Help understanding advantage

I assumed smoother sheaves had to help.

BTW, I've heard people say always tie a line to my harness, never use a shackle. Any idea why? My hardware is meant to deal with a lot more weight than me.
 
They could be referencing the advice give to rock climbers that have a textile loop in front on their harnesses. Using a carabiner, more common than shackle use, has a possibility of rotating and becoming side loaded, not good. If you have a metal attachment point, they may not like the metal to metal contact.
 
Our bosun's chairs usually have nylon webbing loops, maybe with vinyl coverings and our halyards we use for raising our sails have SS shackles with positive locking pins rated for many thousands of pounds. Maybe they are mixing two sports?
 
JosefR said:
I'm a 52 year old sailor who needs to go 57' up a mast. I have rigged up some blocks and 240' line as in the 1st picture and attempted to hoist my 180#. Turns out, I can't lift #5 while I'm hanging from it, so I wound up pulling on #1. Problem was too much weight and line was slippery, even with leather palm gloves. Had it not been slippery, I probably could have done it, but it wouldn't have been easy. I think I have these numbered correctly, but if not, I think they are consistently wrong on both pictures. The fiddle block is ratcheting.
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So I am asking if I re-rig as in the following picture, will I have better advantage when pulling on #1? I can still let myself down by controlling #5. And I assume I'll need another 60' of line.

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In the drawings if the top is the anchor and you are the load. Pulling on rope #5 will give you only a 4:1 with ALOT of friction. Pulling the #5 rope downwards loads the cam kinda funky and makes a large amount of friction. If you were to pull upwards on 5 you have much less friction, but using a much weaker muscle group.
Pulling down on #4 gives you a 3:1 MA. Another thing to take into account is if the load is the input force you gain MA.

If you flip the system as in the second drawing you will get the fullest MA available from the system. However you are going to be pulling a shit ton of rope. I think a large part of your issue is also rope diameter. I personally avoid 7/16 and go with fatter ropes close to 1/2". I couldn't imagine hauling myself up with a 3/8.

I agree that a 3:1 should be more than enough. My wife and 9 year old son can haul themselves 50'+ with a 3:1. If you need a boost a simple prussic foot loop would be slow but very helpful. Just use a sit stand method.
 
You can only pull up on 5.
"Pulling on rope #5 will give you only a 4:1 with ALOT of friction. If you were to pull upwards on 5 you have much less friction, but using a much weaker muscle group." Which is it? A lot or less? And why isit not 5:1?

You can't pull down on #4.

I suppose if I hadn't started with the small double I show on top, I might have learned to go bigger earlier.
 
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Looking at your first diagram, pulling at spot 5, you are directly lifting a moving load from a moving platform (yourself). If you were standing at the top of the mast (fixed platform) and pulling up a 180 lb load, it would be much easier. By pulling at spot 1, you were pulling against a fixed pulley, which made it easier.

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JosefR said:
I assumed smoother sheaves had to help.

BTW, I've heard people say always tie a line to my harness, never use a shackle. Any idea why? My hardware is meant to deal with a lot more weight than me.
Click to expand...

Metal shackles can unscrew, if not of a locking construction. The singing tree quickie locks very well. Shackles are often made of steel, which can wear excessively on aluminum. Metal shackles are often made for other purposes, and thus sometimes have rough spots that can abraid textiles.
 
I used it last weekend, with leather palm gloves, to go up about 50 feet to re-run my identical 1/4" hoist pulley on the front of the mast from 3:1 to 5:1. So the line is still slippery and practically impossible to pull with one hand, it can be done, but is pointless as it is fatiguing to do so. But it does work if I reach up, grab the line, make a wrap on that hand, and pull with both hands. That gives me about 6 inches lift per pull. It is a full body workout because legs and torso are constantly working to stay centered on the mast. Descending was an issue in that I had to pull the loaded line out of the cam cleat and if I wasn't careful, the line would suck my hand into the cleat. The ratcheting pulley worked fine for slowing my descent, but I need to devise some sort of stainless steel hook, like below, to pull the line out of the cleat when it's time to descend. The 1/4" hoist pulley is giving me the same problem, chewing up knuckles on release...
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1/4" diameter rope and pulley? If so that is to small to be climbing with, and much harder to grip. Also leather gloves do not offer any extra gripping strength. In our industry leather gloves are typically used for lowering wood, where you actually want the rope to slip through your hand.

Do you have a link to the rope and pulleys that you have bought?
 
As Jehinten stated that type of glove from Metolius is good for lowering something. The gloves you have are for belaying a climber, not to climb up a rope. The Atlas type grippy gloves give substantial improvement to your gripping ability.
 
Rock/ mountain climbing is not the same as tree climbing. What is good for one doesn't always work in the other. If I got your gear correct this would be a safe and easy way for you to ascend.
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There are two options, short or long, blue or green.
Another thing to think about is using the mast to help get you to the top.
 
The gloves look good, definitely better than leather palms.

Either hitch is good, the Blake's has a single eye and doesn't clutter the shackle like the double eyes of the Prusik. They both grab when weighted,and are easy to slide up,and by pushing down on the top of either, you can descend.

The longer option allows you to mostly keep your hands below the hitch. You can only get an arm's length of slack if you should slip.
The shorter version's hitch is advanced by pulling up on the rope below the screw link. If you don't regularly tend the slack, a slip and fall could generate a lot of force with too much slack out.

A loop of rope inserted into a short piece of rubber hose can be girth hitched around the mast for a foot hold, to help climb or to rest.
 
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