Hi all,
I have some basic questions about anchoring overnight, hoping to ease my mind and give it a go this summer. I've been sailing my 10?m Crowther cat for a number of years and feel comfortable with it. I've done plenty of overnight stays, but only when there's an available mooring or at a marina. I'm a bit paranoid about sleeping at anchor until I've confirmed a few things.
My current setup is:
12kg Danforth Anchor
5m of 8mm chain
35m of 12mm nylon rope to the boat
Also, 20m of 6mm chain doing nothing. never used.
Whenever I anchor, it's just for a lunch stop in 4-8m of water, so it's pretty easy stuff. I lower and raise the anchor by hand, so 5m of chain isn't difficult to handle. I can run the rope up to a winch if needed. I also have a spare 20m of 6mm chain on board that's not in use.
I have a couple of questions:
Is 5m of chain and 35m of rope enough to anchor overnight in 3-8m of water? I feel maybe I should be using more chain.
The current setup would give me about a 5:1 scope in 8m of water, but I'm worried that might not be enough of that in actual chain?
Would I be better off ditching the 8mm chain altogether and just using the 20m of 6mm chain?
Another option could be to cut the 6mm chain down and attach only 10m of it to the end of the 8mm chain to give a total of 15m of chain. If that's suitable, could I simply join them with a 6mm bow shackle?
Any input would be greatly appreciated - as i'd like to gain more confidence in anchoring.
Thank you!
Hi BGR
RE: Is 5m of chain and 35m of rope enough to anchor overnight in 3-8m of water? I feel maybe I should be using more chain.
You have given your anchoring set up.
My current setup is:
12kg Danforth Anchor
5m of 8mm chain
35m of 12mm nylon rope to the boat
Also, 20m of 6mm chain doing nothing. never used.
I don't want to confuse the issue but there are other things to consider when anchoring (overnight).
1 What is the forecasted wind? Will it build or shift during the night?
2, What is the seabed? The makeup of the seabed will effect the original anchor set and any reset if the wind shifts and the anchor swivels or pulls out.
3 What are the geological features of where you are anchoring? Is it a sheltered estuary, a cove with surrounding hills or off an island or beach? Will the anchorage give you good shelter from the wind?
As for you set up, 5 meters of 8 mm chain is nothing. The more chain that you can lay on the (sound) seabed the better.
I would shackle on the 20 meters of 6 mm chain and the nylon rode to that. Have all you anchoring kit ready to go.
RE:I lower and raise the anchor by hand, so 5m of chain isn't difficult to handle.
A good bow roller is essential to raising the anchor by hand. Sit, brace your legs either side of the chain and haul ergonomically.
Some people spend a lot of time and money at a gym and some raise their anchor by hand.
RE: 12kg Danforth Anchor
The Danforth will do the job in sand and mud. Not reliable in rocky seabed or coral or grass. Anchors are expensive. However, I would look out for a fisherman's yacht anchor. Others might disagree, but, I like them and they are probably the only anchor that you will pick up cheaply. The fisherman's and the Danforth will give you a choice of anchors for a variety of seabeds.
I would probably leave the fisherman at home when day sailing and stow it aboard when doing an overnighter.
Hope this helps,
gary
Apart from getting the scope right for the conditions, what I do is have Navionics on a tablet and start the tracking and leave it on when you anchor. You should see a tight pattern when the vessel swings around and easy enough to see if you are holding or not.
I also use an anchor alarm but always check the tablet track pattern when I get up during the night.
Sean
12kg danforth might be a bit light, I carry a 20kg danforth for a kedge. Join all your chain & rope together & look at one of the more modern anchor designs, along with an anchor watch app for peace of mind
Select to expand quoteBGR said..
The current setup would give me about a 5:1 scope in 8m of water, but I'm worried that might not be enough of that in actual chain?
When calculating scope you have to include freeboard + depth. So if you have 1m height of roller or fairlead above water, then 5m depth plus 1m freeboard = 6m so anchoring with 5m of chain plus 35m of rope = 40m divided by 6 gives you scope on 6.7:1. In 8m of water your scope would by 40 / 9 = 4.4:1
As Gary says you should add more chain and also another type of anchor if you're going anywhere that doesn't have a sandy/muddy bottom.
I had the same quandry, only got danforth with the boat.
asked a friend who is v. experienced, as i didnt like the idea of danforth overnight. He lent me a plough with a heavy bit of chain.
Problem is, overnight wind will likely drop to nothing while boat is moved in whatever direction the water moves, so even if you dig in, very likely the boat will creep slowly to another position then when it comes tight, just release the anchor from the bottom.
Stick all your chain together with the 8mm at the anchor end.
Have a look on gumtree for a decent plough or better (i realise there are much better options but ploughs are common)
queensland this is cheap!!!
www.gumtree.com.au/web/listing/boat-accessories-parts/1339537239
victoria: looks like it might be quite big
www.gumtree.com.au/web/listing/boat-accessories-parts/1339511200
I have hurt my back raising the anchor without a roller. As Gary says.
I plan to stick a bow roller onto a plank with some padding (maybe a bit of rubber) and then temporarily mount the plank (maybe just lash) on the foredeck when raising the pick - so i can "row" the anchor up rather than leaning out over the pulpit to raise it.
I'd like more info to give a better answer. However,
'Problem is, overnight wind will likely drop to nothing while boat is moved in whatever direction the water moves..." that's normal at an anchorage but if you mean it is in a tidal area, then you can always set a second (i.e. additional) anchor. The anchors can be set at a V-shape to the bow, or 180 degrees apart.
I like the SARCA, Rocna, Bugel and similar hooped anchors; their reputation is better for re-setting and holding in more types of seabeds.
To solve paranoia when anchoring overnight, the answer is practice and practice, and ideally with calm-ish conditions and with the extra length of chain and/or heavier anchors recommended. Anchor overnight when there is no cold front forecast, when the winds are predicted to be below 10 knots all night, etc, so you don't expect to have testing conditions and stress.
I'd recommend having a second anchor, and one of them having about 15 metres of 8mm chain. That way, you have adequate chain rode and nylon, you have a second anchor as 1) back up and 2) at a different angle (60 degrees apart, or 180 degrees if tidal reversals), and practicing in benign conditions, and having a cold beverage in the evening, enjoying the sunset, calming your nerves and taking it all in, that there's no adverse wind or currents affecting the boat.
There are also plenty of articles and chapters in books about the various techniques/methods.
Sizing guide for a Sarca Excel anchor recommends a 16kg for 10 - 12mtr boat. I go up a size from recommended so would opt for the 22kg if it was me. I thought catamarans have more windage than a mono and generally go for a larger anchor for a given boat size too. I would go bigger chain and more of it as well.
Hi BGR,
A couple of handy metrics (apologies if already known).
You want an average of 6 x the depth of the water (+height of the bow roller from waterline) for your scope length.
For a rope/chain rode, the minimum length of chain is your waterline length. Personally, I'd double that.
The 6mm chain is a bit light, you'll be bouncing off of it all night in wind (think of it as all rope). I'd keep the 6mm for a seconday anchor or a kedge and stick to 8mm.
All the best to you!
Select to expand quotegarymalmgren said..
A Sarca Excel 16 kg anchor is $650 .
Not everyone can afford that,
gary
Not everyone can afford a 10mtr catamaran, I would go the 22kg
Just my opinion, anchoring is serious, having undersize gear is dangerous. I think its right to be a bit paranoid about a 12kg anchor on 5 mts of chain for a 10mtr cat, I would be too.
All the above advice about technique and conditions etc is all very good however it all depends on having a sufficient anchoring set up in the first place. Your missing out on the potential of the boat and diminishing the enjoyment if you cannot anchor safely and confidently.
The other issue is an emergency, its great to only use moorings or marina's but what if something goes wrong on the way, it can sometimes happen on a boat
, a 12kg anchor may not keep a 10mtr cat off a lee shore in blow with a bit of sea state.
At $650 its probably less than 1% of the value of the boat for a one off purchase. Spend a few % and get 90mtr of 10mm chain and a windlass too. As an investment its a no brainer, you gotta have the right anchoring gear, that's basic seamanship imo. Imagine the conversation with the insurance company when your making a claim as a result of not being able to stay anchored.
BTW its crazy when you see a boat washed up on a beach with the anchor on the bow, what is with that. There was one at Kings Beach on the Sunny coast a few days ago, high and dry and the anchor is on the roller.
Hi again, and thanks for all the responses.
To add a little more information to my post: all of my anchoring is on sand in and around Port Stephens, Lake Macquarie, and Pittwater. Nothing too extreme, and during the day the Danforth anchor has worked quite well.
However, I've never experienced a full 180-degree wind direction change while using it.
From the replies, it sounds like I'd be better off moving to a plough-style anchor and possibly running around 20 m of either 8 mm or 10 mm chain.
A quick Google suggests that 10 mm chain would add roughly 30-40 kg more weight than 8 mm over 20 m, which would be additional weight on the bow of my cat, along with a heavier anchor.
I already have a bow roller installed.
Thanks again for all the replies - they've been a great help.
Select to expand quoteBGR said..
Hi again, and thanks for all the responses.
To add a little more information to my post: all of my anchoring is on sand in and around Port Stephens, Lake Macquarie, and Pittwater. Nothing too extreme, and during the day the Danforth anchor has worked quite well.
However, I've never experienced a full 180-degree wind direction change while using it.
From the replies, it sounds like I'd be better off moving to a plough-style anchor and possibly running around 20 m of either 8 mm or 10 mm chain.
A quick Google suggests that 10 mm chain would add roughly 30-40 kg more weight than 8 mm over 20 m, which would be additional weight on the bow of my cat, along with a heavier anchor.
I already have a bow roller installed.
Thanks again for all the replies - they've been a great help.
Where are you? There's a number 5 Sarca Excel on facebook "Aussie Yachties Buy Sell Swap" for 200 bucks. It's queensland.
There is something to said about the sound sleep I get from a modern anchor combined with the Anchor Pro App.
Maybe if your going somewhere sheltered in Pittwater initially with a favourable weather report just set the anchor and use a Anchor App to learn how the boat moves at anchor.
It is great to be able to see the track of the boat after any wind shift or increase. You can see the results of the reset and bedding in of the anchor in real time. See the picture for an example, that night the wind must have been consistent, the bit below the main blob may have been me walking to the stern to fish with the phone in my pocket. Unfortunately I haven't screen shot the results after a reset or large wind shift.
Much nicer than trying to take bearings at night on a swinging boat to determine if your dragging.
Watch Marketplace or similar and a suitable SARCA or Rocha will appear, easy way to remove any paranoia.
