Knotting Sequence to Make a Releasable Weight

[JimK]

I worked out a tying sequence that allows a throw weight to release if the attachment ring is stuck or if the climber needs to manually slide the weight off.

I'm not sure if this serves a funcitonal need for the standard throw weight. I use the throw sock concept for tree entry and use the releasable system developed for that application.

If this makes a connection with you, then there's more detail posted on TCI's forum.

http://www.tci-forums.com/viewthread.php?tid=697

 

[Stumper]

Jim, Thanks for sharing. I'm not sure if I need that option but now It is in the mental bag of tricks.

 

[moss]

Will it work for these situations?

I've recently hung throwbags in what are probably typical scenarios:

1. In-tree throw. Bag goes over target branch then wraps throwline 4 times around second branch 3 ft. below first branch (didn't give it enough slack during thow). Friction on wraps is enough that there is no way to move the line by pulling. Solution: climb up and get it.

2. Ground throw to canopy. While working the bag into target crotch the throwline wedges into end of broken off stub. Bag won't drop, when I try and pulll it through it locks in the stub. Solution: climb up and get it.

For #2 I think your bag release set-up would have allowed me to drop the bag to the ground. For #1 not too sure.
-moss

 

[JimK]

Hi Moss,

As usual your assessments are on target. There's no direct way to remedy the line wrapping around the limb other than avoiding it. If the throw bag is stuck and the line is free, this will allow the weight to slide off when the climber pulls.

Regards,
JimK

Keep FIT - Fun in Trees

 

[NickfromWI]

Jim, that girth hitch with twist that you show has an official name. I'm sure this is the same knot you're using (hard to tell in the pic) http://www.arboristsite.com/showthread.php?t=19647&highlight=nice+knot

Good setup. I like it better than the leather you had before because any person could set this up. Some people (not me!) are intimidated by sewing.

love
nick

 

[JimK]

Nick,

Bummer it's not Nick's Ring Hitch. However, I'm very interested in trying Nick's Ring Hitch for this application. I see potential.

If you form a sloppy Girth Hitch and fail to dress it, then you'll have the set-up in the photo, which is how I came upon it.

Regards,
JimK

Keep FIT - Fun in Trees

 

[Sizzle-Chest]

I'm a little unclear. Do you need to pull extra hard to get the bag to release? How much force are we talking here? I wouldnt want that thing releasing on its own. But maybe i dont understand how it works

 

[JimK]

Sizzle,

The photo that I posted previously takes an enormous amount of pull to make it slip. If contact is direct to the ring, then the process of releasing begins rather easily. If contact agains the ring isn't sustained, then this configuration can be typically thrown and dragged through multiple crotches without a release.

I'd like to identify a configuration where ~60 lbs of force is required to slip the weight off. This is an estimate, but it takes about 10 lbs of force against the ring to start the release process. When a force directly presses against the ring, the mechanical advantage that holds the throw bag on line is lost.

When you make a weight releasable, you shift the risk from getting one stuck to having an unwanted release. There's numerous variables to dial this in. I plan to keep hammering at it until a simple, reliable configuration can be identified with a specific force.

This thing still needs a lot of experimentation. The concept of releasing a stuck weight makes sense to me. The key is minimize the unwanted release.

Regards,
JimK

Keep FIT - Fun in Trees

 

[Sizzle-Chest]

here's my method, i call it the Sizzler!

 

[moss]

here's my method, i call it the Sizzler!

Definitely effective in getting part of your throwline back

This reminds me of one of my beginning tree climbing attempts. After hanging all of my thowbags and one end of my climbing rope up in a red oak (for several days), I resorted to tying a clothesline to a large russet potato. This was inspired by someone on the TCI board (JimK ?) who had mentioned experimenting with potatoes as throwweights.

As I was throwing the potato my very amused neighbor asked what I was up to. Since it was close to St. Patty's day I claimed that I was hanging potatoes in the tree to celebrate the holiday.

So... I was able to climb on the other end of my rope and rescue the equipment after getting the potato over a branch. The main lesson of the day was don't try to pull a throwbag through a tight crotch. If I'd known JimK's bag release technique it might have been a different story.
-moss

 

[NickfromWI]

Jim- just to keep the record straight. What you called Nick's Ring Hitch is officially called the Bull hitch. (Much like the cow hitch, but a lot more stubborn!)

Jim, I've been following you on this one. I can't wait until you get it dialed for us!

love
nick

 

[JimK]

Nick,

The Bull Hitch (aka Nick's Ring Hitch) has strong merit for this application. It's the only way to make Slick Line work. Slick line is too springy to form a Girth Hitch with reliable tension. Also, it has a symmetry that's easier to thread than the twisted Girth Hitch. I thread the throwline between the two bridges.

Regards,
JimK

Keep FIT - Fun in Trees

 

[JimK]

Optimized Retro Fit

Nick,

Here's the best version so far. I still don't have my 60 lbs slip - yet.

Jim

 

[pantheraba]

No 2nd ring for releasable throw bag

A version of this thread is also running at TB...in case you don't go there, here is some of it...Jim K has a great idea. I tried Jim's way yesterday and it worked will. Dan Kraus wondered if it couldn't be done with a rubberband for friction and eliminate the extra ring. I tried the rubberband way today and it worked great for me. Here is a picture. Below is some of the discussion...

Quote from Dan K.:
I like that idea, what if you used one ring and ran the tail through a fat rubber band on the Throwball?

Dan, I tried the rubber band thing with only one ring...I keep the big long rubber bands that come on underwater disposable cameras so I used one.

I think you are onto something...worked very well for me. It was important to spread out the "legs" of the wraps of the rubber band to get enough friction to hold the tail of the throw line. At first, I had the bands all on top of each other but that didn't hold well enough. When I spread them out (as in picture) the friction was increased and it did fine. I made several 40-50 foot shots with my homemade hillbilly big shot and the bag stayed attached fine. When it did get stuck once, I pulled and pulled and it finally overcame the rubber band and munter hitch friction and let go...bag fell at my feet.

You can probably get too many wraps and get the friction too high...experiment and see. And I was able to use a fused end of the throw line with this setup.

Thanks to JimK for getting all this started.