How to Sever the Liferaft Painter?

[RUSTYNAIL]

You need to read the instructions for your Zodiac life raft. I would bet your life raft has a blunt end knife in a pocket right near the entrance to the canopy on the inside of the life raft tube. Most offshore life rafts also have a floor that needs to be inflated manually with the hand pump in the equipment bag that many mariners aren't aware of. The inflated floor will help insulate you from the cold water, and add buoyancy and comfort. The raft has a bag with lots of repair items, and equipment depending on what level of raft you bought. A raft with a bracket will have an automatic hydrostatic release designed to release the strap that holds the raft in the bracket down to about 3 meters, and a plastic breakaway link that the painter is connected to with a shackle so the vessel wont pull the raft down once the entire painter is pulled out if the boat sinks below the length of the painter. Older releases used a smaller line that would break before pulling the raft under. There are on line videos from" Hammar" releases that show how the release works, and breaks the painter connection when needed.. The life raft box's painter must be connected to something to pull the long painter out, if not the whole box will float away without inflating until someone gets to it and manually pulls a very long painter line out. The last few feet of painter is connected to the CO2 cylinder pin.

[boatman61]

Originally Posted by jackdale

I always carry a knife.

A man is not a seaman without a knife...........

[Bash]

Originally Posted by boatman61

A man is not a seaman without a knife...........

Yes. And a lifejacket without a knife is just a PFD.

[Bluewaters2812]

Originally Posted by Sabbatical II

I just got thinking, I've got a nice new Zodiac liferaft on deck tied to the boat with a bowline. I've been told to just throw it over to launch and I can do that. But once in it do I have to have remembered to bring my knife so that I can cut the painter and not get dragged down with the ship? Can anyone tell me what type of painter release system they have? Surely I don't have to go back & get the knife?

Tie a bowline at the raft end?

[Weyalan]

Use a weak link... your painter line shouldn't require more than 15kg to initiate inflation. Your inflated liferaft will have, on assumes, several hundred kg of positive buoyancy. So, for the sake of argument, a 50kg cable tie will be strong enough to allow your painter to initiate inflation (in the event that you don't do so yourself, by manually pulling the painter), but will be weak enough to break before your sinking boat could pull the liferaft under.

Alternatively you could use a hydrostatic release unit. Google C. M. Hammar HRU for more details. This unit has a spring loaded blade that will cut through 8mm diameter (5/16") restrining rope, when it is subjected to a certain hydrostatic pressure (typically around 4.5m).

[xymotic]

Spinlock Safety Tether S Cutter (w/velcro pouch and lanyard)

[Andrew Troup]

In one of the early paying-crewed Round the World the Wrong Way races (I forget what they were officially called back then) the crew on one of the boats wished their bowman wasn't carrying a knife when he went suddenly berserk and started stabbing himself.

The moral of the story is, don't wear an auto inflating PFD under your wet weather jacket.

[Watermann]

There are lots of misconceptions regarding liferafts and their rigging going on here...

The objective is to setup the raft to where it takes no human intervention to release from the cradle, float to the surface, inflate and detach itself from a sinking boat. Properly setup, this is what should happen. Of course, if you have the time and means, deploying it manually in an emergency should not be a hassle either and is the preferred method.

You need:
-A hydrostatic release unit (HRU) with appropriate lashing strap/line
-A weak link that attaches the liferaft painter to a fixed object on the vessel (generally the cradle has an attachment point for a shackle or some HRU's incorporate a weak link attachment for the painter)

The hydrostatic release merely releases the raft canister from the cradle so that the canister can float to the surface. It plays no part in actually inflating the raft. HRU's will not release due to large waves, getting swamped, etc. It is VERY important to rig the hydrostatic release exactly as the manufacturer prescribes. Once the canister leaves the cradle, the painter is pulled out. Painter lengths vary and will be stamped on the canister. The bitter end of the painter MUST be rigged to a fixed point on the boat (via a weak link) or the raft will not inflate automatically. You do not want the painter to release from the vessel when the hydrostatic release pops. If the painter is not pulled out to its full length prior to detachment from the vessel, the vessel will sink and the raft will not have inflated, presenting a smaller target for rescue vessels, and a bigger problem for you as you float around in the water trying to find it (especially not fun in bad wx and/or in the dark). As the vessel sinks and the painter reaches its maximum length, it pulls the pin on the CO2 bottle valve which inflates the raft. The weak link should break and the inflated raft is now free from the vessel.

Remember, I'm describing completely automatic deployment of the raft. If deploying the raft manually, it is recommended to cut the painter after you have inflated the raft (and everybody's aboard) and avoid having to rely on the weak link and/or risking the painter fouling on another part of the boat. But setting up for completely hands-off, automatic deployment is crucial. This is how rafts are setup on inspected vessels and anything short of this rig setup will result in a failure of the COI and cause a No-Sail condition. The last thing you need after a sinking is to watch your liferaft canister sink down beneath you, carefully and securely lashed to the boat.

[FearfulGirl]

We had a pocketknife by the companionway and a knife tied to the life raft. Both of them rusted shut with a month or so.

[Bluewaters2812]

Originally Posted by Watermann

There are lots of misconceptions regarding liferafts and their rigging going on here...

The objective is to setup the raft to where it takes no human intervention to release from the cradle, float to the surface, inflate and detach itself from a sinking boat. Properly setup, this is what should happen. Of course, if you have the time and means, deploying it manually in an emergency should not be a hassle either and is the preferred method.

You need:
-A hydrostatic release unit (HRU) with appropriate lashing strap/line
-A weak link that attaches the liferaft painter to a fixed object on the vessel (generally the cradle has an attachment point for a shackle or some HRU's incorporate a weak link attachment for the painter)

The hydrostatic release merely releases the raft canister from the cradle so that the canister can float to the surface. It plays no part in actually inflating the raft. HRU's will not release due to large waves, getting swamped, etc. It is VERY important to rig the hydrostatic release exactly as the manufacturer prescribes. Once the canister leaves the cradle, the painter is pulled out. Painter lengths vary and will be stamped on the canister. The bitter end of the painter MUST be rigged to a fixed point on the boat (via a weak link) or the raft will not inflate automatically. You do not want the painter to release from the vessel when the hydrostatic release pops. If the painter is not pulled out to its full length prior to detachment from the vessel, the vessel will sink and the raft will not have inflated, presenting a smaller target for rescue vessels, and a bigger problem for you as you float around in the water trying to find it (especially not fun in bad wx and/or in the dark). As the vessel sinks and the painter reaches its maximum length, it pulls the pin on the CO2 bottle valve which inflates the raft. The weak link should break and the inflated raft is now free from the vessel.

Remember, I'm describing completely automatic deployment of the raft. If deploying the raft manually, it is recommended to cut the painter after you have inflated the raft (and everybody's aboard) and avoid having to rely on the weak link and/or risking the painter fouling on another part of the boat. But setting up for completely hands-off, automatic deployment is crucial. This is how rafts are setup on inspected vessels and anything short of this rig setup will result in a failure of the COI and cause a No-Sail condition. The last thing you need after a sinking is to watch your liferaft canister sink down beneath you, carefully and securely lashed to the boat.

Everything you have said sounds like good, common sense advice, so thanks for that. Have you any idea of the rough budgetary cost of this sort of life-raft/equipment?

[hellosailor]

"We had a pocketknife by the companionway and a knife tied to the life raft. Both of them rusted shut with a month or so."

Nothing personal, but it is the bad carpenter who blames the tools. My parents generation ruined the world of cutlery by buying into the myth that stainelss steel would cure everything. Which is why chefs are back to using carbon-steel blades now.

I had done a lot of legwork to buy the best possibel dive knife, best in terms of alloy that would hold a fine edge, not rust, be strong. IIRC that was 440C steel at the time. Funny thing, being used in slat water all the time, it would start to rust in the corners by the bolster, no matter how well it was washed and dried after use.

The answer is, a spot of wax or oil, and the rust can't get started.There are waxy products designed just to keep edges on blades, plain bees wax or white wax will work very nicely. When you need to use the knife, that wax is not going to slow it down at all.

And, you don't use a folding knife, since the hinge will trap crud and moisture and may fail to open or to lock open. A spare 4-6" kitchen knife isn't expensive and when sheathed, will do.

Then there's also the new way to avoid rust, buy a ceramic knife. A Boker folding or straight knife, or one of the many kitchen kives usually with white ceramic blades, often $15 for a set of 3 in the discount stores, and you'll have a damn fine blade with no rust possible. Yes, they are brittle compared to steel, but that shouldn't be a problem here.

[estarzinger]

Originally Posted by Watermann

-A weak link that attaches the liferaft painter to the vessel

Just FYI . . . The current official (ISO & ISAF) position is to require a knife and NOT a weak link. Weak links can be dangerous, potentially accidentally allowing the raft to break free and drift away when not intended.

The current ISO and ISAF spec for a life raft painter line is:

5.2.1.2 Properties of the painter line:
The painter line shall be positioned at the entrance to the liferaft.
The length of the painter line shall be at least 9 m.
A coloured indication shall be visible at less than 1 m from the firing point.
The painter line shall be efficient and shall be easy to handle and to pull.
The breaking load of the painter line, and of its attachment system to the liferaft, shall not be less than 7,5 kN. Note: that's 1686lbs breaking strength.
The painter-line attachment system shall be constructed so as to not damage the liferaft on failure of the attachment system.
The painter line shall withstand weathering.

Also:

5.2.8.2.4 Safety knife
A safety knife shall be securely stowed in a visible manner in the vicinity of the painter-line attachment. The knife shall be secured to the liferaft by a line of sufficient length, to enable the painter line to be cut. The knife shall be stowed, so as not to damage the liferaft on inflation, or when the latter is launched. It shall be so designed that it does not damage the liferaft if accidentally dropped. It shall be sufficiently buoyant in order to float in water

[Sabbatical II]

Originally Posted by estarzinger

Just FYI . . . The current official (ISO & ISAF) position is to require a knife and NOT a weak link. Weak links can be dangerous, potentially accidentally allowing the raft to break free and drift away when not intended.

5.2.8.2.4 Safety knife
A safety knife shall be securely stowed in a visible manner in the vicinity of the painter-line attachment. The knife shall be secured to the liferaft by a line of sufficient length, to enable the painter line to be cut. The knife shall be stowed, so as not to damage the liferaft on inflation, or when the latter is launched. It shall be so designed that it does not damage the liferaft if accidentally dropped. It shall be sufficiently buoyant in order to float in water

Thanks Evans. I did contact the manufacturer and they have confirmed that a knife is indeed located just inside the doorway. (next to the light switch?)

[Leukothea]

Originally Posted by Bluwaters2812

Everything you have said sounds like good, common sense advice, so thanks for that. Have you any idea of the rough budgetary cost of this sort of life-raft/equipment?

HRU's are maybe 100-200 USD. The Hammar H20 is a very popular model and includes a weak link that you attach the raft painter to. The HRU is not specific to any raft - just incorporate it into whatever strap you have securing the raft canister to its cradle. Most have a flat rubber strap with shackles on each end. You rig the HRU between one of the strap ends and the cradle.

The Hammar H20 has a two year service life and must be replaced, if you're legally required to (recreational vessels probably aren't in most countries).

Originally Posted by estarzinger

Just FYI . . . The current official (ISO & ISAF) position is to require a knife and NOT a weak link. Weak links can be dangerous, potentially accidentally allowing the raft to break free and drift away when not intended.

The current ISO and ISAF spec for a life raft painter line is:

5.2.1.2 Properties of the painter line:
The painter line shall be positioned at the entrance to the liferaft.
The length of the painter line shall be at least 9 m.
A coloured indication shall be visible at less than 1 m from the firing point.
The painter line shall be efficient and shall be easy to handle and to pull.
The breaking load of the painter line, and of its attachment system to the liferaft, shall not be less than 7,5 kN. Note: that's 1686lbs breaking strength.
The painter-line attachment system shall be constructed so as to not damage the liferaft on failure of the attachment system.
The painter line shall withstand weathering.

Also:

5.2.8.2.4 Safety knife
A safety knife shall be securely stowed in a visible manner in the vicinity of the painter-line attachment. The knife shall be secured to the liferaft by a line of sufficient length, to enable the painter line to be cut. The knife shall be stowed, so as not to damage the liferaft on inflation, or when the latter is launched. It shall be so designed that it does not damage the liferaft if accidentally dropped. It shall be sufficiently buoyant in order to float in water

The only problem with that, is that it potentially allows for the raft to be pulled under with the sinking boat (depending on the buoyancy of the raft and how far one's painter is rated over the minimum breaking strength). When deploying the raft manually, you should secure the painter to the boat to prevent an accidental breakaway anyways. You would then use a knife to cut the painter once safe in the raft. The weak link is merely there to sever the link between the boat and raft in the event that a knife is not available or no one makes it to the raft before the boat sinks. I'm not advocating an either/or (knife/weak link), nor should you wait for automatic deployment if you can reach and launch the raft manually.

I don't understand the reluctance to have a raft deployment system that is 100% hands-off for operation in the event you don't have time or the ability to reach it if the boat sinks.

[estarzinger]

Originally Posted by Leukothea

I don't understand the reluctance to have a raft deployment system that is 100% hands-off for operation in the event you don't have time or the ability to reach it if the boat sinks.

The official position is that empirical experience says is that there is a much greater risk of the raft accidentally breaking away with a weak link than of a raft being dragged under without a weak link.

I personally have no perspective on this. However, I do know that people who have vast specific knowledge and data and expertise write these ISO and ISAF recommendations.