4. Commence public discussion of topic.

You always go straight to 4.

anyway.....

With ddrt you get half the return FOR HALF THE EFFORT (plus friction). Not half the return for the same effort. Or have you already forgotten your 178 pound post from yesterday?

Or do you think there is a difference in the work performed in pulling 2 feet of rope with a 100 pound load, or pulling a 200 pound load 1 foot up a rope?

Again you're misinterpreting what I said.

In DdRT you get half the return for the leg motion imparted on the rope. If your stroke is 2' then you only get 1' of upward movement, because half of that 2' is dispersed downward, while the other half is dispersed upward.

If you were to film yourself climbing DdRT and SRT, then play it back in slow motion, you'd see that your legs move the same amount in each, but that the movement is dispersed in two different directions in DdRT.