alternate brummel

attempting a tute here

Cool! I'll give it a try. Thanks.

Thanks Tami, I appreciate being encouraged to do these things.

Dave

That was pretty easy! MUCH easier than pulling line through itself .


Thanks Tami~!

I use a bastardized brummel (aka tuck splice?) where I just pull the line through itself twice then bury it. I don't use them for "structural" stuff though I have made 12 trap lines with them and they have never slipped at all... and those are conditions wherein they would slip. of course I am lazy though....

The idea of these splices is not to reduce the strength in the line by adding a knot. I reckon that one of these,mid way along a line, may weaken the line significantly.

Anyone got any authority on this?

Mike - has the punisher eaten a brummel vs. a simple tuck splice?

Sometimes one end is already fixed or simply too long... here is an alternative way to get the same Brummell
http://www.newenglandropes.com/SPL_12Strand_EyeSpliceBrummel.aspx

Cheers,

Klaus

I got NO Authority! but that is my understanding as well... HM line (dyneema, specta, vectran, etc) don't like knots and can reduce up to 70% of its breaking strength.

Oh yeah. Splices retain the most strength vs a knot. Bowlines cut themselves apart at about 60% of the ropes working load - sometimes less.

A brummel splice is our preferred 12-strand splice - however tapering the bury is critical to integrity of the splice. The line will typically break at the end point of the bury. If you think about it, the outer strands are taking the load, and the inner strands have less tension because of the transition. If you do not taper the bury, I've seen them fail at 50% of the working load because of the abrupt transition.

What is the difference between this brummel splice and a regular eye splice? Seems in both you pass each through the other and form an eye, then bury the tail? Are they the same just called different names?

No there is a difference... the regular eye splice the bitter end passes through the line a few times. The brummel is different... try Tami's example.. .it is much easier than the second link (its hard to pull the knots through the hole and then open them up again as in the second example) and will show the differece very well....

I think thats called a Single Braid Eye Splice Lock Stitch

A brummel actually forms a lock and regular eye splice usually weaves the tail back and forth through the same line. A regular eye splice can work itself loose if the line is repeatedly loaded and unloaded if it hasn't been whipped/lock stitched - which opens another can of worms...

Mike,

What I've been doing is a Brummel mid-line in my screacher and chute sheets and just luggage-tagging the made eyes through the tack grommets in lieu of adding shackles. I guess in this case you could say it's fabricating a Brummel with a super long tail and no bury.

I've had the chute up 20kt range, and the screacher in 15's and these splices haven't failed so far. And we're talking Fboat, not beachcat.

Maybe it's crazy, but it's working for me.

The fact that you are using a brummel is why it works.

I've been trying to do an eye splice like shown and having issues. When they say to "taper" the end, how the heck do you do that? Thats probably the biggest issue at the moment.
'
Thanks,

Clayton

Mike: I'm rolling with the brummel, but to be honest, I can't see a helluva lot of difference between it and a knot. Comments?

Clayton: See if this helps:
http://www.briontoss.com/education/BTR_book.pdf

At the end of these link is a good example (or 2) of how to taper that i recently found- http://www.precourt.ca/brummel_splice.pdf

here is another
http://www.samsonrope.com/site_files/12S_C1_EyeSpl.pdf

but is a regular easy buried splice weaker than a brummel? Or vice versa. I haven't ever had even a simple straight up (like on the samson page) eye splice come undone if the tail is long enough (which makes for a very long taper and smooth transition)

"A regular eye splice can work itself loose if the line is repeatedly loaded and unloaded if it hasn't been whipped/lock stitched - which opens another can of worms..."

I read that, but like I said... I have had 12 long tuck eye splices on trap lines for over 2 years and none of them have ever come loose. This would be the ideal situation for them to loosen. Oh, and none of them were lock stitched

YMMV

Mike, I was hoping for your rationale regarding any differential between a brummel-w/o-bury and a knot. Is there any? What I said, was:

"Mike: I'm rolling with the brummel, but to be honest, I can't see a helluva lot of difference between it and a knot. Comments?"

I'm thinking that w/o the bury, I might as well have just tied a knot in the line (which is how my covered (I think it's Staset) jibsheet is done, not by me) and since the line strength prolly exceeds the loading I'm ok. Or not. Which is why I ask.

?
urban dictionary - figured it out. your mileage may vary


Tami,
I think another way to look at it is if the loads are less than 50% of the line strength then barring other concerns (like the bulk of a knot) then there is no reason why you couldn't use a knot. With all the high tech lines, the chances of anyone exceeding the breaking strength is unlikely. It isn't "high tech" but the strength of 5/16 staset is 3500. I don't know exactly what the loads are on a jib on a F27, but doubt it exceeds 1000lbs. Even 7/64 amsteel has a 1200lb breaking strength. So outside of downhaul, stays then I think you are fine- even on a tri.

PTP, you have elaborated the reason why I'm using the "brummel solution" (sounds kewl, don't it.) to having shackles. I'm pretty sure the line's strength isn't being exceeded.

I'm just curious as to whether there is a difference in the 'brummel solution' as I've outlined it and actually tying a knot.

Hell, I'm still not absolutely clear as to exactly why tying a knot reduces line strength in and of itself, but I take the experts' words for it. I mean, I'm not arguing that, I'm trying to understand why it is. It seems to me that tying a knot is just another form of braiding, unless the knot itself slips. I'm not really doing a good job of conveying the concept I have in mind...

Tami, on the knot breaking the line thing, the reason I have been told (but not witnessed, yet) is that at some point, the line crosses over itself, forming what ever knot you have tied. When an extreme load is put on the line, the knot tightens to the point that the bent part, that crosses over, will cut into the line, and break it there, it adds a concentrated side load the line was not designed to handle, vs. a straight pull type load.

The advantages are clear...

you get to say "brummel solutiom" and "High Modulious Rope"... and sound cool like fonzie!

Ach, sooo...

Really, I swear, I didn't fail physics...

There are two problems with knots. The first is that as the knot tightens, it tends to cut itself in half. A bowline is a prime example - the small loop section of the knot slices through itself.

The other issue with knots is the loading of the braid. The outer part of the curve will take up most of the load, while the inner part of the radius will be "relaxed". This results in a greatly reduced breaking strength because you are really only using 1/2 the line to take up the load.

I really need to get a video camera, film it on the punisher, and place it on you-tube...

Get a high speed camera so we can see every 1000000th frame of it!... I bet lots of things would look cool exploding on it

I wonder if they'll let me borrow one of our 200 fps event triggered recording systems for that?

Bring it down. We'll fix a rummie and break some stuff.

May do that if only there were time for a side trip, I'm heading to Birmingham to visit a client and could have taken one to demo down there (and errrr....make a stop on the way back!).

Lets see how much force is needed to pull apart a 200 fps event triggered recording systems

nooooooooo....I don't sell enough of those for my commission to cover THAT.