What are benefits of bowline on a bight?

Bowline based knots are very similar to Figure Eight based knots as far as Knot Efficiency (Strength rating). but are easier to untie (after Heavy loading, Hard falls, and long term loading) I use the bowline on a bight when setting up rappels of double bolt anchors as its much easier to adjust the individual loops to clip offset bolts and faster to tie than the two loop figure eight. I have no issues untying rappels that have been set up and had tons of rappels all day long.

Bowline based knots allows me to utilize as many loops as I want to make.

Bowline= 1 loop

Bowline on a bight= 2 loops

Triple Bowline= 3 loops, also endline improvised harness as it gives a waist loop and 2 leg loops for improvised rescue.

Bowline on a Coil= X number of loops, This was a traditional tie in / waist belt before harnesses or even swiss seats, Most did 4-5 wraps around waist and tied off

Figure Eight Based Knots are easier to inspect from a distance, compared to Bowline based Knots.

I use a bowline on a bight for:

1. Tie in on sport. Easy to untie. If you fail to complete the knot you will know as the tail will be at your knees 

2. Building belay rigs for banshee belays. It is strong yet can be untied at the end of the day. So the sling is worn in different parts each day 

3. As a master point on a 2 bolt belay rather than an ovethand when using a thin sling. Easy to untie each pitch

4 to look good. It is a knot of much beauty 

I don't use it to form two independent ears to clip to stuff. I always clip both ears to the same things. 

David Coley wrote:

As a master point on a 2 bolt belay rather than an ovethand when using a thin sling. Easy to untie each pitch

Ingenious!

David Coley wrote:

I use a bowline on a bight for:

1. Tie in on sport. Easy to untie. If you fail to complete the knot you will know as the tail will be at your knees 

2. Building belay rigs for banshee belays. It is strong yet can be untied at the end of the day. So the sling is worn in different parts each day 

3. As a master point on a 2 bolt belay rather than an ovethand when using a thin sling. Easy to untie each pitch

4 to look good. It is a knot of much beauty 

I don't use it to form two independent ears to clip to stuff. I always clip both ears to the same things. 

A little help please on the master point.  How does #3 work?  I cannot visualize it. 

David Coley wrote:

I use a bowline on a bight for:

1. Tie in on sport. Easy to untie. If you fail to complete the knot you will know as the tail will be at your knees 

2. Building belay rigs for banshee belays. It is strong yet can be untied at the end of the day. So the sling is worn in different parts each day 

3. As a master point on a 2 bolt belay rather than an ovethand when using a thin sling. Easy to untie each pitch

4 to look good. It is a knot of much beauty 

I don't use it to form two independent ears to clip to stuff. I always clip both ears to the same things. 

this would give you 4 loops. Perhaps useful as independent clip in spots for leader and follower?

Live Perched wrote:

A little help please on the master point.  How does #3 work?  I cannot visualize it. 

Edit to add: this is what I pictured when reading about #3.   I am not qualified to judge the strength of this configuration, and it is entirely possible that I misinterpreted the description.

Edited again to add:  https://www.mountainproject.com/forum/topic/108283153/bowline-for-master-point-knot

mbk wrote:

Excellent! Takes advantage of every element of the looped sling and bowline and eliminate the weakness of the bowline, the carabiner prevents untying.  Elegant.  Thank you. 

How to tie a bowline on the bight masterpoint is shown halfway down this page:

https://people.bath.ac.uk/dac33/high/6TheBelay.htm#belaysthatlargelydontusetherope

David Coley wrote:

How to tie a bowline on the bight masterpoint is shown halfway down this page:

https://people.bath.ac.uk/dac33/high/6TheBelay.htm#belaysthatlargelydontusetherope

oh, I thought you were suggesting a new way!  (#3 vs #2)

Should I remove the photo above?

David Coley wrote:

How to tie a bowline on the bight masterpoint is shown halfway down this page:

https://people.bath.ac.uk/dac33/high/6TheBelay.htm#belaysthatlargelydontusetherope

David, I read through that section but I'm not seeing the bowline on the bight masterpoint until the section on Banshee belays. Is that what you meant?

Search the page for

With 2 bolt belays you might find using an alpine butterfly easier to untie than an overhand.

Andrew Climbs wrote:

I LOVE the bowline on a bight for this purpose but also have concerns about slippage in the event of a cut loop. I've used it regardless when appropriate, but I'm now wondering if there is actually a way to prevent the possibility of slippage all together?

ABOK 1075 ("bowline-on-a-bight and bowline")

Doubling the bowline allows you to tie the rope to a tree at the middle of the rope. This provides two secure lines coming from one tree. This allows you to use a single long static rope in two separate top rope setups. Alternatively, you could use one side to build your anchor, and leave the other side neatly coiled at the top of the cliff so that it will be available later if you need to rescue a climber. I have used the second line to secure myself while I am building an anchor with the first line. Although it isn't needed, clipping the bight to another part of the rope can provide an additional backup to prevent the bowline from becoming untied.