My First Soft Shackle

[cwyckham]

This is an amazing thread. Thank you, DH, SL, and Evans for a great read. You guys are a true brain trust.

[Dockhead]

Originally Posted by estarzinger

. . . And one solution that 'solves' both problems (capturing the ring, and making loop) is to make a loop that is long enough for full buries, and long enough to put twice around the ring (not buried just looped around twice), one of those loops is tightened up on the ring to capture it and is then just sew tacked (just a couple stitches each side) to the other portion (eg to the legs that leave the ring) to hold it tight. I guess I think this may be the 'best' solution. But, as I said above, did not do a ton of testing on it. . . .

OK -- so instead of burying the loop around the ring, you just loop it and tack sew it in place.

Why is this better than burying it like SWL did? Because the buried part in SWL's scheme may stress the fibers of the part in which it is buried?

I would have thought that SWL's method (which I think is really slick by the way, after finally understanding it) would be fine as long as the bury doesn't go too far around. My only question is whether it will continue to hold when the strop is not bearing a load.

[estarzinger]

Originally Posted by Dockhead

OK -- so instead of burying the loop around the ring, you just loop it and tack sew it in place.

Why is this better than burying it like SWL did? Because the buried part in SWL's scheme may stress the fibers of the part in which it is buried?

I would have thought that SWL's method (which I think is really slick by the way, after finally understanding it) would be fine as long as the bury doesn't go too far around. My only question is whether it will continue to hold when the strop is not bearing a load.

short story - I think its half a dozen either way.

longer story . . . I like the 'bury' method, it is pretty elegant and pretty easy . . . with only two relatively minor caveat:

(1) I am not a big fan of the grog join, and prefer a normal end-to-end, but that often leaves you with a longer sling than you would prefer (because of the bury/tapers), and I think you should then go to a multiple loop approach rather than try to shorten the buries. . . . When you go to multiple loops you can still use a bury on one loop to capture the ring, but you also have other options.

so that is really a caveat with the single loop/bury, not the bury as a concept to capture the ring

(2) Regarding the bury itself - I just did not do enough testing to be able to say for sure. There is a potential concern with the fibers being crushed under the bury (in the outer layer of the bury section). My best guess is that this is not a significant concern. But I just cannot say for sure. Sewing allows you to have the two strands side by side and not crushing or exiting.

Really the decision is a matter of whether you like sewing or burying better. I believe generally I am happier with sewing solutions than SL is (I'm about an equal toss up between them whereas I think SL much prefers spliced solutions).

As to your question about if the load comes off - well sewing will not loosen in that situation. You could do both - the bury and then just a quick tack to hold it tight in no-load situations . . . just as that is the preferred approach for the standard loop splice.

Probably the worst case with either of these 'second loop' solutions is if the ring somehow 'inverts', so the loop cross is now on the bottom rather than the top. Some work at the throat could prevent that.

If someone asked me to make one of these tomorrow . . . . I suspect I would combine a bunch of these solutions all together - multiple loops to have the best end to end join, the bury capture with a sewn tack to hold it tight, and a cover to neaten up the multiple loops, and a bit of decorative work at the throat to make sure the loops cannot invert off the top of the ring. That sounds like a lot but it really is not - probably quicker and easier than making a button stronger soft shackle. . . .and it would be pretty

Quick and dirty - the tight loop that pretty much all the commercial guys do is probably the answer. You may lose 20% strength with the throat angle but if that matters you just go up in size.

[Seaworthy Lass]

Originally Posted by Dockhead

I would have thought that SWL's method (which I think is really slick by the way, after finally understanding it) would be fine as long as the bury doesn't go too far around. My only question is whether it will continue to hold when the strop is not bearing a load.

The "capture bury", as Evans calls it, is extremely snug. Once tightened, I tried loosening it to increase the bury slightly (the buried portion always shrinks once the diameter increases with a bury and it ended up a bit small) and due to the curvature I had absolutely no hope. The bury will need to be cut away so I can reuse the ring. I doubt very much it will ever loosen when load is released. The issue of possible inversion when loose is one drawback though.

Dockhead, I would simply follow Evans' advice when it comes to making new strops for low friction rings. I have a fair bit of experience now both with making and using soft shackles over the last 2-3 years (and probably pushing them close to their SWL when they have been used to connect snubber to chain), but at the moment my thoughts regarding strops for low friction rings are simply ideas tossed about. I have used these rings racing back in Australia on a few boats the last couple of trips back, but that is the extent of my experience with them.

We have bought a few rings back to our boat this time, along with dyneema to experiment with them, but this is the first time I have played with making one. I have no access to load testing gear, which is very limiting .

Little knowledge is, however, sometimes very useful for tackling things with a fresh eye. With the "bury capture" of the ring, it was just the first thought that sprang to mind. The Grog sling appealed, as the bury needs to be so much less than for an end to end splice.

I think the ultimate strength of these strops for low friction rings (as well as soft shackles) is not the only consideration when picking a design. How easy a design is to use, any pitfalls with it (such as a possible inversion when loose), how it deteriorates with age (both strength and handling characteristics) and how easy it is to make can all be important factors. The best design many also vary according to the length required.

I doubt most of these strops are being used anywhere near their full safe working loads, so ultimate strength may indeed not even be the the most important thing. In addition, any loss in strength can usually easily be made up for by increasing the diameter of the line slightly.

Discussions like this and feedback following use helps tremendously with design improvements, so thanks for starting the thread . I am finding it extremely useful.

SWL

[Seaworthy Lass]

PS I should have included that for me, the amount of pleasure in making, handling and continually looking at a design to some degree also influences the decision of which one I go for .

[estarzinger]

Originally Posted by Seaworthy Lass

PS I should have included that for me, the amount of pleasure in making, handling and continually looking at a design to some degree also influences the decision of which one I go for .

The ones I like best aesthetically are with a nice throat whipping detail. A good place for two color paracord decorative work and that is an interesting different area of rope work to play around/learn with.

[estarzinger]

Another thought, away from the splicing sand box - seems like a very simple fabrication perhaps out of HMPE (cutting board plastic) would do an excellent job as a "throat clamp" for the ring.

Cut the plastic in a trapezoid, with the sides angled to create a 3:1 throat ratio, drill two holes thru parallel to the angled sides to take the dyneema line, make the top edge a bit curved to fit the ring snugly, need a way to fix it in place - perhaps either double dude tape to the ring or a needle or thread thru the dyneema (no load on it so no fear of stress riser).

You use this to fix the ring and then just need an end to end splice for the dyneema loop.

Would be a bit heavier and a bit less attractive that a two color paracord whipping . .. . But be easier for people with a simple hand tool skill set and less rope work skills.

[Seaworthy Lass]

Originally Posted by estarzinger

Another thought, away from the splicing sand box - seems like a very simple fabrication perhaps out of HMPE (cutting board plastic) would do an excellent job as a "throat clamp" for the ring.

Cut the plastic in a trapezoid, with the sides angled to create a 3:1 throat ratio, drill two holes thru parallel to the angled sides to take the dyneema line, make the top edge a bit curved to fit the ring snugly, need a way to fix it in place - perhaps either double dude tape to the ring or a needle or thread thru the dyneema (no load on it so no fear of stress riser).

You use this to fix the ring and then just need an end to end splice for the dyneema loop.

Would be a bit heavier and a bit less attractive that a two color paracord whipping . .. . But be easier for people with a simple hand tool skill set and less rope work skills.

Sacrilegious .

[Seaworthy Lass]

Originally Posted by estarzinger

.....
Probably the worst case with either of these 'second loop' solutions is if the ring somehow 'inverts', so the loop cross is now on the bottom rather than the top. Some work at the throat could prevent that.

The horrifying thought of plastic board and double sided tape on these strops has made me look at the "capture bury" again. Without a line passing through the low friction ring, an inversion could occur, but with a line threaded through I can't see how this is possible. I don't think any work at the throat is actually needed if a "capture bury" is used.

Phew, that eliminates the plastic .

SWL

[estarzinger]

Originally Posted by Seaworthy Lass

Sacrilegious .

ok, yea

I have to say after looking at a whole bunch of photos of top race programs friction ring set-ups - no-one in the 'real world' is concerned with throat angle.

The most common approach for 'higher strength' applications is both ends of the strop tight-eye-spliced to the ring - is a bit less than 2x the strength of the dyneema - which in most cases would be very strong, and it captures the ring in a way which cannot be inverted.

I one thing I realized - You mostly cow hitch in place - and the cow hitch probably about matches the strength loss of the tight eye splices - so they actually don't really create a system strength loss since the cow hitch already creates that loss. You would also need a full strength attachment (can be done - like running the strop thru a pad eye and splicing in place) to want to worry about the throat.

We have come up here with some very nice solutions that are more 'proper', but probably not more 'practical'.

[Seaworthy Lass]

Originally Posted by estarzinger

......
I one thing I realized - You mostly cow hitch in place - and the cow hitch probably about matches the strength loss of the tight eye splices - so they actually don't really create a system strength loss since the cow hitch already creates that loss. You would also need a full strength attachment (can be done - like running the strop thru a pad eye and splicing in place) to want to worry about the throat.

That is easy - just attach the strop with a soft shackle. It does lengthen it further, but this may not be an issue. It also means the strop can be moved without rethreading the line.

SWL

[estarzinger]

Originally Posted by Seaworthy Lass

That is easy - just attach the strop with a soft shackle. It does lengthen it further, but this may not be an issue. It also means the strop can be moved without rethreading the line.

SWL

agreed - but does add complexity - not so elegant. I guess I would prefer one size larger with just the cow hitch.

but I was going to add-on to the post above, that the main practical challenge I see in the photos without a 'standard' solution seems to be making a good 'short' (shorter than correct bury length) strop. And adding a soft shackle on does not help that problem. Conceptually you need multiple loops and there are various ways - the soft shackle itself is essentially a short multiple (2) loop solution, or simple lashings, or the various more complicated but more elegant things we have touched on above.

Finding the best ('proper' but practical) of these would seem to be the real challenge.

[Seaworthy Lass]

Evans, on our new boat we are substituting a conventional track and cars with an alu bar with holes as attachment points for low friction rings.

These need to be kept low to the deck. Removable rings are available commercially, but I have been considering the option of simply winding a soft shackle once around the ring. If is is made no larger than the minimum length needed, I think this would hold snuggly. Any thoughts?

SWL

[estarzinger]

Originally Posted by Seaworthy Lass

I have been considering the option of simply winding a soft shackle once around the ring.

SWL

photo or drawing please - not exactly sure what you are proposing.

[estarzinger]

This?