Rappin’ single can be tougher on ropes. Rappin’ double spreads load and abrasion onto two strands.
Advantages of using a block include (a) setting rope length for efficiency and (b) retaining a portion of the rope for contingencies (i.e. rescue).
In ACA courses we teach setting up blocks with (a) a figure eight on a bight and (b) a carabiner. Not sure why, but many of our students on this group seem to have latched on to that ‘biner block as their preferred option. If you encounter a situation where you feel the advantages of a block outweight the disadvantages, BUT you are concerned about that ‘biner getting stuck when you retrieve your ropes, use the figure eight block instead. It will pull just like an EDK.
NOTE: It is common practice to insert a ‘biner through the figure eight knot. This is done to make untying easier, not for additional security. If getting the ‘biner jammed is an over-riding concern, leave it off; the knot will still hold.
When tying ropes of different diameters together, some folks argue that it is best to run the thinner rope through the ring (knot on thicker rope side of ring), so when you retrieve your ropes you are pulling the heavy rope to retrieve the light one. Unfortunately, this practice dramatically increases the risks mentioned in the earlier thread. If you run the thicker rope through the ring (knot on thinner rope side of ring), you are, in essence, blocking the thicker rope with the knot.
Rich
Shane Burrows
>>A few months ago, I noticed that the screw link on the last rap in Mystery was very large. In fact, a small biner might pass through it and or at a minumum get stuck.
Dick Shear
I would like to add a word of caution on biner blocks. A few months ago, I noticed that the screw link on the last rap in Mystery was very large. In fact, a small biner might pass through it and or at a minumum get stuck. Just a heads up! Regards, Dick Shear
—– Original Message —– From: “rcwildone” rcwildone@yahoo.com> To: Sent: Monday, June 02, 2003 9:30 AM Subject: [from Canyons Group] Re: dual diameter rope rapel
> Rappin’ single can be tougher on ropes. Rappin’ double spreads load and > abrasion onto two strands.
Advantages of using a block include (a) setting rope length for efficiency and > (b) retaining a portion of the rope for contingencies (i.e. rescue).
In ACA courses we teach setting up blocks with (a) a figure eight on a bight > and (b) a carabiner. Not sure why, but many of our students on this group > seem to have latched on to that ‘biner block as their preferred option. If you > encounter a situation where you feel the advantages of a block outweight the > disadvantages, BUT you are concerned about that ‘biner getting stuck when > you retrieve your ropes, use the figure eight block instead. It will pull just like > an EDK.
NOTE: It is common practice to insert a ‘biner through the figure eight knot. > This is done to make untying easier, not for additional security. If getting the > ‘biner jammed is an over-riding concern, leave it off; the knot will still hold.
When tying ropes of different diameters together, some folks argue that it is > best to run the thinner rope through the ring (knot on thicker rope side of ring), > so when you retrieve your ropes you are pulling the heavy rope to retrieve the > light one. Unfortunately, this practice dramatically increases the risks > mentioned in the earlier thread. If you run the thicker rope through the ring > (knot on thinner rope side of ring), you are, in essence, blocking the thicker > rope with the knot.
Rich