The first week on the French canals taught us that a sea-going boat is badly equipped for locking. We arrived with a cockpit full of ocean kit and not one item that made a Burgundy lock easier. Forty-odd locks later we had a kit that worked, and it was mostly cheap, mostly improvised, and almost none of it came from a chandler's heavy-weather aisle. Here is what we ended up with, and what we threw back in the lazarette.
Start with the lock dimensions
You cannot kit out for a lock you do not understand, so the numbers first. The standard French canal lock is built to the Freycinet gauge: a chamber around 39 metres long, 5.2 metres wide, with a minimum depth of about 2.2 metres. The boats it was sized for run up to 38.5 metres long and 5.05 metres in the beam, which is why a 12-metre cruiser feels lost in one and a 15-metre barge fills it.
What matters for your kit is the rise. Many locks lift you several metres, and some fill right to the brim, which means your fenders and warps have to cope with the water rising fast and the boat trying to climb the slimy chamber wall. Get that picture and the gear list writes itself. If you are new to the mechanics, the how a french lock works walkthrough explains the sequence before you commit your boat to a chamber.
Warps: length, hand and how many
The single biggest upgrade was longer warps. In a deep lock you drop a loop over a bollard high on the chamber wall and tend the line as the boat rises or falls, and a short ocean dock line leaves you stretching and swearing. We carry four working warps of around 15 metres each, soft three-strand that runs easily round a bollard and is kind on the hands, plus two longer 25-metre lines for the deepest locks and for breasting alongside a town quay.
A loop spliced or tied in one end makes lassoing a bollard far quicker, and a fender knot or simple stopper at the working end stops it whipping out of your grip. Soft polyester or a soft-lay nylon beats hard, slick modern line here: you are handling these by hand, fast, often wet, and grip matters more than ultimate strength. The loads in a canal lock are nothing like a sea mooring, so do not over-specify the diameter; a fat warp is just harder to throw and coil.
The boat hook earns its keep
On the canals the boat hook is in your hand more than the wheel. We carry two: a long telescopic one that reaches up to a high lock bollard or a quay ring you would otherwise miss, and a short stiff one for fending off and for hooking ladder rungs. The telescopic length is the thing to get right, because the reach from a low boat deck up to a bollard set back from a brimming lock wall is further than you expect.
Buy a hook with a proper head that both pushes and pulls, and check the join on a telescopic one is solid, because a hook that collapses just as you reach for the bollard puts you sideways across the chamber. A cheap hook fails at the worst moment. This is one place to spend.
Fenders that paddle
Ocean fenders sit too high for a brimming lock. The advice from old hands is that fenders must paddle, meaning they need to ride low enough to protect the hull right down at the waterline and a little below, because the lock wall is roughest there and the boat climbs as the chamber fills.
We rig fenders lower than we ever would at sea, and we added a couple of cheap car-tyre style fenders and a fender board, a stout plank hung outside two fenders, for the locks with vertical ladder recesses and protruding stonework. The fender board spreads the load and stops a single fender popping up and out as the boat rises. It looks agricultural. It works.
A second tip: hang fenders on both sides going into a narrow chamber, because you will touch the wall you were not expecting to. The canal lock kit you carry for locking doubles as your overnight mooring kit on a town quay, so size the fenders for both jobs.
The small kit that saves your hands and temper
Gloves. Proper grippy work gloves, a pair each, kept where you grab them before a lock and not buried below. Lock walls grow slime and the warps run through your hands under load; bare hands get cut and rope-burned in a single bad day.
A pair of long-reach hooks or a small grapnel for retrieving a dropped line. A windlass key is not needed on most VNF-operated locks, but a sturdy short boat hook for poking the activation rod or the dangling pole at automatic locks certainly is. Sun hats and water, because a flight of locks in a Midi summer is hot, sweaty work and dehydration makes you clumsy exactly when you need to be precise.
We also keep a roll of cheap rags and an old fender sock, because everything that touches a lock wall comes back green and slimy, and a clean cockpit lasts about one chamber.
What we stopped carrying
The ocean stuff stayed below. Heavy mooring chains, the storm warps, the big offshore fenders that float too high, the snubber, the anchor buddy: none of it helped in a lock and all of it cluttered the side decks where we needed clear space to move fast. Locking is a deck-handling job done at walking pace but with no margin for a tangle underfoot.
A clear side deck and a well-drilled crew beat a cockpit full of gear every time. If only two of you are aboard, the division of labour matters: one tends the bow warp, one the stern, and you swap the boat hook between you. The same shorthanded thinking that helps at sea, set out in the short handed deck gear piece, applies in a lock, because a flight of automatic locks with two people is its own rhythm.
Rigging the boat for the chamber
A few cheap modifications to the boat itself made the kit work better. Midships cleats or strong points, if your boat lacks them, transform locking, because a single spring line led from amidships holds the boat steady against the chamber wall while the water moves, far better than fighting bow and stern lines separately. On a barge with proper bollards this is no issue, but a converted sailing boat often has cleats only at the ends, and adding a midships point pays back in the first lock.
We also rig a couple of cockpit-height fairleads or just smooth turning points so the warps run cleanly from the crew's hands to the cleat without snagging on stanchions. A fouled warp at the moment the lock starts filling is how boats end up pinned or heeled against a wall.
Keep the engine running and in gear-ready throughout, even in an automatic lock, because a touch of throttle holds the boat off the wall or against the cill far more reliably than muscle on a warp. The boat hook and the warps tend the boat; the engine controls it. Mixing those two up, trying to hold a heavy boat with line alone, is the commonest beginner mistake in a French lock and the fastest route to a rope burn.
The kit list, short version
Four 15-metre soft warps, two 25-metre lines, two boat hooks (one long telescopic, one short), fenders rigged low plus a fender board and a couple of tyre fenders, grippy gloves for each crew, and a clear deck to work on. That covers a season of French locking, and almost all of it came in under a couple of hundred euros.
The canals reward boats that are set up for slow, repetitive, hands-on work rather than for survival at sea. Once you accept that and kit for the chamber rather than the ocean, the locks stop being a fight and become the best part of the day, which is roughly when the daily life on french canals rhythm takes over and you stop counting them.
