Solved windlass problem

[Dockhead]

Just spent a week, more or less, on the boat, with a little time off for business in London.

Finally solved a problem with the windlass which has been bothering me for a year, and I thought I would share the solution in case anyone else has a similar problem.

I have a Lewmar Concept 3 vertical shaft windlass on my boat. The motor drives the gypsy via two cone clutches. The cone clutches consist of a bronze cone each, and a conical friction surface on each side of the chain gypsy. The gypsy is chrome plated and the cones are bronze.

My problem was that the chrome started flaking off the upper friction surface in the gypsy. It started slipping and I couldn't tighten it down (using a winch handle in the top nut of the windlass). So last week, I took out the gouged up upper cone to a machine shop and had the mating surface cleaned up, and 50 thousands of an inch milled off the bottom face so that the cone would not bottom, thus preventing the conical mating surfaces from mating.

I put it all back together and it seemed like it should be dandy. But when we sailed into Studland Bay in pitch darkness on Friday night intending to anchor, I decided to check it, and it was not holding at all. When I tried to tighten it up, the shaft merely spun. I tried to tighten it up by operating the motor, but the top nut just spun. In despair, we diverted to Poole, where the town quay marina was closed for the night, and snuck into an empty slip.

I figured there must be something broken in the drive system -- shouldn't the shaft be fixed to the motor? How could it just spin like that? Did I strip the threads in the top nut? The threads were not stripped, and I decided as a desperate measure to add another washer to the plastic washer between the top nut and clutch cone. I didn't understand why it might work, but it seemed that since 50 thousands had been milled off, maybe the nut wasn't clamping down on the cone. Although why this would be so I didn't know.

I couldn't find a washer of the right size, but found something that slightly fit. Put it on and -- Eureka! Tightened down so hard that I broke (!) a plastic winch handle.

We then sailed to Worbarrow Cove and successfully anchored in the Eastern end (Where incidentally I tried to anchor at least 10 times last year with the old Delta anchor and never got any holding -- the Rocna set first time and held up to a full power test pull!! How great it is to have confidence in your ground tackle! The wind kicked up overnight and I just stayed in bed!).

In the morning, the windlass just wrenched the anchor out of the seabed without slipping an iota. I never knew how powerful the windlass was since it has slipped since I bought the boat almost two years ago. We were anchored in about 10 meters of water with 80 meters of 12mm chain out -- that's the better part of a thousand pounds of ground tackle including the 121 pound Rocna. The windlass made mincemeat out of it.

So for anyone who has had any similar problem with a windlass with cone clutches --

1. Make sure you've got enough washers under your top nut to clamp down on the clutches.

2. If your conical surfaces start to wear, you may need to mill something off the bottom of your clutch cones, so they don't bottom out.

[gbanker]

thanks for posting......

[Blue Stocking]

Good information to keep in mind.
One would not normally think that the quality of metal to metal mating surfaces would be so important, but obviously they are.

[btrayfors]

Dockhead,

Glad you found the problem.

However, your statement that "the windlass just wrenched the anchor out of the seabed without slipping an iota" suggests that you may be expecting too much of that Concept 3.

I have a Concept 2, by the way.

Windlasses are NOT designed to "wrench anchors out of the seabed" or to do any other really "heavy lifting". They are designed to raise the anchor and chain AFTER the anchor has been dislodged from the bottom, using the engine or sails.

The proper way to do it is to get the boat as close over the anchor as possible and then, using the engine or sails, break the anchor free of the bottom.

Improper use of the windlass may be why you had problems in the first place.

Bill

[Dockhead]

Originally Posted by btrayfors

Dockhead,

Glad you found the problem.

However, your statement that "the windlass just wrenched the anchor out of the seabed without slipping an iota" suggests that you may be expecting too much of that Concept 3.

I have a Concept 2, by the way.

Windlasses are NOT designed to "wrench anchors out of the seabed" or to do any other really "heavy lifting". They are designed to raise the anchor and chain AFTER the anchor has been dislodged from the bottom, using the engine or sails.

The proper way to do it is to get the boat as close over the anchor as possible and then, using the engine or sails, break the anchor free of the bottom.

Improper use of the windlass may be why you had problems in the first place.

Bill

I agree with this. I was testing the windlass after repairs. It's not my usual technique.

Like most of us, I use the windlass to take up slack in the chain and haul the anchor up, not to move the boat by brute force or rip the anchor out. When it's not blowing too hard, I like to take the slack out little by little and let the catenary move the boat. I find by being patient and letting the boat settle in after every 5 or 10 meters of chain, it will produce its own slack better than the helmsman can by guessing where the anchor is. If it's blowing, obviously you have no choice than to motor over the anchor.

Then when the boat is right over the anchor and the chain is vertical, I like to take out the last bit of slack inch by inch as the boat bobs up and down. Then the boat pulls the anchor out with its own motion. In stubborn cases, I tie off the anchor chain (so the force is not taken by the windlass), and motor forward in the opposite direction to how the anchor was set in the first place, to break out the anchor.

In my case this is almost never necessary. If you work out the slack very patiently, inch by inch, the boat will almost always pull the anchor out by itself without any motoring being necessary. It takes more time but I think it is more gentle on the gear.

I suppose most of us do the same thing

[btrayfors]

Originally Posted by Dockhead

I agree with this. I was testing the windlass after repairs. It's not my usual technique.

Like most of us, I use the windlass to take up slack in the chain and haul the anchor up, not to move the boat by brute force or rip the anchor out. When it's not blowing too hard, I like to take the slack out little by little and let the catenary move the boat. I find by being patient and letting the boat settle in after every 5 or 10 meters of chain, it will produce its own slack better than the helmsman can by guessing where the anchor is. If it's blowing, obviously you have no choice than to motor over the anchor.

Then when the boat is right over the anchor and the chain is vertical, I like to take out the last bit of slack inch by inch as the boat bobs up and down. Then the boat pulls the anchor out with its own motion. In stubborn cases, I tie off the anchor chain (so the force is not taken by the windlass), and motor forward in the opposite direction to how the anchor was set in the first place, to break out the anchor.

In my case this is almost never necessary. If you work out the slack very patiently, inch by inch, the boat will almost always pull the anchor out by itself without any motoring being necessary. It takes more time but I think it is more gentle on the gear.

I suppose most of us do the same thing

Yes, excellent technique. All of it. I do exactly the same, after more than 50 years of anchoring in many locations around the world!!

Cheers,

Bill