How do you tote all your 'toys' with you in the tree?

[Treeman14]

Re: Sling / False Crotch nuance

Originally posted by Tree Machine
It's a sling if it has just the one caribiner in the end of it. It's a false crotch if you drop in another biner, gate opposed, or a locking biner.

Of course, none of us would EVER use the same piece of equipment for rigging and life support, RIGHT?

 

[Tim Gardner]

Re: Sling / False Crotch nuance

Originally posted by Tree Machine
It's a sling if it has just the one caribiner in the end of it. It's a false crotch if you drop in another biner, gate opposed, or a locking biner.

I tried enlarging the pic to see what it was but the image became to blurry.


I think Brett nailed it. I am sure it would have a block on the end or in a better location if it was being used for rigging.

 

[Kneejerk Bombas]

I just did a removal last week and found a throw bag and some throw line stuck up in it. Then I realized it was mine, from like ten years ago.

 

[Tree Machine]

Up in the top of that bur oak was left one of these pink slings I've been field-testing. I like em. Wish I hadn't forgotten that one. Here in the attached shot it's adjacent to a 7/16" tenex sling JPS suggested on to me. They're 32 and 36" resp.

I keep finding new ways to use them ----------------------------------------------------------------------
Originally posted by Tree Machine

It's a sling if it has just the one caribiner in the end of it. It's a false crotch if you drop in another biner, gate opposed, or a locking biner.

------------------------------------------------------------------------
I should also note that used as a sling, you would sling it in a choker configuration. As a FC you might want to use a 2,nd biner and in a basket configuration, like a friction saver.

You guys were right on ---no heavy rigging with these. Even though that pink flat sling is double thickness of regular 1" webbing, theoretically it should be twice the strength. Still, I don't lower stuff much bigger than me on a sling like this. For bigger lowers, I use load-rated lifting slings, or something I tied out of 2" wide webbing.

THEREFORE, because I never lower, or rig, a limb any bigger than me, never subject these pink slings to shock loads and I dutifully inspect my gear continuously (especially if I'm going to drop in a redirect), I use the gear as I deem necessary. Still, I will take these pink 32's to American Wire Rope and Sling, and have them tensile tested. I'm very curious how they will spec. out and I'll share the photos and the data after we do that.

 

[John Paul Sanborn]

That 7/16 tenex sling has a aound 1500# rating in a choker.

The rope has a 900# SWL.

Anyone remember the reduction for a stitched brummel? (through through burry)

 

[NickfromWI]

stitched brummell?

JPS- could you clarify what you mean by "stitched brummell?"

love
nick

 

[treeclimber165]

Re: stitched brummell?

Originally posted by NickfromWI
JPS- could you clarify what you mean by "stitched brummell?"

Lovey, look at this page. It's basic splicing instructions from New England ropes
http://www.neropes.com/splice/default.htm

A 'stitched Brummell' is a locking Brummell eye splice, stitched for extra security to keep it from coming loose when not loaded.

 

[NickfromWI]

stitched brummell

jps made it sound like it was a specific way to do a brummell splice. who knew that it could be so simple!

love
nick

 

[John Paul Sanborn]

Brummel vs locking brummel

Locking brummel passes through the working end then the working end is passed through the tail just formed. The nt eremainder of the tail is burried in the orking end of the rope.

In the brummel the tail is passed through, then cound down X picks of yarn, passed through again then burried. does not lock so it needs a lock stitch.

This is why I added "through through bury" at the end.

Thsis is the splice found on most Tenex slings. Even retail tress cords will have one locking brummel and one stitched brummel because matching the buries is such a PITA.

 

[treeclimber165]

I'm sorry, I was mistaken. I wasn't aware of two different types of Brummell splice. The 3/4" Tenex sling I bought from Sherrill had a LOCKING Brummell identical to the one shown on the website above. I've never seen this other Brummell splice you are describing, John.

 

[NickfromWI]

all this brummell talk

john, i got confused because there was mention of "stitched" brummell. it sounded new and exciting to me. and, while we're on the topic, wouldn't a tress cord be better with a locked brummell on each side? that's the way i make 'em!

love
nick

 

[Kneejerk Bombas]

The stiched brummell can be made about 15 seconds faster but is not as secure a splice as the locking brummell. It's about production, time is money.

Both locking brummell and stiched brummell should be stiched to keep the tail from worlking out, IMO.

I consider a stiched brummell, on a prussic loop to be a big liability, wait until one pulls apart.

 

[John Paul Sanborn]

Mike pointed the stitched brummels out to me at a WAA seminar. We took one over to Norm Hall and he showed us the stitch and explained why Stanley would be making them that way. If your making a few at a time, then 2 locking plices would be optimal, but if you are doing 60 you need some sort of efficiency.

Since the locked splice is not stitched, so it is moderatly faster on the first splice. with the second, you need to pass the first though an match the burries, which can add a lot of time if you don't get it just right.

Admitedly I was improvising saying stitched brummel since so many people are calling a locking brummel a brummel and I was not trying to confuse peopel between the two brummels wich I obviously did.

Back to the origional question Nick, what are the reduction factors in the two splices from the original cord tensil?? Since you are our Junior Splicemiester At Large.

 

[Tom Dunlap]

Rather than relying on a splicing student, ask the manufacturer or the teacher. Toss can be contacted here:
http://www.briontoss.com/wkstone-0....ntoss&Profile=message_board/showMessages.prof


Longstaff can be contacted too but I won't post his email in public. Drop me a note if you want it.

Tom

 

[NickfromWI]

JPS-
Good question. There are two ideas when it comes to the strength retention of the brummel. 1- It's all in the bury. 2- It's in the lock.
I stick with number 1. I had a piece of 5/8" Yalex tested by Yale Cordage in Maine. This stuff has a break strength of 16,380lbs. With a locked brummel on each side, the 10' eye-to-eye sling broke at about 15,500lbs. This is almost a 95% retention, but was not good enough to pass Yale's certification requirements. The reason I did not get 100%: Bury was too short. I knew (or thought) that in a locked brummel, the strength is that crossover. Therefore, I made the bury a bit shorter than recommended for what you call the "stitched brummel." When you do a lock, only some of the strands share the load, which lead to breakage. A longer tail allows ALL strands to share in the load and will eventually lead to a 100% efficiency.
I spoke with a Jamie, a splicer and sales guy at Yale, and he said this is the reason they do not recommend/require the locked brummel. With the stitched brummel, you can easily get that 100%, and like Mike Maas said...it's a tad faster.
However, I still prefer the locked. Here's my reason: When I make a 24" 3/8" eye to eye sling to use as a prussik, I know that i will NEVER subject that thing anywhere close to the 5,400lb breaking strength. Not even close. I feel more confident in the locked brummel at lower loads (like my 165lb self!). I always do stitch the bury, just to keep things neat. And even though on a 24" sling, I can't bury both tails as long as would be needed to retain 100%, I know the slings I use are extremely strong.
I think that's my bit on this. If you got more question, send 'em my way! Not too bad for a student, eh, Tom!?

love
nick

ps- Yalex is better than Tenex!!

http://www.yalecordage.com/html/industrial/single_braids.html
http://www.samsonrope.com/home/mi/12stranddetail2.cfm?ProdNum=172

 

[Tom Dunlap]

Nick,

I wrote a reply but the login guard ate it. I'll try to capture what I wrote before.

Not trying to be smarmy

An old skiing buddy who taught me rock and ice climbing was also a college art teacher. He had skills as well as an education background. larry told me that the most that a teacher could impart onto the students was 10% of the lecture topic. Without more study, it's not possible to learn anymore on the first go around, from the teacher. Now, if the student were to take that 10% and start to teach, the second generation student would only be able to abosrb 10% of 10% or .01% of what the original teacher/master knows.

You had the good fortune to learn from a true Master. You couldn't be better prepared to take on the job of splicing. Brion and Stanley are both very approachable and available. Not like many experts who don't associate with us Groundlings.

Thanks for sharing the details about the strenth loss of the splice. Good details.

Tom

 

[Stumper]

An interesting tidbit that is really neither here nor there. Wellington states that the ratings of their double braids are based on a properly made eye splice. Obviously a tested splice on their rope should always yeild at least 100% of rated strength. What that leaves you wondering is-- What is the actual strength of the unspliced rope? As I said it really isn't important but it does leave room to wonder how other manufacturerers rate their products. If the test standards are different then apple to apple comparisons are hard to make.

 

[Tom Dunlap]

Good point. This reinforces what I wrote in the "Measuring" thread. Unless we know how a test is made, we can't compare results.

Does W'ton eye splice the rope on both ends and anchor those eyes to the test machine?
Is the load applied to the rope at a steadily increasing rate? How many times have you pulled on a stuck throwbag and not had the line break. Then, give it a hard, quick tug and it breaks?

If you really want ot get confused, look at how many ways that rope stretch is measured. The Cordage Instiute doesn't have a standard way of measuring stretch. I spent time talking with Dick Hildebrand from Yale a couple of years ago about stretch. If a rope is loaded at a percentage of breaking strength then let slack for a while and then loaded at a higher percentage, the stretch will be measured differently than when the rope is brought up to breaking strength.

Like Shigo says, Define your terms!

Tom

 

[NickfromWI]

Reported Rope Strengths

Brion Toss told us that there are also examples of ropes breaking ABOVE their minimum breaking strength. This leads me to believe that just to be on the safe side, manufacturers underreport how strong their ropes are. If you do a slightly less than perfect splice, you still could get 100% of reported breaking strength. This is why I allow at least a 10:1 safety factor in all my climbing gear--and I usually go FAR above that. At 5000lbs break strength, a 200lb climber still has a 25:1 safety factor!!!Even when you account for everything, I should still feel confident in my ropes, knots, and splices.

love
nick

 

[Tom Dunlap]

good thoughts on safety factors, Nick.

On a doubled, 5k# rope, the climber would have a 50:1 safety factor. Pretty good margin! The tree is generally the weak point.

Tom