Lazy Jacks

Mar 18, 2012
1
Recently went from a Dutchman system to a Sail Pac and Lazy Jack system. The installer attached the upper lazy jack lines to the middle of my top spreaders on pulleys for tightening and relaxing the lines during sailing. After 3 times out my port side spreader broke the casting at the pin hole. At my marina all boats have their top line attached to the mast up high... Was the spreader the wrong place to attach the pulleys/lines ?? Thoughts.
 
Jan 7, 2011
1,468
Oday 322 East Chicago, IN
Mine are mounted above the spreaders, but on the mast.

Some people mount them out a way on the spreader to keep the sail from catching on the way up the mast.

E87F8ABB-4B76-47E6-99E2-A54BD9DF93F8.jpeg
 
Jan 11, 2014
4,061
Sabre 362 113 Fair Haven, NY
Mine are mounted on the mast just below the lowest spreader. The line comes down to a cleat on the mast to allow the LJs to be pulled back to the mast while sailing.
 
Jan 11, 2014
4,061
Sabre 362 113 Fair Haven, NY
Recently went from a Dutchman system to a Sail Pac and Lazy Jack system. The installer attached the upper lazy jack lines to the middle of my top spreaders on pulleys for tightening and relaxing the lines during sailing. After 3 times out my port side spreader broke the casting at the pin hole. At my marina all boats have their top line attached to the mast up high... Was the spreader the wrong place to attach the pulleys/lines ?? Thoughts.
What kind of boat do you have?

Spreaders are in compression, i.e., the pressure on the spreaders is towards the mast, not towards the deck. If there down ward pressure from the lazy jacks that would put force on the spreader in a way that it is not designed to take, which might cause it to crack. There are other factors that might also contribute to cracking.
 
Jan 22, 2008
7,041
Beneteau 323 Annapolis MD
On my B323 I changed the lazy jack arrangement to adjust them from the cockpit. In the OEM holes in the spreaders, I put twisted D shckles and ran the LJs through those to take some load off the spreaders. The LJs go above the spreaders up the mast to turning exit blocks so they come down INSIDE the mast and to the cockpit. I can loosen the front lazy jack and take it out to a halyard cleat on the each shroud. This holds the bag WIDE open for catching the lowering sail.
 
Jan 19, 2010
211
Catalina Catalina 34 Casco Bay
My lines are mast mounted about half way between the spreaders and the mast head. At a spot about 2' below the spreaders there are blocks on each line. The blocks support a line that has a brass clip on each end. One end clips to a strap on the aft end of the stack pack. The forward end of the line has a figure of eight loop ( eye) 2' from the hook. The line with hook passes through the forward strap and snaps onto the loop when the sail is stowed. Prior to hoisting the main the clip is released from the loop and captures the line just below the loop and slides down. This provides the necessary slack in the system to allow the main to hoist without issue and not contain the main while sailing.
 
Jul 24, 2005
1,706
Beneteau 323 Manistee, MI
I would never have used the spreaders to take the load of the lazy bag with the sail in it. What happens is that when you hoist the bag around the sail to zip it up you are putting the most load on the spreaders, even more so if the sail got wet and you were just trying to cradle it without zipping the bag.

The further out on the spreaders those blocks are, the more down force bending moment you place on them. The spreaders on my boat have ferrules in them about a foot outboard of the mast and blocks attached to the mast about six feet above the spreaders. The lazy jack lines are threaded through the spreaders, up to the blocks, and down the sides of the mast where the lines are cleated just below the boom. This allows a fairly straight line upward, and a throat opening wide enough to contain the sail.
 
Oct 24, 2010
344
Solina 27 Wabamun, Alberta
My lazyjacks/lazybag control blocks are mounted on the mast above the spreaders, about 3/4 mast height.
 
Oct 22, 2014
9,983
CAL 35 Cruiser Portland OR, moored EVERETT WA
control blocks are mounted on the mast above the spreaders, about 3/4 mast height.
Why so high on the mast? Would not they work just as easily if mounted at the spreader height?
 
Jul 24, 2005
1,706
Beneteau 323 Manistee, MI
Why so high on the mast? Would not they work just as easily if mounted at the spreader height?
I thought about that. My feeble explanation is that it straightens out the angle from the spreader hole to the block on the mast which reduces the friction and wear on the line to a degree as well as the amount of downward force on the spreader.
 
Oct 22, 2014
9,983
CAL 35 Cruiser Portland OR, moored EVERETT WA
downward force on the spreader.
I was thinking of avoiding that by attaching the LJ's to the mast just below the spreader. Mast sturdy, spreaders not so much. Intent is to use the jacks to capture the sail as it is falling, Tie sail with sail ties to boom. No more need for lazy jacks, let slack and draw up along the boom.

Is that not how they work? Then when I need to raise the sail, I remove the straps and haul up the sail while pointed into the wind.
 
Jan 7, 2011
1,468
Oday 322 East Chicago, IN
I purchased and installed a Mack Sails Mack Pack with integrated lazy jacks, and their instructions were to mount the blocks above the spreaders, about 3/4 up the mast.
 
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Mar 26, 2011
2,373
Corsair F-24 MK I Deale, MD
The answer is in the first post. This doesn't always happen, but attaching lazy jacks to the spreaders has always been a known risk factor. This experience is just one more data point.

There is quite a bit of force when the lazy jacks are snug and the sail bellies out or is eased. I've snapped the line before when badly waked while preparing to lower sail (cruising cat).
 
Aug 28, 2015
165
Oday 28 St Joseph, MI
My lazy jacks are attached to the mast below the spreader and are led to the cockpit. Prior to leaving the slip I remove the sail cover, raise the jacks and remove all the sail ties except that farthest aft. When raising the sail I pull the jacks down, snug against the boom, and then there is no problem of battens catching the jack lines.
 
Jan 11, 2014
4,061
Sabre 362 113 Fair Haven, NY
I was thinking of avoiding that by attaching the LJ's to the mast just below the spreader. Mast sturdy, spreaders not so much. Intent is to use the jacks to capture the sail as it is falling, Tie sail with sail ties to boom. No more need for lazy jacks, let slack and draw up along the boom.

Is that not how they work? Then when I need to raise the sail, I remove the straps and haul up the sail while pointed into the wind.
John, that's how my lazy jack is rigged. It is 5/16" dacron spliced on to SS rings. The diagonals are spliced to eye straps on the bottom of the boom. We have a couple of shock cords on the mast that keep the LJ close to the boom when sailing.

The only issue we have is the LJs are more or less permanently attached to the boom and our mast comes down every year, so it is necessary to run messenger lines up the mast to rig the LJs, which most years works just fine, obviously not this year. But that's OK, since we don't yet have our new main. :(

The LJs came this way, if I was to do it again, I would use dynemma and low friction blocks and find a way to leave the LJ halyards attached to the boom.

IMG_1788.jpg
 
Oct 22, 2014
9,983
CAL 35 Cruiser Portland OR, moored EVERETT WA
That sounds pretty much how I have mine planned, with the help and design of @Hayden Watson.
All materials are on the boat. Next tasks is install. Thank guys for all your insight. The sharing of ideas is what I find this forum is all about.
 
Jun 27, 2014
112
Jeanneau Moorings International 50 Everett
My factory lazy jacks go up inside the mast and exit a few feet above the top spreader. They then route through ferrules in the top spreader about a foot from the the mast to open the lazy jacks wider than they would be just from the mast. On the way down to the cradle cover, they split twice (3 2 inch stainless rings) and attach to the cradle cover in 4 places. There is a separate line for the front of the cradle cover that is all external, just goes from the front corner of the cover through a stainless strap on the mast and down to a cleat. I leave that one looser until the cover is zipped up.
P1000621.JPG
 
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Jul 7, 2004
5,856
Hunter 30T Cheney, KS
Did the installer not follow manuf instructions?

I've had lazyjacks. I'm sticking with my Dutchman. I can saddle a sailcover over it ;)
The bag is nice though if you have a huge mainsail. I've never asked how furling main owners like their setup.