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Tethered in Petersen's Bowhunting Equipment Issue

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But keep in mind, you never read of rescues stating "they were found at the bottom of the crag with a broken knot"
 
Bump for some pretty important information that may get overlooked...

Vtbow said:
The other thing to keep in mind is loads and safety factors. Everyone should read this if they are using amsteel of any sort for their bridge or and life support components: https://www.samsonrope.com/catalog/rope-users-manual

Just some quick calcs to throw out there for people to turnover:

MBS(minimum breaking strength) for Amsteel blue 1/4" is 7700lbs
Suggestd SF(Safety Factory *for life support(most fire and high angel rescue institutes*) 15

WLL(working load limit)= MBS / SF
=7700/15
=513lbs

So WLL for Amsteel Blue 1/4" for life support(according to manufacturer recommendations and usage specs) is 513lbs, and that is with a correct splice in each end in which the diameter of the eye of the splice never gets below 3x the diameter of the rope(so in in this case 3/4").

Hmm, my biners aren't 3/4"in diameter are yours? If my recollection is correct(It may not be, I dont have a source for this right now, but I'm sure I could find one) generally an average climbing rope(kermantle) with a bite running through a caribiner losers approximates 30% WLL at the bend...

General guidelines in a SINGLE KERMANTLE ROPE(amsteel is hollow core and will be MUCH MUCH REDUCED):
No Knot 100%
Figure 8 75-80%
Bowline 70-75%
Double Overhand Bend 65-70%
Ring Bend 60-70%
Clove Hitch 60-65%
Overhand 60-65%
Two Half Hitches (tested over 16mm diameter ring) 60-70%
Square Knot 43-70%

Again, AMSTEEL IS HOLLOW CORE. I believe samson states to consider knots in Amsteel decreasing MBS by 50%, but a lot of industry says, at least 30%... And I'm not even taking into consideration knot slippage...



Unfortunately that is kind of up to the manufacturer to determine. When a product is not specifically used for what it was designed for, there are no "best practices" that apply... Again, see the samson rope user manual link above.

**I URGE EVERYONE TO DO THEIR OWN RESEARCH AND NUMBERS ON THIS -- DONT TRUST ME, EDUCATE YOURSELF AND MAKE A CONSCIENTIOUS DECISION PLEASE **
Click to expand...
 
Vtbow said:
The other thing to keep in mind is loads and safety factors. Everyone should read this if they are using amsteel of any sort for their bridge or and life support components: https://www.samsonrope.com/catalog/rope-users-manual

Just some quick calcs to throw out there for people to turnover:

MBS(minimum breaking strength) for Amsteel blue 1/4" is 7700lbs
Suggestd SF(Safety Factory *for life support(most fire and high angel rescue institutes*) 15

WLL(working load limit)= MBS / SF
=7700/15
=513lbs

So WLL for Amsteel Blue 1/4" for life support(according to manufacturer recommendations and usage specs) is 513lbs, and that is with a correct splice in each end in which the diameter of the eye of the splice never gets below 3x the diameter of the rope(so in in this case 3/4").

Hmm, my biners aren't 3/4"in diameter are yours? If my recollection is correct(It may not be, I dont have a source for this right now, but I'm sure I could find one) generally an average climbing rope(kermantle) with a bite running through a caribiner losers approximates 30% WLL at the bend...

General guidelines in a SINGLE KERMANTLE ROPE(amsteel is hollow core and will be MUCH MUCH REDUCED):
No Knot 100%
Figure 8 75-80%
Bowline 70-75%
Double Overhand Bend 65-70%
Ring Bend 60-70%
Clove Hitch 60-65%
Overhand 60-65%
Two Half Hitches (tested over 16mm diameter ring) 60-70%
Square Knot 43-70%

Again, AMSTEEL IS HOLLOW CORE. I believe samson states to consider knots in Amsteel decreasing MBS by 50%, but a lot of industry says, at least 30%... And I'm not even taking into consideration knot slippage...



Unfortunately that is kind of up to the manufacturer to determine. When a product is not specifically used for what it was designed for, there are no "best practices" that apply... Again, see the samson rope user manual link above.

**I URGE EVERYONE TO DO THEIR OWN RESEARCH AND NUMBERS ON THIS -- DONT TRUST ME, EDUCATE YOURSELF AND MAKE A CONSCIENTIOUS DECISION PLEASE **
Click to expand...
I think the biggest concern with an amsteel bridge is at the bend. This looks like a pretty good bend and it didn’t break. https://saddlehunter.com/community/index.php?threads/amsteel-bridge-buries.8227/page-2
 
Amsteel is tough. We've got the reports to prove it. We have subjected our bridge to multiple shock loads at a TMA test lab that measured over 3000# force. And it didn't even phase it. That's multiple drops on the same bridge and carabiner. We've done our homework.

We did break a carabiner once though in back yard testing.

I'm going to be at a lab again this week playing around, and I will see if I can break a bridge using using carabiners as anchors.

My guess is it's gonna be a lot higher force than we need.,



Oh and btw, this month's Peterson's has an awesome saddle hunting article in it. Lots of familiar faces in there and of course a really cool cover.

a5277488091b6a8c2d521b83defda8c6.jpg


Sent from my SM-G955U using Tapatalk
 
fbwguy said:
The bottom line is safety is each person’s responsibility. Every ladder stand and climber manufactured today comes with a safety harness. I would estimate that 50% of those harnesses go unused. Your right someone will get hurt,people are stupid, that’s why McDonalds coffee has to be marked HOT. But this should not discourage Tethrd from moving forward and try to make saddles main stream. congratulations guys, you deserve the press
Click to expand...
I hate to say it but 50% is to low. I say 85%. Where I hunt, mostly ladder stands, I'm the only one who wears a harness. From what I've read it's not IF you are going to fall it's WHEN you're going to fall. I personally know 3 people who fell out of the stand. All hurt badly. One guy spent the night on the ground in 3 inches of snow. Out of work for 3 months. Always take your time and be safe. No shortcuts.
 
Bravo! As a former paratrooper, competitive speed climber using spikes, and professional arborist (retired), like many of the guys on this site I trusted my life to my gear. When I climb to band eagles in my state, I trust my life to my gear. When I climb to hunt deer in my Tethered saddle I trust my life to my gear. I Thank you, and my family thanks you. Keep up the good work.
 
Erniepower said:
Here you go



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Click to expand...
Cool! What diameter cylinder was used for the straight Amsteel break test? Did you repeat it with a diameter anchor at which the bend radius would be the same as an average biner? I.e. a steel biner or rapid link? Samson specifies bend radius' extremely specifically.

I understand the biners im using will fail first. Just curious!
 
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Kurt said:
Bravo! As a former paratrooper, competitive speed climber using spikes, and professional arborist (retired), like many of the guys on this site I trusted my life to my gear. When I climb to band eagles in my state, I trust my life to my gear. When I climb to hunt deer in my Tethered saddle I trust my life to my gear. I Thank you, and my family thanks you. Keep up the good work.
Click to expand...
There sure are some interesting people on this site. Sounds like you do some cool stuff.

Sent from my SM-G935V using Tapatalk
 
Vtbow said:
Cool! What diameter cylinder was used for the straight Amsteel break test? Did you repeat it with a diameter anchor at which the bend radius would be the same as an average biner? I.e. a steel biner or rapid link? Samson specifies bend radius' extremely specifically.

I understand the biners im using will fail first. Just curious!
Click to expand...
The Carabiners broke at less than 6,000. A full saddle setup broke at 9,000. The Amsteel broke at 11,000 pounds. Amsteel is the least worrisome part of the whole saddle.

Sent from my SM-G975U using Tapatalk
 
Erniepower said:
Amsteel is tough. We've got the reports to prove it. We have subjected our bridge to multiple shock loads at a TMA test lab that measured over 3000# force. And it didn't even phase it. That's multiple drops on the same bridge and carabiner. We've done our homework.

We did break a carabiner once though in back yard testing.

I'm going to be at a lab again this week playing around, and I will see if I can break a bridge using using carabiners as anchors.

My guess is it's gonna be a lot higher force than we need.,



Oh and btw, this month's Peterson's has an awesome saddle hunting article in it. Lots of familiar faces in there and of course a really cool cover.

a5277488091b6a8c2d521b83defda8c6.jpg


Sent from my SM-G955U using Tapatalk
Click to expand...
I was so pumped at work yesterday sorting magazines when I saw this on the cover can’t wait to pick one up to read it!
 
g2outdoors said:
The Carabiners broke at less than 6,000. A full saddle setup broke at 9,000. The Amsteel broke at 11,000 pounds. Amsteel is the least worrisome part of the whole saddle.

Sent from my SM-G975U using Tapatalk
Click to expand...
Understood. But curious what the Amsteel strength is in the actual application. Samson specifically states the strength is significantly decreased if a certain ratio of diameter to bend is not met. The anchor appears to have at least a 3" diameter to it. Again, not saying it isn't strong or strong enough, but i doubt it has that strength in the actual application. It's at least the same as the biners, I get that.
 
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