Amsteel Daisy Chain

[Benny]

I've tried whoopie slings & while they work I'd prefer something quicker & easier like the Python Straps from Kammock.

Given that the Amsteel is so strong has anyone made an attempt at making a daisy chain suspension system with it?

I've done up a quick trial which hanging weighted out the back as we speak but I'm far from a splicing guru.

This is what I've done- fold length roughly in half & make a fixed loop. Rather than 2 splices & bury I done 4 splices.
- Leave approx 15" gap & do 4 splices. The 20" is the part that wraps around the tree. You can add tree protection under the line.
- Leave approx 3" gap & do 4 splices. The 3" gap is the hole you clip into.
- Reapeat for length of Amsteel.
- As I've only done a short trial length I didn't bother finishing neatly but I imagine it could be done by burying the short length then a tail splice on the long length.

If you can see this failing, better yet if you can think of a better way let me know.

The trial is currently in a vertical hang with 70kg weight. 3hrs in & looking good.

[Mouseskowitz]

I'm having a hard time picturing what you're talking about. Any chance of posting some pics?

[Benny]

Ha, I was confused just typing it & I've seen what I'm talking about. I'll try get some up this arvo.

I went out added my body weight to it a couple of times for 10secs & it didn't budge.

[fallkniven]

I use the same thing sort of for my Grand Trunk UL. I replaced the rope and S-hooks with 7/64 amsteel and whoopie hooks. Then I use a length of amsteel, fold it in half, and make a square knot all of the way down about every 6 inches. It does the same thing as a daisy chain. I just wrap around the tree and through the first loop, then hook the hammock on the appropriate knot. It's a real simple way rather than hours of splicing. Could take a picture tomorrow if wanted.

[Mouseskowitz]

I use the same thing sort of for my Grand Trunk UL. I replaced the rope and S-hooks with 7/64 amsteel and whoopie hooks. Then I use a length of amsteel, fold it in half, and make a square knot all of the way down about every 6 inches. It does the same thing as a daisy chain. I just wrap around the tree and through the first loop, then hook the hammock on the appropriate knot. It's a real simple way rather than hours of splicing. Could take a picture tomorrow if wanted.

The question I would have is strength of spicing vs knots. I'm not sure what type of splice Benny is using and its % strength. This issue with knots and amsteel is that you need a 8:1 bend radius to retain original strength and a square knot comes no where close to that.

Obviously knots don't degrade amsteel to the point of failure for our applications, at least I haven't run into any talk about it yet. But I'm just thinking the margin of safety isn't anything close to what most people would assume it is. I haven't been able to find any rigorous testing data on this subject as the groups that tend to testing (climbers and such) just say don't tie knots. So, all I have to go on is anecdotal accounts of logger and such tying knots and having failure as low as 30% of rated strength.

[pgibson]

Benny, I get exsactly what your talking about doing and believe that it might be a great idea. I would love to play with this some and see if I can splice up something that would work and still be strong and safe to use for a suspension.

Paul

[Benny]

Here are some pics

The test set up


The fixed loop


The hang loops. The carabiner is through the first & you can see the second separated.


As mentioned above each loop is spliced 4 times.

The hang test


There are 3 x 20kg & 1 x 10kg sandbags hanging from the trial. It's been there over 8hrs now & I've added my body weight a couple of time with no change.

It's far from a certified test but best I can put together.

[Aardvark]

"There are 3 x 20kg & 1 x 10kg sandbags hanging from the trial. It's been there over 8hrs now & I've added my body weight a couple of time with no change." Keep in mind your dealing with more than body weight, depending on hang angle, distance between trees, RL vs no RL, you could be looking at stress load much greater than body weight. Someone here did a post on force load, but my search-Fu is not so strong this morning. I am very interested in this thread though!

[Benny]

Yeah the I, Y, T anchor principles would apply to a degree but I have no idea of the details.

If the hang test goes all right I'll do up some real size daisy chains & set up the hammock & do the same.

Very keen to see if the splicing guru's out there have any input. One of those de-construction tests on youtube would be great.

[oldgringo]

Unless I'm missing something, those aren't splices, they're what appear to be Brummel locks. You're asking them to perform outside of their design envelope. Clearly, though, there is some strength there. <watching with interest>