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Jack 09-22-2009 08:16 AM

HM Attachments
 
It has been pretty quiet around the ol' SparTalk table lately.

At The recent Port Townsend Wooded Boat Festival, I had the pleasure of finally meeting Brion. After sitting through an hour of good education at a presentation he gave, I tagged along as Brion and the crew were busy getting a beautiful 40 something wooden boat ready to take off for the Pacific.
That were finishing up with a new staysail stay that was made from HM Dynex Dux. It was a pleasure to watch the crew go aloft and go about the business of rigging.
The whole weekend is a treat. Plenty of "eye candy" to keep the most die hard wood boat guy happy.
I wanted to throw out one something that some of you may not have seen. I cannot post photos here so I will give a link. For lack of a better name I call these "Soft Hanks" Colligo is calling the "softies"....
What I have found is they are able to replace the SS shackle in almost every place I can think of. It has been so nice to use it to attach sails at the head, and the tack. To attach blocks, sheets, you name it, I have tried it. So far so good. My most brutal test was 3 months on the hook acting as failed block on my anchor bridle. No wear that I could detect. A flattening of the rope, that you can massage back to life. But no gouged paint or loud banging!
Some of what I am doing is really trying to destruct the stuff ot see what it can take. It has been fun....!:eek:

http://tinyurl.com/m7orsv

csandys 09-22-2009 11:04 AM

I'm interested in the kind of knots to use. Bowlines seem to work lose. I use buntline hitches which work well, but are hard to untie. Rolling hitches seem to slip also.

I find the modified brummel makes an easy splice.

Jack 09-22-2009 11:33 AM

csandy,

do you mean what kind of knot to tie in HM rope? Brion and others advise to not use a knot in this stuff. It is so slick, the normal knots will just slip out. There is a really good write up by Brion in the "fairleads" section of this website. :eek:

davidsamuelson 09-23-2009 12:40 AM

knots
 
Hi Jack,
Back in January you were talking about these soft hanks and you said you tied stopper knots. What knot did you tie? Does/did it slip? Do you sew the knot? Just curious.
When I get my act together I'll send photos of my halyards with incorporated soft snap shackles, if that is what you could call them.
David

Jack 09-23-2009 06:59 AM

Hey David,
would be interesting to see what you have there. All of the softies I am using were built by Colligo. I seem to recall hearing the knots were set using a machine. I know the end is melted also by looking at them.
I did not get the name of the knot, but they published a know here that may be it:

http://www.colligomarine.com/docs/mi...topperKnot.pdf

davidsamuelson 09-24-2009 12:10 AM

knots
 
Thanks for that link Jack..
I have been using the oystermans stopper - it looks neater, more rounded like a crown, but even if it hasn't let go yet I am not filled with confidence in its integrity. I put a stitch in it for whatever thats worth.
I think I will change and go thrash it around when the rain stops.
David

Jack 09-26-2009 05:28 PM

Halyard Loop design? Any hope?
 
I worked on my photobucket today. Added some nice shots of cruising. I also added a bunch of captions. While doing this, I came to realize I had almost forgot about the "end of halyard loop" I was working on before I left Mexico.
I would like some fellow Spartalkiens to critique the halyard loop. It worked well until it didn't. it is a about half way thru the slide show.The knot slipped out of the loop. And the sail came down. It is not the same knot as is on the softies. I was able to do a quick lash with some small stuff, and it never failed...... Also, I never saw any damage, but the way the core pulled down on the cover...well....I did not like that part. Comments please!

http://tinyurl.com/ycbdfcw

SV Papillon 09-27-2009 10:39 PM

Lots of cool stuff. Not sure about the halyard loop though, you still are going to have a hand sewn or pressed ring and headboard on main so a aluminum or composite shackel seems to make more sense. Kinda like asking your deck crew to thow bowlines in the gilsons to the codend so they don't have to worry about getting wacked with a big gunnebo saftey hook. They would probably just stick with the hooks.
Jake

davidsamuelson 10-06-2009 02:05 AM

Soft snap shackle
 
Hi Jack,
I have finally taken a few pictures of my soft snap shackle idea; I have not tested it much so am waiting for you and all others participating in this forum to shoot it down. Any ideas on changes or improvements welcome.
I hope the pictures explain all. To open the shackle hold the whipping with one hand and pull the cord. Make sure the cord is long enough so if the eye/loop collapses by mistake you can remake it by pulling the cord.
David











Dan Lehman 10-06-2009 11:10 AM

Quote:

Originally Posted by davidsamuelson (Post 4802)
Hi Jack,
I have finally taken a few pictures of my soft snap shackle idea; I have not tested it much so am waiting for you and all others participating in this forum to shoot it down. Any ideas on changes or improvements welcome.
- - - - - - - - - - - -
[Jack wrote]
I would like some fellow SparTalkiens to critique the halyard loop. It worked well until it didn't. it is a about half way thru the slide show.The knot slipped out of the loop

It might be instructive to hear the reasonings that led each knot-designer
to the structures each wrought.

It will also be instructive to view two videos of some Amsteel 3/16" line
tried with different bowlines; issues with the hi-mod fibre cordage are of
slipping and bending (strength).
www.youtube.com/watch?v=ZFRQcExLA34
www.youtube.com/watch?v=Fy6Y2Xoo4Ak

Now, I'll guess that both inventors above want to somehow avoid "knots"
because of rumors of failure -- of rope slipping out, primarily. These rumors
have some truth, but are also of a limited domain of knots (as video-2 shows,
with a variation of the Water Bowline holding). Still, there is the issue of
knot strength (or why are you using hi-mod cordage?).

And one wants to be able to untie the attachments shown in this thread.

Critique of Jack's eye structure:
1) the loading is awkward at best on the material, pulling the core
up away from an enclosing cover;
2) the Dbl.Overhand (Strangle) stopper knot might not be all so secure
as some others (Ashley's Stopper (mis-named "Oysterman's" by him)
can show a general stopper-construction that could be more secure,
methinks :: effect a noose that nips the end).
3) it entails more splicing than seems worthwhile/necessary.

Critique of DS's eye structure:
4) this seems to address security but at the expense of strength
-- the tight bend in the S.Part spells weakness.
5) and I must invoke #2 here, also.
6) moreover, in this case, the stopper must be able to fit through
any tied-to opening (clew) ! (--in contrast to Jack's, which comes
after the small spliced eye & double-thick line goes through ...)

- - - - - - - - - - - - - - - - - - - - - - - - - - - -

Here's an idea that occurs to me, taking off on Jack's idea.

Make a small eye with the brummel-like back'n'forth tucking of the
end through the S.Part, leaving a long enough end to ...

tie off the eye after the eye is inserted between the one (or two?)
of the brummel tucks through the S.Part (which, yes, means that
these might need to be spaced by more than is usual, anticipating
this construction).

So, one reeves the doubled line of the small eye through the clew,
then tucks its end between the back'n'forth weavings of the S.Part
and end in the brummel'd part, and then
bring the extra-long tail through the eye,
around the S.Part,
back through the eye,
... and finish as seems appropriate. One might even tie a stopper
in the end (ensure then that the small eye isn't TOO small for that).

Loading will scissors-pinch the brummel'd part around the inserted
eye, which cannot pull out because of the reeved tail holding it
in place. There will be two thicknesses of line through the clew,
sharing load/chafe/abrasion (and needing room).

There is yet a question of the awkwardness of this loading
at the point of the brummel -- so best at least that it be not the
one farthest from eye but closer to eye so that some sharing of
force has begun between tail & S.Part by time this tucked eye-end
intrudes upon them. Maybe tucking twice mitigates this well!?

--dl*
====

Jack 10-06-2009 12:24 PM

Looks like a good discussion. I am boarding a plane for Anappolis and will be there all week at the boat show. I will try to chime in if I can!:eek:

SV Papillon 10-12-2009 01:39 PM

Well??
 
I was flipping through a Harken catalog and saw something that had me retake the whole shackless halyard sheet thing. What caught my eye was the "soft" high load snatch blocks they have or more to the point the way the are attached. Using this approach to line attachment to sails seems like a very simple way to go. Essentially a loop of that passed through a keeper ring or strap and is made to a half round or round cleat. This should be relativly simple to incorporate into the head clew and tack of a sail. Then all you would need is a spliced eye on halyards sheets etc. The two down sides I could see would be having to convert all of your sails, and there could be a chance of it coming undone on a clew if the sail was flogging pretty badly. The attachment point could probably be made at a piece that bolts thru the ring in the sail catching the loop on one end and the cleat on the other with keeper loop stiched to the sail.

bottom of this page
Jake

Jack 10-15-2009 10:07 AM

Jake,

Those loops are made by New England I think, I talked to the head of the company about them. They sell to Harken and others. It is Dyneema SK-75 spliced in a loop/hoop like Brion shows in his book 5. They have a nice looking cover over it. Harken as well as many others are going to looped blocks. It all came out of the big round world race boats who were lashing blocks vs. shackles.
I just up loaded a bunch of photos to my URL and one shows the use of a softie on a boom block on the Westsail.......we renamed it the "Wireless Westsail"...check it out.:D

davidsamuelson 10-19-2009 06:05 PM

How much strength loss in a bend?
 
Hi,

To answer Dan's question of why I decided to make a hardware-free snap shackle, the answer, as is nearly always the case: necessity is the Mother of invention

I am currently 7° from the equator and that means no, or very light wind. My genoa is a normal cruising sail: stainless ring at the clew plus many extra layers of cloth to beef it up; in a word, heavy. Add to that 2 polyester lines with knots and sometimes some water and the weight is too much for the sail to have any shape.
Then a racing friend of mine was talking of removing his masthead tricolour light, plus wiring, to have less weight aloft. I suggested getting rid of his halyard snap shackle since that probably weighed more than the light. Hence the soft snap shackle.

Your criticism of my soft snap shackle Dan - well noted. ( He says "The tight bend on the standing part spells weakness") This bend is probably no tighter than the bend it makes at the clew of the sail so now I have 2 weak spots instead of just one; does this make it less strong?

How much strength is lost if a 5mm line is bent around itself?

Thanks, David

Jack 10-20-2009 09:12 AM

David, Removing running lights is radical surgury...... I had a Catamaran sailor tell me he uses a whip antennae on deck for his VHF because he figured the weight on the co-ax cable up the mast was no good.....:-)

I think the light air, or no air sailing is where I notice my lighter rig the most. After losing 40 lbs. off up high, the boat was much less prone to hobbyhorse, or jig back and forth on the swells/chop without the wind to hold the boat steady. It settles in quick and moves fwd. without shaking the little bit of wind out of the sails.

I had another guy tell me he spliced an eye in his sheets, and used a soft shackle to attach the headsail. It was lighter, and came across the for inside stays much better.

I use the soft shackle for tacks, headsail and mainsail attachments, and will be attaching the sheets soon.....:-)

Dan Lehman 10-24-2009 11:53 AM

Quote:

Originally Posted by davidsamuelson (Post 4822)
...
Add to that 2 polyester lines with knots and sometimes some water and the weight is too much for the sail to have any shape.
...
Your criticism of my soft snap shackle Dan - well noted. ( He says "The tight bend on the standing part spells weakness") This bend is probably no tighter than the bend it makes at the clew of the sail so now I have 2 weak spots instead of just one; does this make it less strong?
How much strength is lost if a 5mm line is bent around itself?
Thanks, David

I see that my thinking is going awkwardly between materials, here: the SK-75
in Jack's case, but PES in yours -- which makes a big difference in the effect
of sharp bends. But, in any case, I could even see some risk of your S.Part-tucked=
through-end structure leading on heavy loading to deformation of the end's split
around the S.Part, pulled wide out around itself, a loop/circle transforming into
a spiral, esp. on the side opposite the stopper. But even with PES (polyester),
I'm guessing 50% or so is lost, maybe more.
As for comparing with the hard turn around the clew, consider that the tension
on the eye legs should be half that in the S.Part, so even at equal *hurt* per
load, the load is halved, there. But metal typically is kinder to the fibres than
they are to themselves, re friction.

In composing the reply here, I'm also led to think of connecting soft eyes via
a soft shackle that is made of a double (even tripled) loop of material, the
ends just stoppered on opposite sides of the clew? -- doing so offloads much
force from these knots, which themselves stay oriented AT the clew and so
free of the connected eyes, and the bulk of the two (three) runs of material
give some extra bulk for the eyes to load and combined resistance to chafe?
-- of will this be a chafe situation only somewhat ameliorated, still bad enough
to discount?

But let me try to quickly put images to my earlier musing about a sort of
brummeling of an eye bight back through the brummels of a splice,
with the UNburied long tail used to toggle in place the eye tip, for easy
attachment/detachment to a clew. NB: what I present is done for a quick
proof (presentation) of concept; there might be a better implementation of
the idea, esp. re the brummel, where the "Mobius" one of having tucks
of both end & S.Part once will make for a better mechanism -- for now,
it's easy for me to just tuck the end both places, put in a Half-hitch on
redirecting the end back to make a single-strand toggle (I envision a
2nd pass but haven't the material at hand in this play rope).

The first image is slightly exploded to show the structure. Perhaps
there should be two tucks of the eye (hence, a 3rd brummel tuck) ?





--dl*
====


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