HR shackles can explode

[admiralslater]

I am very interested in the alloy portion of the conversation . As for undersized gear , my Outremer 45 has Harken 44 winches which I believe are under sized . I use the same winch on my Pdq 36

[funjohnson]

Originally Posted by admiralslater

I am very interested in the alloy portion of the conversation . As for undersized gear , my Outremer 45 has Harken 44 winches which I believe are under sized . I use the same winch on my Pdq 36

Sounds like you should just sell me the 45 (for the price of a 40) and I'll deal with the undersized winches

Matt

[fxykty]

Originally Posted by admiralslater

I am very interested in the alloy portion of the conversation . As for undersized gear , my Outremer 45 has Harken 44 winches which I believe are under sized . I use the same winch on my Pdq 36

Do you find the winches not powerful enough for any purpose? If so, can you add purchase rather than increasing winch size?

Our 55 with an 80sqm mainsail has 53 primaries and that’s plenty for every load. Note that our main sheet is 4:1, and daggerboards, running backstay, self-tacking jib sheet, main halyard and gennaker halyard are all 2:1. That certainly reduces the need for larger winches. On the mast we have a 48 on one side and we tend to avoid that one when hoisting someone up the mast.

[s/v Jedi]

Originally Posted by fxykty

Correct, the photo shows the standard block. It was the only one I could find of the perimeter setup.

For Dyneema or UHMWPE generically you don’t need the ring to turn - the slipperiness of the line plus the large radius reduces the friction for short high load applications. I will test this with my runners and report back.

The use of a block to keep the anchor line(s) from squeezing the ring and creating a soft axle is a good one and is basically the Ino-Rope solution. But then you do have to keep a close eye on wear of the soft axle and replacement according to Ino-Rope is 10,000 miles. If the ring remains static then you don’t have that issue.

Correct but then it is the runner tail that will need to be replaced and the friction is much higher. It’s simple to try just stick a piece of Dyneema through or around a ring and feel how it moves. The friction is like 10 times higher when you move it around a static ring compared to one turning. For a running back stay it’s probably okay... we use the runners more for mast trim (we have no back stays) and probably put more tension on them.

[s/v Jedi]

Originally Posted by admiralslater

I am very interested in the alloy portion of the conversation . As for undersized gear , my Outremer 45 has Harken 44 winches which I believe are under sized . I use the same winch on my Pdq 36

The winch strength of pull is mostly the same with a bigger winch; the difference is the speed with which it can pull the line in. Example: a bigger winch bringers quicker jib tacking but can’t lift a heavier load.

[Tillsbury]

Originally Posted by s/v Jedi

The winch strength of pull is mostly the same with a bigger winch; the difference is the speed with which it can pull the line in. Example: a bigger winch bringers quicker jib tacking but can’t lift a heavier load.

I thought the exact opposite was true. The number on a winch is the distance you move a winch handle to get a unit length movement of the rope, in the lowest gear. That’s directly linked to the force you can exert on the line.

[Breaking Waves]

for a highly loaded 180 degree turn . . . the only 'proper' solution is a high diameter (compare to the line) rotating sheave.

The Vendee boats use a lot of rings in various places, but they use rotating sheaves in their runners. I was just recently looking at this (3:1): . . . .



BUT . . .

rings with the moving part thru the center are in fact quite widely used in applications like vang tackles and runners, and they work, and are simple and inexpensive (more so that the 'proper solution'). The trade-off depends on how often you actually adjust them under load. . . if often then you will need to change the line more often which can be expensive in the end, but if not very frequently then there is little downside.

[Boatguy30]

Most modern winches have the model number as the max advantage ratio. IE, a 40 is 40:1 with a 10" winch handle.

[Breaking Waves]

“Winch numbering relates to the power ratio of the winch. That is the highest gear ratio multiplied by the length of the winch handle over the radius of the drum plus half the rope diameter. That means that on a size 48 winch turning a winch handle through 48 inches of arc will pull the rope in by 1 inch.”

[Pauls]

Jedi, thanks for posting that detail about the rotating ring. That's a good thing to know. I'm going to use it on my runners.

[double u]

Originally Posted by s/v Jedi

The winch strength of pull is mostly the same with a bigger winch; the difference is the speed with which it can pull the line in. Example: a bigger winch bringers quicker jib tacking but can’t lift a heavier load.

Thank you for this gem of wisdom...(why do you write about something you obviously do not have the faintest clew about?)

[s/v Jedi]

Originally Posted by double u

Thank you for this gem of wisdom...(why do you write about something you obviously do not have the faintest clew about?)

But I do have a clew and I haul it in with my winch

I was wrong because I thought from my cockpit using my electric winches. My Lewmar 66 pulls in more sheet per second than my 54 but it stalls out at the same weight. With the winch handle, the 66 has a noticeable higher power ratio.

[jmh2002]

I can add a couple of simple points from my own experience and perspective, but can't really back it up with exact statistics or facts directly related to your situation.

But I would say:

- You have a high performance boat. For it's time your generation of Outremer is, relatively speaking, somewhat of a racing boat, with an interior. It's quite far away from many of the normal cruising boats here.

- Deck gear wears out on these types of boats, so after 10 years or so (and how many miles at sea?) it doesn't seem entirely unreasonable that parts need replacing, even if it is not the normal understanding for some other cruisers or cruising boats here.

- Rightly or wrongly age wise, the shackles are showing clear signs of degradation. On a more performance orientated boat this needs more monitoring than an average cruising boat where there may be an expectation that such metal parts should last forever (even if this might be unrealistic too).

- I'm a Harken fan in general, and from a performance background. And what I will add is anecdotal, but from personal racing experience, not hearsay from the yachtie bar.

- In the past I often did not have confidence in off the shelf Harken shackles. I felt that the correctly specified blocks were up to the task (and they never failed), but that the accompanying shackles were not, and I normally replaced all the Harken supplied shackles with Wichard HR shackles.

- Thereafter we didn't have any shackle failures, but signs of degradation over time could still sometimes be seen in some specific and very high load locations. And this was most often in a metal to metal connection. Adding a 'soft' intermediate part normally resolved this. So you could somehow say that this was 'chafe' related.

NB: when I state 'correctly sized' I am speaking from a performance point of view and this suggests something lighter than 'cruising sized' which may have the expectation of never degrading or wearing out.

NB: this was at a time when soft shackles were coming into use (on racing boats) but entirely metal free connections weren't completely common yet.

Now there are many more options to help resolve these types of problems.

Just my 2 cents

[jmh2002]

Just for interest sake, this 'block' popped up in my news feed recently - a combination of a ring and sheave sides (which they are calling a spacer).

https://www.sail-world.com/news/223967/?source=rss

[fxykty]

Originally Posted by jmh2002

Just for interest sake, this 'block' popped up in my news feed recently - a combination of a ring and sheave sides (which they are calling a spacer).



https://www.sail-world.com/news/223967/?source=rss

That’s the Ino-Ending block from Ino-Rope. It is designed to be spliced into the end of a backstay to set up a 2:1 purchase. Seriously nice piece of kit.

The low friction ring plus spacer block that Jedi (I think) pictured earlier does the same job and for a fraction of the price.

A guy at Colligo I spoke with regarding using their static blocks says they’ve just designed and will soon produce a similar product, but it will be static.