EDK rappells

[egaibrev]

Can the EDK be used to join two ropes of different diameters for a rappell? How different can the diameters be?

 

I've heard conflicting things.

 

Discuss.

[tomtom]

What knot are you calling the EDK?

[Ireneo_Funes]

paging CBS...

[selkirk]

the EDK is an overhand knot with long tails.

[catbirdseat]

paging CBS...

I don't know the answer. Intuitively, it would seem there would be a limit on dissimilar sizes, but don't know what that would be. I probably wouldn't use it to join 6 mm cord to 10 mm rope, for example. I know for a fact that the double fisherman works no matter what the size differential.

[Ireneo_Funes]

I've used it to join a 10.5 and something a little smaller than a 10, and that worked fine. Not really interested in finding out what the limits are through personal experience.

[Gary_Yngve]

http://www.xmission.com/~tmoyer/testing/EDK.html

[Jason_Martin]

The flat figure eight is sketch.

 

To eliminate the possiblity of rolling an overhand flat knot (Euro Death Knot), the best thing to do is to tie two of them. Then it simply cannot roll.

 

Instead of tying two flat knots, some people will tie a single overhand into one tail of the rope near the end. The Euro Death Knot is on the inside and cannot roll over this single overhand.

 

I use the double overhand flat knot both in my cordelletes and in my double rope rappels. As of yet I have never seen anything sketchy.

 

I have joined an 8 milimeter rope to a 10 and have not seen a problem. I don't have any research to indicate where one should draw the line. My suggestion is that if you are concerned about the diameters of two ropes the default should be the double-fishermans.

 

Jason

[catbirdseat]

The flat figure eight is sketch.

 

To eliminate the possiblity of rolling an overhand flat knot (Euro Death Knot), the best thing to do is to tie two of them. Then it simply cannot roll.

 

Instead of tying two flat knots, some people will tie a single overhand into one tail of the rope near the end. The Euro Death Knot is on the inside and cannot roll over this single overhand.

 

I use the double overhand flat knot both in my cordelletes and in my double rope rappels. As of yet I have never seen anything sketchy.

 

I have joined an 8 milimeter rope to a 10 and have not seen a problem. I don't have any research to indicate where one should draw the line. My suggestion is that if you are concerned about the diameters of two ropes the default should be the double-fishermans.

 

Jason

Why use the knot in your cordellettes? What is the advantage over the double fisherman?

[Cobra_Commander]

you can untie them easily so you can use the cordellete for other things.

[mattp]

The EDK is not exactly the same as an overhand with long tails. The "EDK" is not a follow-through knot like what I believe folks in this thread are calling "overhand" (it is also called a "water knot"). In the EDK, the two tails are on the same side of the knot, rather than on opposite sides.

 

Water Knot, commonly used to tie runners and rappel slings:

 

 

 

 

 

 

Euro Death Knot, commonly used to tie rappel ropes together:

 

 

I have never seen the EDK "flip." Has anybody here ever experienced that? I only use it for tying ropes to rappel, so the loads are generally relatively small and I assume that more than body weight plus a little bouncing must be needed to make it flip.

 

 

[Gary_Yngve]

How often do you find yourself untying your cordalette for other purposes?

 

 

For the double overhand knot in a cordalette, I assume you're not using the 5-5.5mm tech cords (that are slippery enough to require triple fisherman)?

[Cobra_Commander]

Personally I like the feel of 6mm perlon for cordelettes. It ties well, it's strong enough, and it's dirt cheap.

 

Never seen an EDK flip, but I like some overhands on the tails of the knot, as weighting and unweighting seem to shorten the tails. I think it's important to have long tails on any EDK.

 

Gary, yes it is rare to untie a cordelette for rescue or hauling purposes, but it's nice to be able to do so easily when you want to. The fisherman's after it has been weighted after a season of climbing can be a pain to undo in the cold, etc. I don't think it matters that much, but the AMGA says to tie 'em that way so there's that, if you are into the guidy tricks.

[mattp]

I first learned to use and appreciate the EDK when climbing in - you guessed it - Europe. My German partner said the German Alpinverren Norm was 30 cm tails on your EDK used for rappel ropes. They were even using it for rappel slings, where we exclusively use the water knot and where I see no advantage in the EDK.

[Gary_Yngve]

I'd call 6mm perlon marginal. It wil generally have a strength of around 7 kN, whereas 7mm is 10 kN. (Different brands may be +/- 1 kN.)

 

A double strand is twice as strong, but one of those double strands as a knot, which will chop some percentage (40%?) off the strength, meaning about 8 kN for 6mm or 11 kN for 7mm could cause failure.

[Jason_Martin]

I was refferring to the second picture in Matt's post as an Overhand Flat Knot or an EDK.

 

I tie my cordellettes together with this knot in order to untie them quickly and easily. I untie them a lot. There are a couple of reasons I do this.

 

First, I untie them in order to tie figure-eight knots in the ends. I can then clip the ends into side pieces of an anchor and use the cordellete as a webolette by pulling down the strands in between the pieces and tying it off with an eight.

 

Second, I climb in areas where there are not always a lot of slings left behind. Or I don't trust the webbing that has been left. For example, I climb in Red Rock most of the winter season. When I get here much of the webbing on the classic routes has serious sun damage from the summer heat. I will cut up my cordelletes to replace what needs to be replaced.

 

Third, as a climbing guide I often short rope clients with an open cordellete.

 

Fourth, there are a number of rock rescue techniques wherein I need more cordage than a closed cordellete will allow.

 

Lastly, I primarily use seven millimeter cord for my cordelletes. Nothing seems to move within the knot when I use my double overhand flat knots.

 

I think that covers it...

 

Jason

[catbirdseat]

I was refferring to the second picture in Matt's post as an Overhand Flat Knot or an EDK.

 

I tie my cordellettes together with this knot in order to untie them quickly and easily. I untie them a lot. There are a couple of reasons I do this.

 

First, I untie them in order to tie figure-eight knots in the ends. I can then clip the ends into side pieces of an anchor and use the cordellete as a webolette by pulling down the strands in between the pieces and tying it off with an eight.

 

Second, I climb in areas where there are not always a lot of slings left behind. Or I don't trust the webbing that has been left. For example, I climb in Red Rock most of the winter season. When I get here much of the webbing on the classic routes has serious sun damage from the summer heat. I will cut up my cordelletes to replace what needs to be replaced.

 

Third, as a climbing guide I often short rope clients with an open cordellete.

 

Fourth, there are a number of rock rescue techniques wherein I need more cordage than a closed cordellete will allow.

 

Lastly, I primarily use seven millimeter cord for my cordelletes. Nothing seems to move within the knot when I use my double overhand flat knots.

 

I think that covers it...

 

Jason

It goes without saying that one should use the triple fishermans when using Tech cord (5.5 mm Spectra or Technora core). EDK is fine for 6 mm or 7 mm perlon (Nylon) cord.

[snoboy]

They were even using it [EDK] for rappel slings, where we exclusively use the water knot and where I see no advantage in the EDK.

 

Speed??

 

BTW I use the single fishermans on all my cordalettes. I feel it's a good compromise.

[layton]

anyone that's ever logged lots of time rappin' in Red Rocks, knows the reason for chosing the EDK above all else. The knot faces out and doesn't get trapped in cracks as easily. Therefor it is the safest knot to use and I get grumpy when my partner won't rap on it.

[EWolfe]

Never had any problem with slippage in 18 years of climbing. I lock the knot hard from the bitter end, usually.

[fenderfour]

I've seen another way to join ropes for rappel - Tie a square knot with long tails. Use the tails to tie a double fisherman's bend. The load is on the square knot which is easy to untie, but it's backed up by a double-fish. It takes a little longer to tie, but it works.

 

I still prefer the EDK.

[catbirdseat]

I've seen another way to join ropes for rappel - Tie a square knot with long tails. Use the tails to tie a double fisherman's bend. The load is on the square knot which is easy to untie, but it's backed up by a double-fish. It takes a little longer to tie, but it works.

 

I still prefer the EDK.

Yes, easy to untie but without the advantage of being less prone to hanging up, like the EDK.

[Ireneo_Funes]

I think that square knot/double fisherman's sounds like the worst possible combination for getting hung up.

 

The only thing I use the square knot for is joining the ends on a rope-backpack. Anyone here use it for anything technical?

[Dru]

Tyin' your mom to the bed

[Ireneo_Funes]

I'll ignore the obvious insult to my saintly mother to point out that tying your lady to the bed...IS AID!