Low cost, high performance lazy jacks

Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
For years we have always saddle-bagged (large even flakes) the laminated mainsail on BlueJ's boom for storage. With 2 or more, this is an easy task due to the mast track and the full battens. No complaints, and it helps keep the main in great shape.

But there are times when I think about lazy jacks. I even have a Harken set somewhere in the house, I never installed them. Never because thought they were heavy, got in the way of the mainsail, and required mods to the sail cover.

But when I solo, or when we're just stopping for lunch on the hook or at a restaurant, I'd really miss them. And we've been doing more of that stuff lately. So I starting thinking about it more, and made a list of requirements.

Light weight
Totally and easily retractable for racing and covering
Do not interfere with racing or racing crew during sailing or maneuvers.
Minimal sail interference when sailing with them deployed
Removable (on/off)
Does not require cover modification
Simple and Hi-tech

The Harken set uses thick dacron line and blocks suspended in the air. I wanted to avoid all of that. So I stole some ideas from the Pogo 12.5, and made a set entirely out of dyneema and low friction ceramic rings. Oh and a half dozen eye pads.

41ACF687-4CCF-4A5F-8688-095823E36C77.jpeg


The top five feet on each side is 1/8 dyneema luggage tagged into pads 9 inches out on the spreaders. This trick helps keep the slot open when hoisting. The other end has a 7mm Antal ceramic ring spliced into a small loop. These rings hold the 'sling' of 5/64 dyneema that holds the sail. The sling starts luggage tagged to a pad 3 feet back from the gooseneck on port, goes up to the ring, down to a bail under the boom 3.5 feet (still optimizing position) from the clew, and up and down on starboard. Then to an eye and a cleat.

I went with a dual loop first, I think it will be OK. Even with the full battens the sail is about as big as you want to go with two. I have the option to mod it into a three loop system, but that complicates pulling it forward neatly.

The 5/64 dyneema has a breaking strength of 1000lbs. The weakest point of the whole thing is the rivets in tension on the spreaders. If I thought we would ever load those up with the jacks, I would move those to the mast and hold the upper part wide with shock cord.

Two more pads on the mast hold soft shackles that hold the whole thing captive when pulled forward. It also does not clang when retracted. It must weigh about 8oz, and is totally invisible against the sail. Total cost, 55 bucks? To celebrate I went for a solo sail, and in the middle of it dropped sail and anchored. Then sailed home!

25FFC18E-82FE-47EB-9400-5079BE2A3DED.jpeg
 
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Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
I like the idea and the materials selected. I have this on the project list now that I have the new main. It is open footed. It is slippery so while the folds at the mast are fine, they fall apart and go everywhere as it progresses aft.
 
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Jul 7, 2004
8,402
Hunter 30T Cheney, KS
I started to suggest Sail Care's Sail Cradle system but you have it figured out :thumbup:
 

JRT

.
Feb 14, 2017
2,039
Catalina 310 211 Lake Guntersville, AL
Cool, A couple of questions:

1) Did you consider a Dutchman system, if so why why not? I managed to break my mono filament lines and also not that my cover is not modified for it so I either need to fix the cover or always loose it at the end of the day and then adjust it to use it. I thought this was weird since I thought the idea was to set it and forget it. There is a really good chance I'm all messed up in what I'm doing also.

2) Would you consider this approach for a C310 Main if I decided I was tired of the Dtuchman and went this route? I never thought about spreaders before so would have to go up the mast or get someone to do it for me.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
I started to suggest Sail Care's Sail Cradle system but you have it figured out :thumbup:
Interesting, that kinda the same idea. Looks well thought out. But I don't think that can be left deployed when sailing. On cruising days I'll be perfectly happy leaving this out while we sail.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Cool, A couple of questions:

1) Did you consider a Dutchman system, if so why why not? I managed to break my mono filament lines and also not that my cover is not modified for it so I either need to fix the cover or always loose it at the end of the day and then adjust it to use it. I thought this was weird since I thought the idea was to set it and forget it. There is a really good chance I'm all messed up in what I'm doing also.

2) Would you consider this approach for a C310 Main if I decided I was tired of the Dtuchman and went this route? I never thought about spreaders before so would have to go up the mast or get someone to do it for me.
Not really a fan of Dutchman systems, I'm loathe to modify my mainsails like that, and I despise topping lifts.

Just sizing up the line and rings a bit and you'll be fine. As I noted the 40 foot Pogo 12.50 has a similar system, and that thing has a 600 sqr foot squaretop mainsail! That is impossible to manage without jacks.
 
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Apr 8, 2010
1,942
Ericson Yachts Olson 34 28400 Portland OR
There a lot of boats where the spreaders are held up by friction of the shroud against the end fittings. Some have an additional small "bull dog" clamp under the spreader tip. Some have very solid mast sockets that hold them in their "slightly above horizontal" alignment.
Some of them sag downward on their own, some are pulled down by too much tension on a flag halyard, and some will be pulled down by a lazy jack line.... lots of force potentially on a lazy jack, especially when someone pulls in the main sheet tight because the boom is swinging too far.
If you are careful and observant, that "spreader connection system" will work well and also have less chance of your lazy jacks fouling a batten. One mistake, tho, and you have a potential rig failure to deal with.
Be careful.
Ours are attached to the sides of the mast; it's just stronger.

Like Jack, I dislike the "Dutchman" scheme, and for the same reasons....

My .02 worth.
:)
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
Interesting, that kinda the same idea. Looks well thought out. But I don't think that can be left deployed when sailing. On cruising days I'll be perfectly happy leaving this out while we sail.
I had it on my Macgregor. It isn't designed to stay deployed while sailing. I modified mine so I could.
 
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Aug 2, 2005
1,155
Pearson 33-2 & Typhoon 18 Seneca Lake
Not really a fan of Dutchman systems, I'm loathe to modify my mainsails like that, and I despise topping lifts.

I have constructed lazy jacks in the past. Don't you need a topping lift to hold the boom up over the cockpit when the sail is lowered? If you do not, then the lazy jacks are supporting the boom I presume.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
There a lot of boats where the spreaders are held up by friction of the shroud against the end fittings. Some have an additional small "bull dog" clamp under the spreader tip. Some have very solid mast sockets that hold them in their "slightly above horizontal" alignment.
Some of them sag downward on their own, some are pulled down by too much tension on a flag halyard, and some will be pulled down by a lazy jack line.... lots of force potentially on a lazy jack, especially when someone pulls in the main sheet tight because the boom is swinging too far.
If you are careful and observant, that "spreader connection system" will work well and also have less chance of your lazy jacks fouling a batten. One mistake, tho, and you have a potential rig failure to deal with.
Be careful.
Ours are attached to the sides of the mast; it's just stronger.

Like Jack, I dislike the "Dutchman" scheme, and for the same reasons....

My .02 worth.
:)
Great point. On BlueJ (and now considered best-practice industry wide) the spreader tip is securely clamped onto the wire and will not move under any circumstance barring failure. I did think about the mast attach as well. But the stainless steel 'boomerang' that acts as the mast/spreader internal support runs 8 inches down the spreader, adding more support.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
have constructed lazy jacks in the past. Don't you need a topping lift to hold the boom up over the cockpit when the sail is lowered? If you do not, then the lazy jacks are supporting the boom I presume
Possibly, but not if you have a rigid vang or a boomkicker (like I do; see pic) that holds up the boom and sail.
 
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DArcy

.
Feb 11, 2017
1,691
Islander Freeport 36 Ottawa
The C&C115 I race on has a pretty heavy main which can be a handful coming down. The owner came up with a novel approach to lazy jacks that I've never seen before. The lazy jacks themselves are fairly standard with a 3 point attachment on the boom and a bridle raised by one ring. The difference is the top ring is held up by the spinnaker halyards rather than a dedicated line. To deploy, we run the spinnaker halyards between the upper and lower shrouds, so the lower shrouds hold them about half way out the lower spreaders. When the halyards are raised, the lazy jacks work just like normal. When lowered, there is a loop in the lazy jacks that is positioned to be run aft along the boom and hooked onto a bungy cord to tighten them and keep them out of the way.
Without any hardware on the mast, no changes required to the sail cover, and no additional cordage aloft, the lazy jacks act just like traditional, widely space lazy jacks.
 
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Jun 14, 2010
2,081
Robertson & Caine 2017 Leopard 40 CT
There a lot of boats where the spreaders are held up by friction of the shroud against the end fittings. Some have an additional small "bull dog" clamp under the spreader tip. Some have very solid mast sockets that hold them in their "slightly above horizontal" alignment.
snip
:)
@Jackdaw If you have a setup such as I highlighted in red above, and your spreaders are well anchored, then I recommend you move the lazyjack spreader attachment further outboard from the mast approximately midway, then the jacklines won't bother your sail as much and no need to pull them forward. Also, move your eye to the top of the spreader and wrap your upper attachment around the entire spreader (so the eye is only needed to keep the line in place horizontally, and no tension on the eye rivets -- only minor shear loads).

PS -- There would be no concerns about overloading the lazyjacks if you adjust your lazyjacks to hold your boom to a lower position than the boom would be when the sail is fully hoisted.

Another edit: Good job!
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
@Jackdaw If you have a setup such as I highlighted in red above, and your spreaders are well anchored, then I recommend you move the lazyjack spreader attachment further outboard from the mast approximately midway, then the jacklines won't bother your sail as much and no need to pull them forward. Also, move your eye to the top of the spreader and wrap your upper attachment around the entire spreader (so the eye is only needed to keep the line in place horizontally, and no tension on the eye rivets -- only minor shear loads).

PS -- There would be no concerns about overloading the lazyjacks if you adjust your lazyjacks to hold your boom to a lower position than the boom would be when the sail is fully hoisted.

Another edit: Good job!
For sure, I could leave them out while sailing. The primary reason I pull them back is to put the cover on. If racing no need to bring them out because crew can flake the sail.

Ah clever! Wrap around the FRONT, I only thought about the sharp aft side. The front is airfoil smooth. Good idea.
 
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Jan 22, 2008
198
Montgomery 17, Venture of Newport, Mirror sailing dinghy, El Toro sailing dinghy Mound, MN -- Lake Minnetonka
This is an ad for a system marketed by North Sails back in the 1980s. I have been using a homemade copy on my 23’ cutter for about 40 years and on my Montgomery 17 for the last 5. No special luff slides, and I don’t use nearly as many leech lines as shown in the ad. I started out with just two, using the leech reef grommets as attachment points. This worked so well in automatically flaking the aft end of the sail and keeping it from spilling into the cockpit that I added several more grommets for additional control lines. The aft ends of the control lines are tied to small snap hooks that snap over the topping lift and slide up and down on it. Once set up this system needs no adjustment. You can raise or lower the sail easily even if you are not pointed directly into the wind. It overcomes all of the frustrations I had with the several variations of conventional lazy jacks that I had tried. YMMV, and it does require a topping lift.


image.jpg
 
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DougM

.
Jul 24, 2005
2,242
Beneteau 323 Manistee, MI
I like my lazy jack/lazy bag setup (I don’t race any more), because the way I have it set up I can drop the bag and secure it to the sides of the boom. The only problem that I have not solved is the chafing of the lazy jack lines where they are threaded through the spreaders. if I didn’t change those out every year, and one of them failed, it would mean a trip up the mast. At age 73 that is no longer appealing.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
This is an ad for a system marketed by North Sails back in the 1980s. I have been using a homemade copy on my 23’ cutter for about 40 years and on my Montgomery 17 for the last 5. No special luff slides, and I don’t use nearly as many leech lines as shown in the ad. I started out with just two, using the leech reef grommets as attachment points. This worked so well in automatically flaking the aft end of the sail and keeping it from spilling into the cockpit that I added several more grommets for additional control lines. The aft ends of the control lines are tied to small snap hooks that snap over the topping lift and slide up and down on it. Once set up this system needs no adjustment. You can raise or lower the sail easily even if you are not pointed directly into the wind. It overcomes all of the frustrations I had with the several variations of conventional lazy jacks that I had tried. YMMV, and it does require a topping lift.


View attachment 166225
Thats interesting, I remember that from back in the day. It must not have appealed to enough people for it continue as a product. It seems a bit 'busy' to me... what are the 'special slides' that force it to flake?? But I love the idea of flaking vs stacking. Our main loves to be flaked over the boom. Stacking, not so much. But the good part is we can flake it in the jacks before we put the cover on at the end of the sail.
 
Jan 22, 2008
198
Montgomery 17, Venture of Newport, Mirror sailing dinghy, El Toro sailing dinghy Mound, MN -- Lake Minnetonka
I don't know what the "special slides" were. I never saw the actual system in person. I just saw the ad and thought I could do something similar. It has worked well for me. A person could use just the two leech reef grommets for the leech lines to give partial control of the sail. While that would not affect the forward part of the main it would keep the aft end from spilling into the cockpit when dropped in a hurry. Perfect for singlehanding. Try it, you might like it. It doesn't cost anything other than a couple of pieces of scrap line.
 
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JRacer

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Aug 9, 2011
1,331
Beneteau 310 Cheney KS (Wichita)
Lazy Jacks in place with boom cover on. Boom Cover slotted vertically with zippers to accommodate. Underside of holes have flaps that cover the sail and zippers have flaps on the underside as well. Blow the pic up for a closer view.
Mast IMG_20170802_165710684.jpg
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Lazy Jacks in place with boom cover on. Boom Cover slotted vertically with zippers to accommodate. Underside of holes have flaps that cover the sail and zippers have flaps on the underside as well. Blow the pic up for a closer view.
View attachment 166256
For sure, this is by far the most common method of deployment for lazy jacks in the USA. In Europe they basically skipped this when went straight to lazy bags. I think I've seen one slitted cover in all my sailing in Europe.