LM 32 swinging on anchor

[andres]

I have experienced that my LM32 is swinging on anchor a lot.
In winds more than 15-20 knots the boat swings 90 degrees in one direction, then when the boat pulls on the anchor it turns and swings 90 degrees into the other direction.
I have a bridle connected with a chain hook from both cleats to the chain.
It swings much more than other boats in the anchor field and therefore I need much more space around me than other boats.
That make it difficult in tight anchor fields with many boats.

Any idea to prevent heavy swinging on anchor ? 

[johnc]

I have just bought an LM28 (mini version of the LM32) I have not had the boat in the water yet as lot of work to do but I may have a suggestion based on an item I found in the cockpit locker.

It is a very heavy weight (25 lbs) called an "angel" which is slid down the anchor chain on a rope to few meters above seabead. This gives the advantage of setting out less chain as the weight keeps the pull on the anchor more horizontal. It also hold more of the chain on the seabed.

A lifetime ago (1960s) my Dad always insisted we set the Angel when we were setting the anchor on his motorcruiser which had a lot of windage.

Hope this may help.

[chrismunson]

The pilot house structure is a sail, and these boats do sail back and forth thru an arc of 45 degrees, or more. No matter what you do with one anchor, the swing will not stop in a breeze. You could deploy 2 anchors set about 45 degrees apart, but this will fail in a wind shift, lays out a snare for passing boats, and can get tangled and be a real mess to recover, clean and stow.

A riding sail, hanked to the back stay and pulled tight, is a good solution. The sail is about 6 feet on each leg, and is rigged once you've anchored. Sailrite sells a kit that's very affordable. We've used one in 30 years of sailing, and it reduces the anchor waltz to practically nothing.
Sailrite' Manual is attached. Set to sail to one side of the boat, not on the center line, or it will flop back and forth all night.Using An Anchor Riding Sail.pdf (205.31 KB)

[mudberth]

Oct 2, 2019 10:08:32 GMT andres said:

I have experienced that my LM32 is swinging on anchor a lot.
In winds more than 15-20 knots the boat swings 90 degrees in one direction, then when the boat pulls on the anchor it turns and swings 90 degrees into the other direction.
I have a bridle connected with a chain hook from both cleats to the chain.
It swings much more than other boats in the anchor field and therefore I need much more space around me than other boats.
That make it difficult in tight anchor fields with many boats.

Any idea to prevent heavy swinging on anchor ? 

[chrismunson]

lmowners.proboards.com/post/2297

[chrismunson]

Here is a complete and informative article about riding sails.

www.sail-world.com/Australia/Use-the-Magic-of-a-Riding-Sail-at-Anchor/-88348?source=sail-world





Does your sailing boat always lie steady as a rock at anchor? Or does she tend to wander back and forth like a restless mare in a corral? There are several ways of overcoming this, the best known being to use an Anchor Buddy or Sentinel (see www.sail-world.com/index_d.cfm?nid=38056!story). However, there's another excellent solution, and John Jamieson (Captain John) of skippertips.com shows this little-known technique that will help cure the problem fast and easily!

Some boats behave themselves while on the hook, while others will sway back and forth from side to side. This action--called 'sheering'--can put a lot of side load on the anchor shank. In some conditions, this could cause the sailboat anchor to break free and the boat to drag her anchor! Just the thought of this could cause you a stressful night on the hook--instead of a peaceful, tranquil one.

With twin backstays, sheet the riding sail almost flat to one side of your boat.

Three factors can lead to sheering and heavy ground tackle loads...

* Ocean Ground Swell
When ocean swell break on a sand bar, they expend their energy and die a quick death.

But some islands have smooth beaches. Instead of breaking, the swell wraps around the island's windward side and creates a ground swell on the lee side.

This results in an uncomfortable 'rock 'n roll' motion for anchored boats. Look for islands with deep coves on their lee sides for better protection.

* Freeboard and Windage.
Sailboats or power boats with lots of freeboard (the distance from waterline to the deck) present more surface area for the wind. Also, boats with lots of canvas--enclosures, Biminis, and dodgers--create excessive windage. Lower as much canvas as possible to reduce windage.

* Light or Beamy Hulls.
If you cruise or race in a lighter than normal hull, it will tend to sheer from side to side at anchor, even in light winds. The same goes for hulls with extreme beams, like catamarans and trimarans.

Enter the Riding Sail!

The riding sail looks like a pint-sized storm jib and hoists on the backstay. It acts like a weather vane on the roof of a barn to keep your bow pointed up into the wind at anchor. Follow these five steps to get your small cruising boat under control fast with this magic sail:

1. When to Hoist a Riding Sail?

Hoist your riding sail whenever you drop the hook. This becomes more important in windy anchorages. But even in lighter winds, it will help keep your boat's bow into the wind and under control.

2. Pick the Best Sailcloth Weight.

Choose heavy 6 oz. to 8 oz. sailcloth. Ask your sailmaker to hollow (concave) the leech and foot. This keeps flutter down. Veteran cruisers Steve and Linda Dashew recommend full length battens with extra heavy reinforced batten pockets. In high winds, this controls flogging and extends the sail's life.

3. Determine the Size You Need.

Sailboat ketches or yawls should reef the mizzen and use it as their riding sail. For sloops and power cruisers, use the sizes below, recommended by Sailrite. In a pinch, you could hoist a small storm jib on the backstay, as long as it lies within these sail area parameters:

Sailboats up to 35’ = 12.5 sq. ft. riding sail
Sailboats 35’ to 50’ = 20 sq. ft. riding sail

4. Hoist Away on Your Backstay.

Make a pendant that attaches to the deck near the backstay. Have your sailmaker make the pendant from wire rope with eyes in each end, or you can use low-stretch line (Dacron, Spectra) as a pendant. Hoist the riding sail with the mainsail halyard about 1/3 of the way up the backstay. This keeps the riding sail out of the way of crew in the cockpit. If your vessel has a split backstay, hoist on one side of the backstay and sheet the sail flat on that side (see picture).

5. Sheet to One Side.

Lead the sheet through a snatch block or Genoa sheet block on one side of your boat. Sheet the sail almost flat and belay (cleat) the sheet. Sheeting the sail flat reduces flogging (the #1 killer of sails), keeps the bow under control, and helps prevent sheering in shifty winds.