3-strand Vrs.Dbl.Braid on GRCS

[frans]

The other day I was pulling a log over using my three strand 3/4" bull rope. I noticed it slipped on the drum even with three wraps, so I slapped on two more... worked just fine but I was running out of room on the drum. Later I switched to the Dbl. braid and it grabbed much better with fewer wraps.
Anyone have this experiance?
Frans

 

[Mark Chisholm]

I experienced that as well, Snarf. I believe that the 3-strand has less surface area since it is a twisted rope. And the dbl braid has a tendency to flatten a bit under load, causing more surface area to hit the drum. That's my thought anyway.

 

[Tony]

I have noticed rope slippage with the GRCS as well. It is important to remember that while the GRCS is a good tool the Harken Winch it uses is meant for the sail boat. Most boats that use a winch of this quality would in turn use double braid lines. Therefore, is is not unreasonable to assume that the designers at Harken had double braids in mind. As with all adopted, equipment it is important to note all limitations as well as advantages and adhere to them. Using adopted equipment as close as possiple to its original task, in my experience, will usuall assure smoother operation.

 

[TheTreeSpyder]

i believe there is less surface contact with 3-strands. i use it in tails, so that my weight's total is held tighter; digging deeper, by less surface area to share it over. i think that when the drum is turning and trys to exert force the opposite way, that same princi-pal works in the opposite way too.

 

[frans]

"Adapted Equipment"
Is any of our equipment not adapted?

Just to be clear: Greg rec. Dbl. braid to be used with the GRCS.

 

[Tony]

A great deal of our equipment is adopted. Some is not. For example, I cannot think of any other pursuit that uses a schwabisch prussik. My point was simply that to know the history of, and to apply it to, equipiment and techniques is a valuable asset. Just as when we prune a tree it is important to have a feel for its history (i.e. past failures, past prunning, drought stress etc).

 

[John_Paul_Sanborn]

Is the double braid a 3/4 rope? I've talked to Greg about thick ropes and he said it is designed more towards 1/2 inch rope. There's a story of him asking the lead engineer from Harkin about problems with fat ropes and he responded "Use smaller rope."

Greg recomends using five wraps before putting it over the thimble using the 9/16-5/8 stablebraid (never get a striaght answer on that stuff) If you have trouble getting that last one on you can crank it tight, let it dress up the through one more on. On real heavy stuff I've had the wraps pop as they slipped and thightend up more on the drum. No slipping in the jaws though.

 

[Mark Chisholm]

I understand the smaller dia. ropes to be rated for the self-tailer. I don't think that the larger dia. ropes are a problem for the drum, except that you are limited by the amount of space on the drum.

I also use two groundies (Tom talk) to winch a large section with a thicker rope. This way one man is always on the rope and he can also apply some tension while the winch is turning, thus adding the needed friction with fewer wraps.

 

[Riggs]

I used to use 1/2 dbl. to do some big time cranking , easy to put more wraps on so it won't slip (not the GRCS). Dbl. gets beat up pretty quick , I think . For half inch I use True Blue , that rope takes a good beating.

 

[Tony]

A thought occured to me today. My GRCS grips better in the rain. Theory: Increased surface tension between rope and drum. Seems to me that wetting the drum and rope may help with slipping problem. How much? Probably not enough, but the difference between grace and awkwardness is often measured in microns. I think I will wait for spring to test, however.

 

[Riggs]

In the early 90's , we made lowering devices out of boat winches , similar to GRCS . Unlike the GRCS , we put small drums to the lower left and right of the winch , instead of a self tail , you could come off the winch onto the spool below and with a 1/2 wrap never worry about slipping . A wet rope under tension is a mess . One winch we made had three speeds , the monster crank .

 

[John_Paul_Sanborn]

Joey Cornell was telling me somethinga bout a setup like that. 88:1 boat winch he rigged up with soemone out east.

 

[Riggs]

I think Joe knew the guys who rigged them up back east, but he wasn't one of them. Personally I think winching is the easy part , it's strapping them tight to the tree that can cause the most problems .