Beginners guide to rigging.......

[Paul Smith]

I was going to write similar Rupe. You put it a lot more eloquently than me though.

 

Do you just pretension the GRCS to take any excess stretch out or do you keep cranking as it goes over?

 

Pretension with the GRCS, unlock it and as it goes over pull the slack out and let it run.

[Adam Bourne]

but you dont count the leg you pull? surely that is your 1 and the others are the 2-1

 

Take SRT for example mate, that would be 1:1 then you would have a climbing system, then that would be a 2:1 adding 2 pulleys into a system makes 3 moving legs into the system creating the 3:1 hope this is more explanatory than it looks to me....

[Rich Rule]

Cheers Paul.

[Tony Croft aka hamadryad]

http://www.mcftoa.org/wp-content/uploads/2011/05/Rope_PP.ppt

 

 

I stand corrected, a lesson indeed!

[Adam Bourne]

http://www.mcftoa.org/wp-content/uploads/2011/05/Rope_PP.ppt

 

 

I stand corrected, a lesson indeed!

 

makes a change for me to be teaching you mate.....

 

your link does not work my end mate?

 

Edit: yes it does......

[Tony Croft aka hamadryad]

Rigging Techniques, Procedures, And Applications

[Rupe]

I was going to write similar Rupe. You put it a lot more eloquently than me though.

 

Do you just pretension the GRCS to take any excess stretch out or do you keep cranking as it goes over?

 

Kind of been answered already, but, you dont need to crank it at all, your not trying to lift or move anything against gravity.

 

Cranking can only be done when you have the full amount of wraps in place and then you wouldnt be able to lower it, so potentially dangerous when topping out, or negative blocking ("snatching", isnt really the correct term if using a decent bollard)

 

So, you just put on the number of wraps that you need for the piece being cut and pull tight (by hand) before the back cut goes in, the GRCS rotates as you pull tight so its very easy, then as the peice goes over you pull in any extra slack, and then release. Usually only ever amounts to a foot or so, or one pull in of your hands from full stretch to the body, if that makes sense.

[Peter]

Same procedure with a Hobbs, only with the Hobbs you are using a steel bollard rather than the winch drum. This is where I feel the Hobbs has the advantage over the grcs.

[Rupe]

How is that an advantage? I see them as both the same in that aspect.

[Peter]

I expect your winch drum is polished to a high sheen by now, but the ones I have used have been really rough textured and grabby, and make it hard to let the section run.

 

If you switch to the fixed bollard for smooth lowering then you lose the ratcheting action.