Alpine Butterfly let me down- Twice

[mudrat2]

Rather than the alpine butterfly knot mid-line, why not use a drop figure 8 knot?

 

[benjo75]

I have used that too. Not sure how it would untie on Tenex though.

 

[TheJollyLogger]

I have used that too. Not sure how it would untie on Tenex though.

Nothing untie on Tenex

 

[Bango Skank]

So how’d that bowline on a bight work out for you?

 

[preventec47]

I have used that too. Not sure how it would untie on Tenex though.

I should clarify that I opened my just received new rope this morning ( Tenex Tec) and I can see what everyone is talking about.
It obviously will NOT work, I made a big mistake, I am asking to return the new rope and exchange for Stable Braid 1/2 inch and pay
for extra costs incurred so my project is set back for a while. Meanwhile my 120 foot 5/8 nylon "practice" rope broke today at the
bowline knot up on the tree trunk when I really winched hard on the more power puller. The extra 300 feet of rope I am ordering
will be for my 2 or 3 to 1 mechanical advantage setup with my pulleys.. Thanks to the great input from Arbor Site members and
youtube videos I have seen two or three different prusik type mid line tie in techniques, a Figure 8 decender hardware option, and
several differnt knot alternatives including bowline on a bight, Artillery Loop, modified Prussic and something called the RosenCinch
knot that is very appealing and that supposedly will not jam with the creation of a mid line loop.

I also ordered today a 50 KN figure 8 descender and a 50KN steel carabiner today from Amazon.

I still need to figure out the exact specs of the prusik cords I would need for my new rope when I get it.

RosenRing cinch for 3 to 1 advantage


Prussik attaching to pull rope


Prussik attaching to pull rope at 7:20


Prussik details

 

[Bango Skank]

Hopefully they’ll work with you on the return.
If not, you can probably sell it here, but people would probably want lengths suitable for splicing slings.

Also you can make yourself some slings. This is the ideal rope to learn splicing on, it’s very easy to work with, and most errors can be undone. Don’t be intimidated, splicing this stuff is just following some pretty simple instructions. I used to feel intimidated by the idea of splicing something that would be critical to support a climber or hold a piece that would cause property damage or injury or death if it failed. Other rope construction is definitely trickier, but this stuff is simple and you don’t really need actual fids or specialty tools. Can use a wire coat hanger or piece of baling wire. A simple homemade fid my chopping a sharpie marker in half, or can taper the ends a little and tape them tightly if you’d be making an UltraSling.

It’s kinda fun and satisfying, especially when you see what the arborist supply shops charge for an UltraSling.

 

[TheJollyLogger]

I should clarify that I opened my just received new rope this morning ( Tenex Tec) and I can see what everyone is talking about.
It obviously will NOT work, I made a big mistake, I am asking to return the new rope and exchange for Stable Braid 1/2 inch and pay
for extra costs incurred so my project is set back for a while. Meanwhile my 120 foot 5/8 nylon "practice" rope broke today at the
bowline knot up on the tree trunk when I really winched hard on the more power puller. The extra 300 feet of rope I am ordering
will be for my 2 or 3 to 1 mechanical advantage setup with my pulleys.. Thanks to the great input from Arbor Site members and
youtube videos I have seen two or three different prusik type mid line tie in techniques, a Figure 8 decender hardware option, and
several differnt knot alternatives including bowline on a bight, Artillery Loop, modified Prussic and something called the RosenCinch
knot that is very appealing and that supposedly will not jam with the creation of a mid line loop.

I also ordered today a 50 KN figure 8 descender and a 50KN steel carabiner today from Amazon.

I still need to figure out the exact specs of the prusik cords I would need for my new rope when I get it.

RosenRing cinch for 3 to 1 advantage


Prussik attaching to pull rope


Prussik attaching to pull rope at 7:20


Prussik details

I want to acknowledge you, you just learned the most important lesson in this business... if it's not going to work, stop and reassess... you get plenty of times to get it right, and only one chance to get it wrong. I apologize if I seemed dismissive. It does get frustrating sometimes when homeowners ask for advice and then dismiss it or argue with it... speaking for most of the pros on here, we learned these lessons the hard way, and are just trying to help.

 

[Howard Justice]

The smaller rope with the sewn eyelets is commonly called a Prusik cord and are available premade in various lengths and diameters. I use 10mm diameter but am using a slightly thicker bull rope. You may need to go down to 8mm to get a good grip on 1/2" line, it depends some on how stiff the prusik cord and bull rope are, and how slick the covering is etc. My advice if you want to go that route is to get a 10mm and an 8mm diameter cord and do some on the ground testing first. Something around 30" to 36" should work to let you get enough wraps for a good grab.

There are several different ways to skin this cat. The Auto-block (French Prusik) shown in the video has a (undeserved IMHO) reputation for slipping easier than some other friction hitches but those making that claim tend to only use 4 wraps. 7 to 8 wraps creates a much stronger grip. I'd trust a 7 wrap auto-block over a std 3 or 4 wrap prusik. The Klemheist is another directional friction hitch that works well if enough wraps are used but for this one particular use I think the auto-block works great and it's pretty foolproof and quick to set up.

Agreed. 7-8 wraps. And you can make your own Prusik cord using double overhand knot at each end. There are others methods as well.

 

[pdqdl]

Well live and learn. I shopped all over for a week and found 300 ft Tenex Tec for $.72 a foot with free ship and looking at the strength and slightly lower elasticity than the other cheap ropes is why I picked it. There seems to be a big jump from dynamic stretchy ropes from about 1 dollar a foot to the static non stretchy ropes at $5 a foot and more. No in between that I could find. This is for a 15 or 20 tree project so I will attempt to baby the rope regarding abrasion and I will use large plastic ground spikes in the knots to hopefully prevent hard jamming in the mid line loops or any other knots.

Why don't you just abandon the difficult-to-tie knot that binds up and ruins your rope?

I have never understood the appeal of the alpine butterfly, except that it is equally strong when pulled in both directions. If you won't be pulling the same knot with equal force from either end of the rope, then don't use that knot! Bowline on a bight is equally strong in both directions, and it doesn't bind up irreversibly.

I have never found any documentation that suggests it is a good plan to stick stuff in the middle of a knot, except to facilitate taking the knot apart. When you stick a spike in the middle of your butterfly, you are sacrificing all the good things about that knot, and turning it into an unpredictable (therefore unsafe) knot to use.

The friction hitch is also a good plan.

And then there is this:

Another thing I’ll often do is a mid-line clove hitch and clip a steel carabiner in the loops. Clip your come along hook to the biner.

I don't consider a clove hitch to be a suitable knot for a carabiner. It can unroll from a slick round object. Use an anchor hitch or a double/triple fisherman's. If you are into knots, you will discover that the anchor hitch is just a clove hitch tied around a couple of wraps on the pole/ring/carabiner that you are using.
Bunt-line is a good option too, and also incorporates a clove hitch as part of it's structure.

 

[pdqdl]

This has been my go-to knot for the last 40 years. It's a bit sensitive to being dressed properly, but it holds great, and it won't bind up, even in Tenex.