Pull Test--Ice Tail Splice

[outofmytree]

Mallet, 1" carpentry chisel, electrical tape, and a big ol' chunk of wood. Press the chisel down hard and give it a good smack with the mallet. I get a nice clean cut everytime. Now when it comes to splicing.... I may have to make a trip to Ghillie cuz I am just not doing it right!

Moray, great posts! What hitch do you use when climbing?

Sweet. I am gonna do this tomorrow. Great tip.

 

[moray]

Mallet, 1" carpentry chisel, electrical tape, and a big ol' chunk of wood. Press the chisel down hard and give it a good smack with the mallet. I get a nice clean cut everytime...

Moray, great posts! What hitch do you use when climbing?

Great idea about the chisel--never thought of that. I like the Schwabisch, usually 3 over 2. I use a long tress cord, so the thick spliced parts of the Ice Tail don't contact the climbing line at all--it's all single-thickness.

 

[moray]

Pictures

Here are some pictures of my hydraulic testing rig. This first picture gives a view of the whole. The first and one of the toughest design problems is to come up with a very sturdy framework to withstand all the pulling forces. A multi-ton steel framework would be very nice, but money-wise way out of reach. Two big trees separated by about 20 feet would be fine, but I was afraid of damaging my live trees, and I didn't have a pair of dead ones that would work. So I chose a large butternut log with some big branch stubs still attached. The log is easily strong enough to withstand the forces, up to 10,000 lbs, and it is stiff enough that it stores very little energy that I need to absorb during recoil.

 

[moray]

The anchors are shown in these two photos. The slot at the lower anchor is somewhat rounded so that the chain can move in the slot. The chains are 20-foot lengths of G70 3/8-inch transport chain. Each one is always set up as a loop to minimize stress on the chain.

 

[moray]

The upper chain is connected to a very large shackle, which is connected to the load cell. The load cell is then connected directly to the closed end of the cylinder. This connection introduces an error of 2 lbs or so in the readings, so it would be preferable to have the load cell connect directly to the experimental rope. That is a very dangerous place to be, so to protect the load cell I always connect it as shown.

 

[moray]

The readout for the load cell is covered with a cardboard box with a porthole carved in the side. Thus shaded, it is very easy to read even in bright sunlight. All these pictures were taken while the test piece had 100 lbs. tension applied to it. A nice feature of the digital meter is that it stores and shows the highest reading it has received since the last reset. Thus after the rope breaks, the meter continues to show the force applied at the failure point.

 

[moray]

The cylinder is rated for 3000 psi and has a 24-inch reach. It is always used in retraction mode, so the right-hand port is covered with a couple of layers of cloth to keep out the dust but allow air to pass. At 3000 psi the cylinder would be pulling just over 10,000 lbs. The 5:1 tackle on the rug is used to pull the cylinder back out after a test. It is not strictly necessary but makes the job easy.

 

[moray]

The pump is well matched to the cylinder and is rated to produce 3000 psi. There is a way to change the mechanical advantage of the pump arm, but it is clunky and I have never tried to do it during a test. I will need to do it for anything above about 8,000 lbs. The pump is bolted to the wooden platform--without it it would fall on its nose. The hydraulic hose is 7 feet long and keeps me well away from the danger zone.

 

[moray]

The pump and cylinder are ready to stow. All this stuff is heavy and clunky, so I leave it outside under a tarp unless I plan to be gone for a long time.

 

[moray]

Knots being tested in a brand new piece of Bandit (Blaze). I think the big shackles have a WLL of 12 tons.

 

[stihlhere]

moray

After the gauge reached about 9800 lbs., the next pump stroke took the read-out out of limits, and the stroke after that broke the rope. .

moray FIRST thanks for the TIME AND PICKS.
NOW on to loadcell be very carefull taking your load cell out side of max range you will distort it and after that it's junk. And dont even wast your time having it rebuilt. I've changed out more of those than I care to mention even seen some visibaly bent. also NOT THAT YOU WOULD only apply load in intended direction.

thanks so much for the info as i have been wanting to go to a prusik cord have tested any beeline?

 

[outofmytree]

Hey mate.

As always, kudo's for the work. Rep coming your way as soon as I can.

Stihlhere if you search morays thread you will find much beeline work.

 

[stihlhere]

yea only had about 5 min yesterday check out thread and stopped when i got to the loadcell. I hate to make comments with out reading whole thread but had no time and wanted to throw that out about load cell. now on to search for bee line. thanks again a your efforts are very appreciated!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!:yourock: moray

 

[Adkpk]

I just started using Ice Tail e2e for my lanyard. It works much smother on the three strand than the Tenex.

Great thread moray!

 

[moray]

...NOW on to loadcell be very carefull taking your load cell out side of max range ...go to a prusik cord have tested any beeline?

Thanks for the warning. As it turns out, it is probably impossible for me to overload the load cell or the cylinder--both are rated to withstand 150% of their ratings. The most I have reached so far is 80%.

I haven't yet tested any Beeline, but I intend to one of these days. I know a lot of people use it. Ron reported some Beeline tests here:

 

[ray benson]

I see you are also knot testing. Has anyone tested a Bowline on a Bight, Figure 9 or Alpine Butterfly? I have used the Bowline on a Bight when putting a loop in the middle of a rope for tensioning a tree with a truck. Curious if the other 2 knots are stronger/better suited.

 

[pdqdl]

I read that report. Some of those numbers just don't make any sense. Especially the cover testing stronger than the core. Why not make it twice as strong by splicing with Class 1 (of course it is too tight a cover to make such a splice).

WHY, since the cover is "used" in the double overhand knot test, does the Beeline test at less than 1/2 of the rated strength?