Clutches are designed to hold highly loaded lines that can be hauled in and released with the aid of a winch. Choosing the proper clutch for a given application on a sailboat is determined by two main criteria: Line Diameter Maximum Line Load Holding Rating Additionally, there are other factors which can affect a clutches’ performance and influence which you may choose. In this article, we will walk you through how a clutch works, how to choose a clutch, and […]
Clutches are designed to hold highly loaded lines that can be hauled in and released with the aid of a winch. Choosing the proper clutch for a given application on a sailboat is determined by two main criteria:
- Line Diameter
- Maximum Line Load Holding Rating
Additionally, there are other factors which can affect a clutches’ performance and influence which you may choose. In this article, we will walk you through how a clutch works, how to choose a clutch, and how to mitigate potential performance robbing issues.
How to Operate a Clutch
A line running through the center of a clutch is cleated or held when the handle is closed. While closed, a clutch will allow you to haul in lines although this causes friction, making the task more difficult and reducing the life of the internal parts. Also, clutches will grip line better (more immediately) if they are eased closed on a loaded, stationary line. So ideally lines should be hauled in with the clutch open (handle cocked open). Once a line is completely hauled in, the clutch can then be closed to engage and hold the line optimally. The clutched line can then be removed from the winch, freeing the winch for other tasks.
To release a clutched line, fully load the line up on a winch first; otherwise, the line will ‘grate’ and abrade on the holding surface of the clutch upon release. Zero line movement when the clutch is released is ideal to preserve the cover on the line). Once open, ease out the line as desired using the winch.
NOTE: Although most major clutch manufacturers state that their clutches can be released under load, this should only be an emergency backup to property releasing a line. Emergency releases (unclutching under load) of a line from a clutch causes destructive stress to line covers. Repeated releases can literally tear the cover apart. The higher the line is loaded, the more possible damage to the cover. Always take the load fully up on a winch before opening a clutch if possible.
Jammers Verses Clutches
Jammers are also designed to hold highly loaded lines that are usually hauled in and released with the aid of a winch, but there are two main advantages to clutches over jammers. First, lines can be adjusted in, if need be, with the clutch closed, and the clutch will automatically hold the line when tension is released from the winch (still better for wear and tear reduction on the clutch parts and rope if you can adjust the line with the clutch open). Classic jammers require you to shut the jaw manually, after hauling the line in before taking the load off of the winch (Note: a few ‘new generation’ jammers will auto-engage). Secondly, jammers cannot be opened under load, and the load must first be taken off using a winch before you are able to open the jammer and release the line. In an emergency, fully loaded lines can be released from a clutch by simply opening the handle.
How Clutches Hold
The key to clutches holding a highly loaded line securely, and with no slip, is about maximizing the line holding surface area of the clutch that comes into contact with the line’s outer jacket. Second is the amount of friction the holding surface can generate, without damaging line.
Spinlock’s clutch uses a serrated aluminum cam that compresses the line against a serrated, slightly curved aluminum bottom plate.
Antal’s clutch uses a ‘V’ shaped serrated stainless cam that wraps partially around the line to engage more line surface area. It compresses the line against a curved, narrow, moderately serrated section of the bottom plate. This narrow strip is able to penetrate into the ‘V’ of the cam, to aid in encapsulating more of the line all the way around.
Lewmar’s clutch uses a series of ‘domino’ plates that the line runs through, which are pivoted forward, and down onto the line. This compresses the line, causing it to snake up and down, and through the plates, which locks the line. Because the line and its cover are being compressed over a larger/longer area, this type of clutch generates the least amount of cover wear.
Lines & Clutches
Considering Line Diameter when Choosing Clutches
Most clutches will have a range of line diameters they are designed to hold. If you take a clutch rated for line diameters from ¼” to ½”, the ½” line will provide the clutch substantially more surface area to ‘grip’, compared to the ¼” which is half the size/surface-area. The clutch will have a maximum holding load based on the larger ½” line. If you are using ¼” in the same clutch, you can expect a much lower holding load. Most clutches will lose between 25% – 60% of their holding ability as you move from their maximum line diameter rating to the smallest line diameter in their range.
Tip: When matching clutches to line diameter, be sure to choose a clutch where line diameter is at the top of the clutch’s designed diameter range to ensure no slip holding when the line is highly loaded.
Considering Line Types in Relation to Clutches
There are three basic categories of line when considering clutch performance:
- Classic double braid polyester
- Lines with high tech cores (Dyneema, Spectra, Technora, etc.) with polyester jackets
- Lines with high tech cores and high tech, abrasion resistant covers (Technora, PBO, Kevlar blended with polyester).
Classic double braid polyester
Low stretch double braid polyester lines were the first to be used in clutches. They were large in diameter (compared to high tech lines available today), so they presented ample surface area for clutches to hold.
Although these polyester lines are a low stretch line, they do have a lot of elastic stretch compared to today’s high tech lines – up to 4 or 5 times more. So, if a highly loaded polyester halyard were to slip one or two inches in the clutch, the elastic recovery of the line would make this virtually unnoticeable and would not substantially change the load on the line. Polyester lines are less demanding of clutches and perform well in them.
High tech core with Polyester Jacket
High tech cored lines with polyester jackets present the biggest holding challenges for clutches, and are the most prone to damage by them. These line types are by far the most popular performance line upgrade and can perform exceptionally well when spec’d, installed and used correctly.
High tech lines provide higher strength and lower stretch (recoverable elongation) than double braid polyesters. The higher strength means a halyard (or other control lines) can be of a smaller diameter (saves money, less weight aloft) than a polyester line doing the same job. This smaller diameter presents less surface area for the clutch to hold. So if you upgrade a halyard to a smaller diameter high tech line, clutch holding often becomes a new issue.
With Spinlock clutches, there is the ability to change out cams in their XAS, XTS, and XCS clutches that are optimized for the smaller diameter line. Antal clutches have the ability to change out the base plate in all of their V-Cam clutches to better hold smaller diameters lines too. Additionally, if the existing cam or baseplate serrations are worn, you should replace them with new to regain high holding load performance. For non-cam clutches, you may need to replace the entire clutch with one that is optimized for the new, small diameter line.
Line bulking adjustments
Another option is to add diameter to the line where it is clutched. This can be done with the addition of a second cover, or a core bulk splice:
Cover bulk splices take a larger diameter cover-only which is slid over the line area to be clutched. The ends of the second cover are tapered and buried back into the line’s existing cover. Note: Mainsail halyards – for reefing, this may need to be done in multiple locations.
Core Bulk splices take a Dyneema single braid and insert it in the high tech core of a line, which will intern increase its overall diameter. It’s preferred because it will not be affected by any core slip. The limiting factor for this splice is the tightness of the line’s existing cover. A few covers are so tight that this type of slice is not possible, Most lines will allow for a 1/8” core insert, while others with a looser woven cover, may accept a 5/32” or larger insert.
The second issue with this type of line material/construction is in the cover. This is especially true when racing, as lines are aggressively downsized, highly tensioned, and may not always be properly released from the clutch.
Double braid polyesters carry the line load in both the cover and the core, and both have equal stretch properties; so the cover stays attached to the core (stationary). High tech lines carry all of the load in the core, and the much less strong polyester cover struggles to stay attached to the core under load. When the cover slides on the core of a highly tensioned line in a clutch, this is interpreted as halyard stretch, or clutch slip. In reality, the cover is staying stationary in the clutch (not slipping), but the core is slipping inside the cover. This creates loss of line tension and creates huge stress on the cover, which is now bearing line load it was not designed for. Preventing cover slip is the key to performance and longevity with these types of lines.
If you think of the Chinese finger trap as the cover on a line, and your fingers as the core of the line… If the trap is wide and open, your fingers slide in and out easily (slip in and out). If you pre-tension the trap on your fingers, then the harder your pull, the more trapped your fingers are (and the trap holds your fingers without slipping). It is the same way with lines. If the cover is loose on the core, the core can slid through it and appear to be stretching when the clutch is closed. If the cover has all excess material ‘milked’ out of it (pre-tensioned) and has been properly seized at its end to keep it that way, the cover will more likely stay attached to the cover when clutched. After a break-in period with new halyards, it is not uncommon to experience the cover loosening, or bagging up. If this happens, cut off the seized bitter end of the line, and tie the working end of the line off to a strong fixed point. Then with gloves (we use sticky Nitrile gloves in the APS rigging shop) or a rag, you want to repeatedly pull the cover, under as much grip/tension as you can, down the entire length of the rope (from working-end to the bitter end). Once done, cut the excess cover away at the bitter end, and seize the end in place. This applies to cover bulk spices (second covers) too.
Lastly, to further aid in preventing cover slip (and help reduce cover chafe damage), for both racing and cruising sailors, treat lines with Spinlock’s RP25 in the area(s) that are clutched. The PR25 coating is a chemical with a low viscosity that penetrates the outer cover, coating all the fibers as it goes on into the core bonding the two together. This action not only assists in preventing cover-to-core slip by 10%, but also improves resistance to both internal and external abrasion by 40%. It is a simple process to apply, and highly recommended. It only needs to be applied in the clutched areas. For main halyards, you may need to apply it in multiple areas for clutching with reefs in.
So, polyester covers serves to protect the high tech cores, and make them grip-able, clutch-able and winch-able. Clutch manufactures walk a fine line with designs that are good at holding these lines (aggressive grip), while not abrading the cover. In fact, Antal states that these types of lines ‘prove to have poor resistance [to clutch generated abrasion]’. With this said, you should not be dissuaded from using these types of lines by any means. They are extremely popular, and great performers. The key is to make sure you follow best clutching and unclutching practices as mentioned earlier, and consider applying RP25 to the clutch areas.
Tip: to dramatically increase the life of polyester covered high tech lines, winch in lines with the clutch open, and always use a winch to fully unload the clutch before opening it.
Tip: order your halyard a few feet long. If it begins to show wear in the area that is clutched, pull the halyard from the mast, cut the halyard shackle off, have it spliced to the opposite end, and rerun the halyard. Presto, a like-new halyard in your clutch.
High tech core & cover
High tech cored lines with high tech abrasion resistant covers are designed to hold up to and perform well in clutches. Even at very high loads, and with the occasional loaded release from a clutch, they have substantial resistance to clutch wear. Due to the low stretch properties, and tightly woven construction, cover slip is not usually a major issue. As long as clutches used with them are properly matched, the only real downside is that they come at a substantially higher cost than other lines. For some high-performance race boats, this type of line may be the only choice for dependable performance. For cruisers, this type of line is not usually considered necessary.
Additionally, Spinlock has a ceramic coated cam and base plate upgrades for their XTS and XCS clutches (sold separately) that are designed specifically for these types of covers. They resist wear on the serrations and last longer, they have higher holding loads, but the largest benefit they offer is in the initial ‘take up amount.’ Once a line has been hauled in and the clutch closed, the load is eased off of the winch and transferred fully to the clutch. As this is done the line travels slightly back, to fully engage in the clutch (the take up amount). The ceramic parts do a far better job of reducing this distance, as they engage with the cover more quickly. This is substantial performance enhancement for racers who require highly loaded lines to stay fully loaded, and right where they set them.
Choosing Clutches – Line Diameter & Holding Load
Use the charts below to compare the line diameter ranges and maximum holding loads from clutch to clutch. If you line will be highly loaded, look for clutches with high holding loads (red) that show your line diameter at the top of the clutches’ diameter range (blue).
Clutches for Small Boats (27’ LOA and Below)
Clutches for Medium to Large Boats (28’ – 54’ LOA)
Clutches for Large Boats (50’+ LOA)
Cleaner Decks, Fewer Winches
If you have an older cruising boat with dedicated winches on the mast for halyards, boom for outhaul, and multiple deck top winches, you can greatly reduce the number of winches you have, and simplify your deck layout with these controls lead aft to the cockpit.
Having banks of clutches with deck organizers behind them will allow you to use two cabin top winches for all of your halyards and major control lines, and all of this from the safety of the cockpit. When purchasing double or triple banks of clutches, be sure you are clear on the line diameters they will be used with. You may mount a double clutch with a diameter range for your smaller control lines, and a bank of three clutches optimized for your large diameter halyards (or another combination that works for you line needs).
Tip: When re-leading lines aft, be sure to group like line diameters together such that they lead to clutch banks optimized for their diameter.
Winches on sailboats are powerful and compact internally gear driven tools that allow you to haul in and hold lines under high loads manually, by a single person. Winches will have their size stamped on the top of the drum, ex. 20, 35, 40, and so on. This number indicates the power ratio. For example – a #35 winch will provide a 35:1 mechanical advantage. Say you have a winch handle inserted into the top of the winch and you […]
Winches on sailboats are powerful and compact internally gear driven tools that allow you to haul in and hold lines under high loads manually, by a single person. Winches will have their size stamped on the top of the drum, ex. 20, 35, 40, and so on. This number indicates the power ratio. For example – a #35 winch will provide a 35:1 mechanical advantage. Say you have a winch handle inserted into the top of the winch and you are exerting 40 pounds of pressure as you wind the handle, which is, in turn, winching in a loaded line. The amount load being translated to the line is 35 x 40 = 1400 pounds. Impressive power.
So, you are the engine, the winch is the transmission, and the handle connects you. But what handle should you use to reduce fatigue, and that will be optimal for the load and available winching area?
We will take you through the four criteria to properly choose a sailboat winch handle:
- Locking versus non-locking
- Handle length
- Handle grips
Classic winch handles are either bronze or chromed bronze. They are beautiful (especially on a classic boat), built to last a lifetime, but heavy and the most expensive.
Anodized aluminum sailboat winch handles are medium weight, robust, and are by far the most popular on the market.
Reinforced plastic handles offer a lower price, lightweight (some float on or at the surface of the water), but extreme winching loads and can cause them to flex sometimes.
Carbon handles are lightweight (about half of the weight of aluminum), and without the possibility of flexing life plastic handles, but they carry a higher price tag.
Locking or Non-Locking?
Images courtesy of Harken
All modern winch handles use an 11/16″ (17.5 mm) octagonal star stud that fits into the top of the winch. Locking handles will have a spring loaded square lock-plate on the end of the star studs. When the spring-loaded lock-plate is held in the unlocked position, it aligns with the star stud ridges, allowing it to be inserted or removed from the winch top. When the lock is released with the handle in the winch, the plate rotates out of alignment with the star stud, and catches on the corresponding ridges of the winch, holding the handle securely into the winch.
There are two exceptions to the lock-plate: 1. The Harken OneTouch handles, which uses two stainless retracting pins. 2. The Ronstan Quick-Lock handles which has an auto-insert locking mechanism and is the only locking handle you can put in a winch without having to unlock it first. By sticking it into the winch it automatically locks until you depress the handle button to release it.
All lock types are actuated either by a thumb-operated lever (on top, or on the side of the handle) or by a top plate that is hand squeezed.
Generally, all handles on a boat should be locking unless there is a specific reason for it not to be. While non-locking handles are easier and faster to insert and remove from the winch, they are also easier to lose overboard if you don’t immediately remove it from a winch after use, and you knock it, or a line catches it. Losing handles overboard is expensive, and boats are extremely hard to sail if you run out of them.
The type of lock you choose is all personal preference. Top- thumb and side–thumb operated locks only require only the movement of your thumb to actuate the spring-loaded mechanism. Top-hand locks require you to grip the sides and underside only of the handle’s shaft so as not to unlock it and then squeeze the trigger with your thumb when you are ready to unlock it. Top thumb locks are easy to operate with your thumb, either right or left handed, and are the most commonly purchased handle, historically. Side thumb handles are easy to actuate left or right handed, and sleek on top (line shedding). Think through what would be easier for you and your crew to operate.
10″ handles are the most common and comfortable handle length for most sailors. It is the length that will give you the most power. When looking at specifications on winches, they will be based on this length handle.
8″ handles allow you to grind faster because they swing through a smaller circle, but power is reduced by about 20%. Cruisers may use them when a dodger or bimini is installed too close to a winch to use a 10” handle. They work well on smaller race boats when speed is more important than power. If you are a really strong person, and trimming substantial loads is not an issue, using these when racing on larger boats may be desirable, due to the faster trimming speeds.
All quality winch handles will have ball bearing grips to reduce friction and translate the maximum amount of your energy to the winch. Some handles can even be rebuilt with new bearings after substantial use, but this is a rare occurrence.
By far the most common grip type used and found on sailboats. If you do not have any specific needs of your handle other than for it to work well in a wide variety of uses, this is the default sailboat winch handle.
These are designed to help you translate two arm cranking power to the winch once the load is fully taken up by the winch. Initially you crank with one hand at high speed; then transition to two hands when the load becomes too much for just on arm. If you do not need the additional power of a double grip, consider a more appropriate handle. The taller grip stack will more easily snag lines (and body parts), and the larger size can be more difficult to store in a ready-to-use location.
Knob Grip Only:
Excellent for racing where maximizing winching speed is the only concern. The palm of the hand is placed on top and the fingers grip around the knob top. Once substantial load comes on, it is assumed you are done winching in, as you cannot switch to the more powerful vertical grip or two-handed grip on this low profile design.
Knob with Single Grip:
Allows you to change from speed grinding with your pam around the knob, to one-handed power grinding on the vertical grip when the load becomes substantial, or supper powered two-handed grinding with one hand on the knob and the other on the vertical grip. It’s almost like having a three-speed handle. The Haken is unique in that the knob and the single grip rotate independently of one another, thus allowing your wrists to bend independently when two-handed winching.
At the end of the day, if you have no special requirements of your winch handle, and you are looking to purchase a new one, a 10”, top thumb locking, aluminum, a single grip is a safe bet.
Electric Winch Handles
WinchRite Electric Handle
If you are looking to greatly reduce the physical strain of winching lines, this product allows you to effortlessly operate any manual winch by simply sticking the handle in the top and pulling the large button built into the grip. It is variable speed – starts off slow so there is no jolt. It is waterproof and also floats, and can be charged with the included AC or DC chargers. Battery life is said to be equivalent to hauling the main up 6-8 times on a 38’ boat. It even comes with a molded PVC bulkhead pocket for storage.
Cruiser Ingenuity, Electric Handle
It consists of a 24V angle drill (Milwaukee model 0721-21) with a winch ‘star bit’ (Harken). With the bit in the chuck of the drill, just drop it into the top of your winch with the drill set to low speed. Pull the variable speed trigger and you have electric winches. This is a less expensive solution than a purpose designed electric winch handle, but it does have some significant downsides: It’s not waterproof (needs to be stowed away in really wet conditions), does not float, not easy to store, and it’s almost twice as heavy as the WinchRite. Some who use these have created a waterproof and padded sleeve for the drill which helps address its lack of water resistance and helps protect deck gel coat.
As a side note, the Harken ‘star bit’ is sold as an emergency furling device for electric and hydraulic furlers. If there was furler power loss, you would put the bit in a cordless drill, and insert it into the side of the furling unit, and furl it with drill power.
Reaching Sail Furler Options for Cruising Sailboats Sails built for the sole purpose of reaching, or sailing off the wind, offer a range of powered up sailing for cruisers. Paired with a furler, these sails are easy to handle and maximize your boat speed (especially in light air). The two types of furlers for cruising reaching sails are: Bottom up furlers for straight luffed Cruising Code 0 sails Top down furlers for free flying a-symmetrical spinnakers SHOP ALL FURLERS Advantages […]
Reaching Sail Furler Options for Cruising Sailboats
Sails built for the sole purpose of reaching, or sailing off the wind, offer a range of powered up sailing for cruisers. Paired with a furler, these sails are easy to handle and maximize your boat speed (especially in light air).
The two types of furlers for cruising reaching sails are:
- Bottom up furlers for straight luffed Cruising Code 0 sails
- Top down furlers for free flying a-symmetrical spinnakers
Advantages of Furling Reaching Sails
Furling reaching sails allow you to store sails rolled on their flexible furlers below decks. They can be easily and quickly rigged on deck, have continuous furling drums/lines for trouble-free furling and unfurling once they are hoisted on the halyard, and they afford easy sail handling for a crew of two or a single handed crew with an autohelm.
Where do Reaching Sails and Furlers Fit into the Sail Inventory?
We get this question often at APS from sailors who are confused by what furler works with which type of reaching sail. In this post, we will broadly review the types of sails available for cruising, including sails you may already have on board like a genoa and symmetrical spinnaker. We will classify reaching sails as cruising code zero and asymmetrical spinnakers. Know that each sailmaker will have different ‘in-house’ names for reaching cruising sails and that they can all be designed to be optimal performers for a specific range of wind angles that you and your sailmaker would discuss and agree on. We will then discuss the two types of furling options for reaching sails and their advantages when cruising, especially when sailing with a crew of one or two.
As you can see in the above diagram, different sails perform better within different ranges of wind angles. First, we will discuss the headsail and the spinnakers often found on cruising sailboats, and their wind angle ranges.
Roller Furling Headsails
Headsails on roller furlers offer upwind performance, ease of handling, the safety of furling from the cockpit, and space-saving sail storage on the furler.
Most new cruising boats over 30’ come with a ridged forestay furling system and a 130% genoa as standard equipment. This combination is ideal for sailing close hauled and offers respectable performance on a tight reach. Head off the wind some more and the sail is pretty small and flat for a beam reach (90 degrees apparent wind angle). This is especially true in lighter air (under 10 knots). Any angle deeper than a beam reach in a medium-light air and you may as well furl the sail because the mainsail begins to blanket it while its flat and relatively small size does not perform well. On light air days, the dreaded ‘iron genny’, motor sailing, typically comes in to play when reaching which is not what you went sailing to do.
What about the symmetrical spinnaker you may already have onboard? For true downwind running, the symmetrical spinnaker is a classic way of sailing your boat when your apparent wind angle is in the 110 – 180 degrees range. Although, this includes using a spinnaker pole and sheets and guys, plus the challenges of jibing the sail and pole. Not ideal for a shorthanded crew. Using a spinnaker sock helps to better control the douse, but they are not as easy to use or as space saving as a furled sail.
For dead downwind sailing the symmetrical spinnaker is your best and most stable sail choice, but for reaching angles there are easier and more efficient options to get you there faster. Enter reaching sails.
Reaching Sails & Furlers
For all the reaching points where a furling 130% genoa and the symmetrical spinnaker are not efficient in light air, there is the temptation to turn on the engine when the wind drops. But don’t start the engine. Enter reaching sails. These are the sails and furling options which make sail changes easy for a crew of one or two and keeps your boat quietly moving.
There are two types of sail furlers that are matched to distinctively different types of sails. First, we will discuss the sails.
Cruising Code Zero
For close reaching a cruising Code Zero sail offers outstanding power to drive the boat in medium to light air. These are large genoa-like sails made with a straight luff and a mid-girth that is less than 75% of the foot length. This type of sail will typically be designed within a range for sailing 60 – 130 degrees of apparent wind, and you would target a smaller range with your sailmaker based on your needs and existing sail inventory. These sails excel at close reaching, with performance falling off as the reaching angle increases, but all the while generating substantially more power than the 130% genoa. They also will generally have a higher cut clew that allows for more flexibility in sheeting position and angle. The key factor in terms of furlers choices is that it is an upwind sail with a straight luff.
Image courtesy of Selden
For broader sailing angles of 90 – 150 degrees you will want to switch to an a-symmetrical spinnaker which will be bigger, wider (especially at the top) and much deeper than a Code Zero. The luff is curved and is designed to project more sail area forward. The power and ease of trimming an a-symmetrical may keep your engine quiet in all but a drifter-wind-day. The key factor in terms of furlers is that the sail had a positive curve in the luff.
Image courtesy of Selden
Bottom Up (Code Zero) Furlers
Bottom up (or code zero) furlers are specifically designed for Code Zero sails. The sail has a torsion cable (anti twist) sewn directly into the straight luff of the sail with thimbles at either end. The thimble tack eye connects directly to the furling drum at deck level and the thimble head eye to the top swivel. In order to keep the luff as straight as possible when sailing upwind, the halyard must be extremely tight and highly loaded. To achieve this without overloading the mast, a 2:1 halyard is recommended. This also requires the torsion cable in the luff to be extremely strong and low stretch. The furling drum will be attached to a fixed or retractable bowsprit that is reinforced to handle the halyard tension loads.
To deploy the code zero: The furling drum is attached to the sprit and the continuous furling line is lead aft. The furled sail is hoisted, the furling line is released, begin sheeting in, and the sail immediately rolls out and is sheeted the rest of the way in.
To furl the code zero: The sheet is eased and the continuous furling line is pulled which rotates the furling drum. This rotation is immediately transferred to the torsion cable in the sail. As the bottom of the torsion cables rotates, this travels up the length of the cable and the middle and top, and immediately begin to also rotate and furl the sail – furling the sail from the bottom up.
Image courtesy of Ronstan
The key to these sail furlers working effectively is that the sail has a straight luff, has a mid-girth <75% of the foot length, has a torsion cable is permanently sewn into the luff of the sail, and that torsion cable is highly tensioned by the halyard when in use.
Top Down Furlers
For asymmetrical spinnakers, there is the top down sail furler. Here we are dealing with a top swivel and continuous furling drum, plus a torsion cable. Asymmetrical spinnakers, unlike code zeros, are free flying and the torsion cable is not sewn into the sail but is part of the furler system.
The tack of the sail is attached to a swivel on the furling drum so that as the drum is rotated/furled, the sail does not furl at the tack. The torsion cable runs from the top swivel directly to the drum. The head of the sail is attached to the swivel at the same point that the torsion cable is attached.
To deploy the asymmetrical spinnaker: Follow the same steps as a code zero sail. The furling drum is attached to the sprit and the continuous furling line is lead aft. The furled sail is hoisted, the furling line is released, begin sheeting in, and the sail immediately rolls out and is sheeted the rest of the way in.
To furl the sail: Bring the boat heading to a broad reach. The continuous furling line is pulled as the sheet is let out just shy of allowing the sail to flog, the drum rotates, the torsion cable rotates, and the top of the sail begins to furl around the torsion cable; while the tack does not due to the swivel it is attached to on the top of the drum. As the sail continues to be furled, this action will work its way down the sail to the tack, and eventually, the whole sail is quickly furled around the torsion cable.
Furling and unfurling of the sail are all done from the safety of the cockpit, with a crew of two, or one with an autohelm.
The furling drum is in some cases identical to the code zero version, other than a ball bear swivel has been added to the top of the drum to attach the tack of the spinnaker. The top swivel will usually be the same for both bottom up and top down furlers.
Many of the furler drums can be used for both bottom up and top down furling, as the fitting (swiveling/non-swiveling) on the top of the drum can be quickly changed out. This allows you to use one furler for both code zero sails and asymmetrical spinnakers. If you have questions about this, just give our team at APS a call.
Top down furling units usually include the torsion line or cable and will need to be cut and fitted to length. Finishing the ends is done with mechanical fittings or sleeves allowing boat owners to do it themselves. For those furlers that do not include the torsion cable/line, APS can supply you with either a Harken cable kit or a Ronstan line kit, which both come with cable/line clamps so you can make them up yourself.
Image courtesy of Ronstan
FAQs and Tips for Top Down Furlers
- Old sails can be used on a new furler, but check with your sailmaker to be sure the existing cut of the sail will successfully furl.
- Soft webbing loops on the head of the sail rather than a stainless steel ring will help the head of the sail to start furling more easily.
- If your furler has an adjustable tack swivel (the swivel can slide up and down the torsion line) with a downhaul, be sure it is properly tensioned before furling and unfurling the sail.
- A stiff head patch may interfere with furling at the beginning. As the head patch softens, the sail will begin furling more easily.
- If you have an option to use a larger diameter torsion line/cable, do it. The thicker this is, the better it will translate the rotation of the drum through its entire length, and the better your sail will furl on the slightly larger line circumference.
- Be sure to only use thimbles that are from the manufacture of your furler to ensure a proper fit. Any movement of an improperly sized thimble can lead to deformation of the aluminum thimble over time.
- Ensure your torsion cable/line is the exact length you need for your sail and rig. Follow the manufactures instructions carefully, as they are all different. Doing the initial set up correctly will pay big dividends.
- Because the twist of the furling drum needs to be transferred from the bottom drum to the top swivel, high halyard tension is critical to ensure the torsion line is effective in accomplishing this. Torsion cables, like Harken’s, require less halyard tension.
- When furling, sail the boat down to a broad reach without letting the sail collapse, initially give the sheet a big east which will unload the sail, maintaining a slight tension on the sheet as you furl the sail. Practicing and mastering this smooth maneuver is key to trouble-free furling. Single-handed sailors (with an autohelm) may struggle initially but will master it with just a bit of practice.
- Avoid furling the sail if it is luffing excessively.
- Having the torsion line tight is critical. If the torsion line is not appropriately tight it may not always translate the rotation of the drum to the head of the spinnaker. If you keep rotating the torsion line without the top spinning/furling, the torsion line stores this energy. Now if the furling line is allowed to run backward freely, the line will backspin the torsion line and furling drum. The bottom swivel where the tack is attached can’t keep up and begins to swivel and the foot of the sail now partially furls in the opposite direction around the line. This is called “back twist” and if it occurs, you will have the sail partially furled in two directions – top and bottom. When “back twist” happens, and it will, everyone wants to pull hard on the spin sheet to get the wrap out. All that does is compound the issue and make it harder to untwist. We recommend pulling the furling line in the same direction as the sail was originally furled. Look up and if the top of the sail is wrapped clockwise pull the right side furling line to start re-furling the sail the same way. Once the bottom is flying free from the lower section of the cable you can then either continue to furl the sail or pull the spin sheet to unfurl the sail. If this is not successful, the sail would have to be lowered to the deck unfurled and sorted. Not fun.
- Always watch that the top of the sail is rotating and furling as you pull on the continuous furling line. If it stops, carefully, and slowly ease the furling line back out. If the torsion line is tight enough, the sail is not being sheeted too much, and there is nothing caught at the head of the sail, begin furling again.
When a Top Down Furler is Not Appropriate
If you are dealing with a full-size asymmetrical sail for broad reaching, with mid girths approaching 100% of the foot length, with a deep cut, top down furlers may not be a good option, as the sail may not furl completely. Problems begin with sails having a mid-girth greater than say 90% of the foot length. So be sure to talk with your sailmaker to ensure your sail is designed for top down furling. Otherwise, these larger sails will require a spinnaker sock, which is a good option but is not as easy to use or and space saving as a furler.
Remember to always consult with your sailmaker to ensure your sail, new or existing, is optimized for furling, and the apparent wind angles you will be sailing most often. Call our team at APS if you have questions on the different features in bottom up or top down furler. Proper planning will lead to trouble-free, and more enjoyable sailing.
Cleats are fittings to which a line is secured, either temporarily or permanently. We are going to explain the seven main cleat types found on sailboats, and some of their uses: Horn Cleats Self-Jamming Horn Cleats Cam Cleats Double Cam Cam Cleats Clam Cleats V Cleats Lance Cleats SHOP ALL CLEATS Horn Cleats Primary Uses: Anchoring, mooring and docking a boat. Also classically use on the mast to secure halyards. Sizes: Line diameters: 3/32” – 2”+ Horn cleats are most […]
Cleats are fittings to which a line is secured, either temporarily or permanently. We are going to explain the seven main cleat types found on sailboats, and some of their uses:
- Horn Cleats
- Self-Jamming Horn Cleats
- Cam Cleats
- Double Cam Cam Cleats
- Clam Cleats
- V Cleats
- Lance Cleats
Primary Uses: Anchoring, mooring and docking a boat. Also classically use on the mast to secure halyards.
Sizes: Line diameters: 3/32” – 2”+
Horn cleats are most commonly your deck cleats. They are the strongest type of cleat, and the only type you should use for anchoring, mooring and docking a boat.
Typically they are through bolted to the boat’s deck with two bolts running through the cleat, then through the deck and secured with lock nuts below. Given the huge loads these can be expected to take, reinforcing the deck where they are mounted and using backing plates where applicable is expected.
For cleats used for the heavy loads of mooring or anchoring’s, cleats that use four fasteners plate will better spread the load to the deck.
The majority of horn cleats will be open bases which allows you to pass a loop of line through the throat of the cleat. Some specialty, low profile or utility cleats may have closed bases.
Horn cleats are made from many different materials. For lighter loads, wood and nylon can be used for utility, but for heavy loads on the boat such as anchoring, mooring, and docking, aluminum or stainless steel is needed.
Galvanized steel is another material option, and used almost exclusively on docks and wharves.
In general terms, to choose the cleat length, it should be 1” (tip to tip) for every 1/16” of line diameter; and dock lines should be 1/8” in diameter for every 9 feet of boat length. For example, if a boat is 45’ in length, it would require 5/8” dock lines. Using 5/8” dock lines means the boat should have 10” cleats. These sizing guidelines are the minimum, and upsizing line diameter and cleat sizes add an additional margin of safety. Also, chocks and cleats need to be large enough to accommodate chafe gear and the doubling of lines for extreme weather events. Also, if a cleat is dramatically too big for the line diameter, the line will not hold as well on the cleat and could slip, so don’t supersize your cleats.
Self-Jamming Horn Cleats
Primary Uses: Loaded lines requiring quick cleating when adjusting.
Sizes: Line diameters: 1/4” – 1/2”
Self-jamming horn cleats work well with genoa sheets, topping lifts and reefing lines – loaded lines requiring quick cleating when adjusting. One side of the base has a “V” or jamming shape to it that “locks” the line more quickly. The cleat is mounted such that the line under load is lead the side without the “V” jam, then to the side with the “V” jam. This single wrap around the base of the cleat locks the load of the line more quickly and makes completing the cleat hitch easier with the now much less loaded tail. The cleat needs to be mounted such that the side without the “V” jam faces away from the loaded line (farthest away from the source of the load). These will be made of aluminum or stainless steel.
Primary Uses: Frequently adjusted control lines and sheets with loads that can be handheld. Also used on some higher loaded lines, as larger cam cleats can accommodate loads approaching 1000 lbs breaking strength.
Sizes: line diameters 3/32” – 5/8”
Cam cleats make cleating and uncleating an easy single fluid motion. The spring-loaded cams will automatically open and allow the line slide in between them as you pull a loaded line between them. To uncleat, tension the line by hand while pulling it up and away from the cleat, and it will simply slide out of the cams.
Cam cleats generally come in three sizes – not surprisingly, small, medium and large. Each size has a small range of diameters it will works with, which will differ slightly from each manufacturer. They will offer cleating for line diameters from 1/12” all the way up to 5/8”.
Cam cleats are made from three types materials: composite, aluminum and stainless. Composites (think reinforced high tech plastics) offer good long lasting performance. Aluminum generally offers greater resistance to UV degradation over time and can be rebuilt (new ball bearings and plastic components), but they will be a little bit more expensive. Stainless steel cam cleats are long-lasting and capable of holding high loads, but are much more expensive, and are more often found on superyachts.
The different accessories that can be added to cam cleats allow you to optimize them for a dedicated task.
Rear fairleads can be metal or composite construction, and allow you to pull and cleat a line different angles.
Saddles can be metal or composite construction, and keep the line associated with the cleat when it is uncleated, and makes for fast recleating.
Rope Guides will consist of a stainless steel wire held in place by an under cleat composite plate and redirect a line that is not fairly lead into the center of the cams. It is meant for use with only light to moderately loaded lines.
Wedges allow you to adjust the angle of the cleat on a flat surface either backward or forward to better align the cam cleat with the loaded line, and create a fairlead.
Riser and Curved Surface Adapters either allow you to either mount a cam cleat to a curved surface or raise the cleat off of a flat surface to create better access or clearance.
*Illustrations courtesy of Ronstan
Double Cam Cam Cleat
Primary Uses: Two-speed mainsheet systems or where two lines need to be cleated in an area of minimal space.
Sizes: One size, for line diameters of 5/16” – 3/18”
This is a unique solution when you want the convenience and performance of a cam cleat, but don’t have enough room to mount two separate cam cleats. This is a space saver. The center post has line gripping ridges, but is stationary, while one outside spring-loaded cams engage separately lead lines.
Primary Uses: Small control lines, hanging fenders, securing a lee cloth, utility applications.
Sizes: Generally four sizes of cleats, covering a line diameter range of 3/32” – 5/8”
A clam cleat holds line fast (cleated) between two stationary checks which have ridges. The ridges face downward and towards the source of the load on the line. The two checks and the ridges on them progressively get closer together the farther down you go from the top. To cleat, the loaded line is pulled back and down into the cheeks, then released. The load on the line will pull it into the cleat, thus cleating the line. The more load on the line, the deeper the line is pulled into the cleat, and the more securely it is cleated. Simple design, easy to use, but not as easy to uncleat a loaded line as with a cam cleat.
Below are some of the most popular cam cleats, with other, more specialized styles available.
Open clam cleats are easy to use and don’t keep the line captive when it is uncleated.
Side entry clam cleats are available either open on the right or left and in smaller sizes. These cleats allow lines that are not fairly lead to be redirected into the cleat by the integral fairlead, and the ease of line remove out the side when it is uncleated.
Captive clam cleats are available either open on the right or left and in smaller sizes. These cleats allow lines that are not fairly lead to be redirected into the cleat by the integral fairlead and keeps the line captive when it is uncleated, and ready to cleat again.
The closed becket clam cleat has a ‘tunnel’ under the body of the cleat that allows you to run the line under the cleat and dead-end with a knot when creating a 2:1 purchase.
Top roller fairlead clam cleats allow lines to enter from above, and redirects them into the cleat with a plain bearing sheave.
Bottom roller clam cleats allow lines to enter from below, and redirect them into the cleat with a plain bearing sheave.
Inline clam cleats are clam cleats mounted to a composite line brake. They allow for adjustment without the use of tools and provide a 2:1 purchase anywhere along a line.
*Illustrations courtesy of Clamcleat
Primary Uses: Cleating small control or utility lines
Size: Generally available in one or two sizes, covering line diameters 1/8” – 1/4”
These are an old and simple design where the line is run permanently through the cleat. They work well with soft small diameter line that can be pulled deep into the ‘V’ portion of the cleat line for good holding. A firm line can be problematic, as it does not always get deep enough into the ‘V’ to create enough friction and can sometimes fall free.
Primary Uses: ‘Parking’ (cleating) a line temporarily.
Size: Available in two sizes, covering line diameters of 1/8” – 7/16”
This cleat has a single spring-loaded cam on one side, and a roller on the other. They are available with the cam on either the right or left side. The line is lead through the line permanently and can be pulled over into the cam and held until it can be secured with a cleat in another location on the boat. Some small raced boats may mount on the mast with the spinnaker halyard run through it. When the spinnaker is hoisted the bow person can pull the halyard over and into the cam until the line is cleated in the cockpit (tensioning the line from the cockpit will pull it free of the Lance cleat cam).
Tying a line to a cleat should be easy and secure, but walk down any dock and you will be amazed at the creative ways lines are ‘secured’ to cleats. We will show you the correct and the incorrect ways to secure a line to a horn cleat using a cleat hitch. You might be surprised what you learn, even if you’re ‘salty.’ Half Wrap Cleat Hitch This is most commonly seen as the standard cleat hitch in North America, […]
Tying a line to a cleat should be easy and secure, but walk down any dock and you will be amazed at the creative ways lines are ‘secured’ to cleats. We will show you the correct and the incorrect ways to secure a line to a horn cleat using a cleat hitch. You might be surprised what you learn, even if you’re ‘salty.’
Half Wrap Cleat Hitch
This is most commonly seen as the standard cleat hitch in North America, but it is mistaken as being the best all-around cleat hitch which can get you and your boat into trouble. This is a ‘lunch time’ or ‘fuel dock’ way to cleat a line. It is not recommended when you will be out of sight of your boat, and not for overnight use.
The line is taken around the two ends of the base of the cleat, but not a third time which would create a complete encirclement of the base (then crossed over the top and hitched on the second cross over). It is an open wrap and can allow even a properly sized line to slip through this cleat hitch until the bitter end pulls out and the line comes off the cleat. Smaller diameter line (relative to the size of the cleat) or slippery line are more prone to slipping off the cleat and should not use a half warp cleat hitch. Adding more figure-8s is advocated for more holding by some, but this is not the correct solution. Use the use a full wrap or multi wrap cleat hitch to add more line holding ability.
It is an open wrap and can allow even a properly sized line to slip through this cleat hitch until the bitter end pulls out and the line comes off the cleat. Smaller diameter line (relative to the size of the cleat) or slippery line are more prone to slipping off the cleat and should not use a half warp cleat hitch. Adding more figure-8s is advocated for more holding by some, but this is not the correct solution. Use the use a full wrap or multi wrap cleat hitch to add more line holding ability.
If you have undersized cleats, you may be forced to use a half warp cleat hitch temporarily, as the cleat may not be big enough to accommodate a full warp cleat hitch.
Full Wrap Cleat Hitch
This is more commonly seen as the standard cleat hitch in Europe. It is the recommended cleat hitch for all docking, for both temporary and extended periods. It takes a full wrap around the base of the cleat creating a closed loop before taking your first cross over the top of the cleat. The line will be stacked on the one end of the cleat (not the other) with two wraps. These lines under tension create more friction, thus better ‘locking’ the line to the cleat base.
Multi Wrap Cleat Hitch
When a cleat is many times too big for the line diameter being used, you will want to consider using the multi warp cleat hitch. Think of the base of the cleat as a winch drum. The more wraps, the more friction, and thus the more holding power of the cleat hitch. Once you have enough wraps on the cleat base, you will follow with a cross over, and another cross over with a hitch.
Cleat Size and Line Diameter
Selecting line diameters and cleat sizes are dependent on your boats length, displacement, and windage. If your boat is average displacement and windage for its length, using the boat length alone is sufficient. Horn cleats are sized to optimize specific line diameters. Cleat length from tip to tip should be 1″ for every 1/16″ of line diameter, and dock lines should generally be 1/8″ of diameter for every 9 feet of boat length.
For example, if your boat is 36′ in length, it requires 1/2″ dock lines. Using 1/2″ dock lines means that your cleats need to be 8″ long to accommodate and single dock line. In this example, a 6” cleat would be said to be undersized, and a 10” cleat oversized. Note that these are general minimums. As with all docking and mooring equipment, bigger is better. Having cleats that are oversized allow multiple lines to be tied off on one cleat. No one complains about having an oversized anchor or oversized fenders in stormy weather.
Dock and Rode Line Type
Stretch and strength is required in your dock and rode line to reduce shock loading your deck hardware and to give your boat a better, jolt free movement. It is common for these lines to be an afterthought which can lead to damage and discomfort aboard. It is also tempting, to save money, to use retired halyards, sheets or guys for dock lines, but DON’T. They are strong enough for the task but are by design low stretch. Use either three strands, double braided mooring line, or 8-plate mooring line. These are by design for docking or anchoring, strong, and relatively stretchy.
There are varying opinions on what is the correct cleat hitch to use. “Chapman’s Piloting and Seamanship”, Brion Toss’ “The Complete Rigger’s Apprentice” and the United States Power Squadrons teach the Half Cleat Hitch, while the Royal Yacht Association, Hin’s “Knotting and Splicing”, Peter and J.J. Isler’s “Sailing for Dummies”, and Andrew Sloan Draper & Charles Welsh’s “Drapper’s Self Cuture” teach the Full Half Cleat. Ultimately your experience will lead you to chose the cleat hitch that is correct for your line type, diameter and slip; the cleat length; and the duration of your tie-up.
What are Stand Up Springs & Boots? Common sailboat block accessories, stand up springs and boots are meant to keep a block upright. Metal springs come tapered or straight in various sizes to fit a range of blocks. Stand up boots made of PVC are offered in large and small sizes and black or gray. After installation when the line running through the block is slack, the block will not collapse on its attachment point (deck of the boat, traveler car, etc…). Why […]
What are Stand Up Springs & Boots?
Common sailboat block accessories, stand up springs and boots are meant to keep a block upright. Metal springs come tapered or straight in various sizes to fit a range of blocks. Stand up boots made of PVC are offered in large and small sizes and black or gray. After installation when the line running through the block is slack, the block will not collapse on its attachment point (deck of the boat, traveler car, etc…).
Why Use Stand Up Springs & Boots
- Springs and boots keep blocks in the correct orientation. With the block standing up and oriented in the direction is was when it was last loaded, lines run freer when they reload after a tack or and jibe. A mainsheet block mounted to a traveler car will be less likely to tangle in the mainsheet when it is supported and not falling into the line during tacks and jibes.
- They keep blocks from hitting the deck. An example would be a spinnaker guy lead block that is mounted to the deck. Each time the bock is unloaded it falls and marks and eventually damages the deck.
- Stand up boots, which have a solid construction,offer an added value in that they shed lines, thus preventing snags and tangles.
Where to Use Stand Up Springs & Boots
Try stand up springs & bloots for:
- Lead block on the deck
- Mainsheet blocks on traveler cars
- Mainsheet ratchets mounted on the cockpit sole
- Upright aft turning blocks for spinnaker sheets.
How to Install:
If your spring is too large to be easily compressed by hand, we recommend using zip ties for installation.
- Using 3 zip ties, compress the spring about 3/4 of the way down while cinching ties. Work the ties away from each other until they are equally spaced while cinching tighter.
- Once the spring is flattened with the zip ties, put it on top of your fixed point and shackle.
- Install block onto the shackle.
- Snip off ties making sure your fingers are clear of the spring and all rings and attachments are inside.
Large and small boots can be equally challenging. The zip tie trick is recommended for both sizes.
- Using 3 zip ties equally spaced, compress the boot flat and tighten ties down.
- Slip loosely cinched zip tie through your shackle. Put boot ontop and use the tie to pull the shackle through the boot. Snip zip tie off of shackle.
- Install block onto fixed point shackle with your clevis pin.
- Snip off ties making sure to tuck ring or shackle attachment inside of the boot.
Trigger release shackles come in various sizes and configurations that are ideal for jib or spinnaker halyards, spinnaker sheets and guys, and tack lines; or jobs where you would want to release the shackle under load. More efficient than the snap shackle, the trigger shackle has a streamlined design with no external parts to catch, so they run smoothly. The release mechanism, the trigger, is located inside the housing of the shackle making it very unlikely that it will catch […]
Trigger release shackles come in various sizes and configurations that are ideal for jib or spinnaker halyards, spinnaker sheets and guys, and tack lines; or jobs where you would want to release the shackle under load. More efficient than the snap shackle, the trigger shackle has a streamlined design with no external parts to catch, so they run smoothly. The release mechanism, the trigger, is located inside the housing of the shackle making it very unlikely that it will catch and accidentally open. Another advantage to the trigger shackle is that it is generally stronger and more compact than a snap shackle.
HOW DOES IT WORK
A trigger shackle is made up of a hinged bail, the shackle body with the trigger house within, and a swiveling bail. Lines are attached, or spliced, to the swiveling bail. With the shackle open, insert the sail attachment point (ring or eye) into the shackle housing and close the shackle until you feel it snap into its locked position. Inside the shackle housing is a small spring loaded trigger that, when pressed, opens the bail and releases the sail.
WHAT IS A FID
One advantage to the trigger shackle is being able to release under load. To release under load, use a fid. When releasing it under load, there are 2 reasons to use a fid: 1) It is difficult to actuate the trigger with just your finger while the shackle is highly loaded 2) You should keep your fingers away from the recoil of the shackle to prevent injury. A fid is conical pin or spike. Insert the fid into the space where the trigger is to depress the trigger and open the shackle.
TYPES OF TRIGGER SHACKLES
The standard bail is the most popular. With a standard size bail in relation to the shackle, you should choose your size based on the appropriate working load (not breaking load). Standard bail trigger shackles are ideal for a jib halyard, a spinnaker halyard, spinnaker sheet, or a spinnaker tack line.
Large bail trigger shackles are designed for spinnaker sheets and guys. When spliced to the guy, you can snap the spinnaker sheet shackle to the larger bail used for the sheet. Another option is to splice both your sheet and guy to one large bail shackle, allowing you to save weight and simplify spinnaker attachment, but you do lose the flexibility of detaching the sheet and guy separately which is helpful if the wind lightens up or you are preparing for a ‘peel’ to another spinnaker.
A clevis bail trigger shackle is perfect for a permanent application where you want it to stay with the boat. These are very popular to attach a jib to the bottom of a furler drum.
Snap shackles come in a variety of sizes and configurations, and are generally used for halyards, sheets, guys, and tack lines, along with a few specialty applications. The beauty of a snap shackle is the easy open and release function. Let’s take a closer look. HOW DOES IT WORK A few basic components are found on every snap shackle. The hinged bail, the shackle body bail to which your line is attached, a spring loaded plunger pin with a pull […]
Snap shackles come in a variety of sizes and configurations, and are generally used for halyards, sheets, guys, and tack lines, along with a few specialty applications. The beauty of a snap shackle is the easy open and release function. Let’s take a closer look.
HOW DOES IT WORK
A few basic components are found on every snap shackle. The hinged bail, the shackle body bail to which your line is attached, a spring loaded plunger pin with a pull ring on the end. When you pull the ring,the spring loaded plunger pin slides back until it disengages. At this point you can swivel the hinge open and then release the pin. Once the shackle is open, you can now attach what you need- clew of a jib, head of spinnaker, etc. Simply press the free hinge back closed, and it locks tight with a ‘snap’.
Now, if you are concerned about the snap shackle leash or ring catching on some part of the boat while in use and accidentally opening up, you can secure it with a few wraps of rigging tape around shackle covering the pull ring.
It’s important to remember that snap shackles cannot be safely released under load. If you’re in a situation where you might need to release a shackle under load, like when ‘peeling’ to a different spinnaker, you’re going to need a Trigger Shackle.
HOW TO CHOOSE
The first thing to help decide which one you need is to figure out the load of the application and compare that to the safe working load (not the breaking load) of the shackle. Also, take into consideration what you’re attaching it to. Is the body of the shackle large enough to accommodate what will be inserted into it?
The first type is a fixed bail snap shackle. The bail is part of the shackle body and does not swivel. This works for applications where you don’t want any twisting, or the application is simple and a more expensive swivel block is not warranted.
Next, the most common, is the standard bail snap shackle. The bail is connected to the shackle with a swivel. A 360 degree range allows twists in an attached line to work themselves out, or a twisted spinnaker to untwist more easily on the hoist. Popular for jib and spinnaker halyards, and sheets.
Next, is the large bail. The larger bail allows more space to splice or luggage tag lines. Some prefer to connect both the guy and sheet to one shackle. Or, with the guy spliced permanently to the large bail, there is room to attach the snap shackle of the sheet to it when using separate spinnaker sheets and guys.
Finally, the clevis bail, or a screw bail. The Wichard bail comes with a clevis pin, while the Ronstan bail uses a flat head screw. These are ideal for permanent attachments, and especially popular to attach the tack of a jib to the base of the furler drum.
Some snap shackles come or can be fitted with accessories to help make opening easier whether it’s a braided line or a leather leash. These are attached permanently to the pull ring on the end of the plunger, and add extra area to grip for ease of opening.