UKH

Are there any issues using a water knot on 8mm dynema to re-sling a cam? Or, is there a better option?

Have a read of this thread from a while back: https://www.ukhillwalking.com/forums/gear/tying_dyneema_tape_into_a_sling-6069...

I'm pretty sure that a water knot in dyneema tape is not a good idea, but someone will be along in a minute to say it's fine.  The joys of t'Interweb...

Yes, it's not secure.

I used stitched 6mm slings into my cams when they needed re-slinging, these can be pushed through and clipped double (like a thread) or pulled into a larksfoot type arrangement (sling never actually sits on itself) for a longer sling.

jk

Thanks both, thought I'd read somewhere that it was a bad idea with dynema.

The link in the other post is dead, but I'm guessing it originally pointed to this vid: https://dmmclimbing.com/Knowledge/March-2012/Knotting-Dyneema%C2%AE One of the many reasons I love DMM.  I was surprised by the results for wet and frozen slings... whenever climbing ice I always had 'I wonder how much strength my QDs and slings have lost now they're frozen' in the back of my mind. 

depend on the design of the cam, small section webbing can cause a wire loop to pinch.

https://eu.blackdiamondequipment.com/en_GB/qc-labreslinging-camalots-and-c3...

I resling my cams using sewn dyneema slings and a rethreaded bowline on a bight. Essentially same as larks footing the cams but with a knot to keep everthing in place. 

The knot is shown here:

http://www.outdoorfreunde.net/knoten/palstek-doppelt-gelegt

Just thread the bight that goes through the eye in step 4 also through the attachment point of the cam, and then loop it over both the cam and the knot in step 5.

The bight will need to be a bit longer than shown, but you should anyway dress the knot until it sits tightly against the cam.

CB

Can you upload a photo? I can't picture this, but it sounds unconventional at best!

What cams do you have?

If you have the older Friends or C4s without the thumb-loops, I'd suggest you buy the 30cm Mammut Contact slings and just thread them through the hole. I kept it all together on the carabiner with a rope-retainer as well,  so no hapless leaders using my gear try and extend them in any way.  

If your cams have thumb-loops then stick to getting them re-slung by the professionals. 

There's nothing unconventional about a bowline on the bight, it's a perfectly reasonable way to semi-permanently attach something to a loop of material. https://en.wikipedia.org/wiki/Bowline_on_a_bight

jk

Sorry, can't do, my cams are 500km away after being annexed by my daughter (and I did not have much use climbing sport or sandstone). I may be able to simulate something tonight.

Also, this is absolute standard at least for my climbing partners here in Germany, and I have also seen it in the US.

CB

edit: just to add, the continental bowline tie in is exactly the same knot, but is of course generated by rethreading.

If you use it for rethreading a cam, you have to use the method shown in my link for laying the knot on a bight of a closed loop. You therefore "flip" the first bight over the knot and cam so that the cam ends up threaded by the large sling at the end (which of course you make as small as possible during dressing).

Ok, thanks! I can see it now (I think) I missed the point that the tails themselves will also form a loop in the sling which can be clipped...

Clever idea

The 'tails' or more accurately the tail loop gets dressed down tight against the rest of the knot so it *can't* be clipped but is secured because the whole knot has been passed through the loop. Hard to describe but it boils down a sort of complicated larksfoot that never fully snugs down under load.

jk