OK - down to the anchoring results. Now I've been working on this for over a year, but there is still more to be learned. As I do learn more, I'll happily update this thread.
Right now, this is good for average sized monohull sail boats from 40' and below.
ANCHORS ARE IN THESE BASIC CATEGORIES
LIGHT: Danforth, Fortress, West
PLOW: CQR, Delta, Bruce
*EDIT* NEW GENERATION: CQR, Bulwagga, Buelgel, Rocna (STILL TO BE TESTED)
And let’s call the fourth (for now) “OTHER” with the Mushroom, Fisherman, Kedge, Herreshoff, Yachtsman and Grapnel heading up the popularity contest in the group
**I don’t consider Drogues, Drift Socks, Buckets or Warps as anchors here. I have tested and compiled all of this over physical things that connect your boat to the bed of the ocean or lake and stick you there.
A little bit about each one, then we can move on.
Lightweight anchors started with the Danforth Design, which has long flukes and cants to about 33 degrees, but has a pivoting shank so that it folds flat. Because you get a lot of bang for the pound on lightweight anchors, they are popular. Danforth used steel, but the Fortress used a strange mix of aluminum alloys. Not only would the Fortress have two settings of about 45 degrees and 32 for different bottom types, it would also hold about twice as strong as any other lightweight anchor in most conditions in my tests.
It is noteworthy that the Fortress costs about twice as much as the Danforth, however, the load ability per dollar was nearly the same when comparing the weights of anchors to holding power. Also, I didn’t find the “reset” of these anchors too kind when the wind changed. A 180 degree wind shift would let the boat lie ahull to the wind for over 100 yards before they reluctantly dug back in. I didn’t feel safe using these, but keep the Fortress up on deck still for a kedge or secondary on 15’ of chain and 200’ of rode.
Plow anchors are aptly named after their farming cousins and how they work.
The CQR is by far the most popular and costly in this category because of its ability to both have a hinged shank to dig deep and workability in almost all conditions from mud, sand, rocks, plants, unsuspecting sea creatures, and your toes. The hinge seemed to help dig the anchor even deeper as winds grew and loads increased. This was a difficult anchor to handle on deck as it flops around in your hands while seas are rough, but hung from the bow roller well without clanging around. This anchor dragged for 50 yards before resetting in a wind shift. For inland sailors, that could be the difference between your hiding spot in the lee or running aground.
The Bruce is a Scottish design that I believe was developed by some guys looking to anchor some oil prospecting boats in the nasty seas up north. This was all cast steel, the cost was low and the holding strength was almost equal to the CQR. Because it doesn’t flop about, it is easy and noise free on the bow rollers or deck handling in rough seas. It dug in and held strong EVEN ON SCOPES OF 2:1 when I set it in cramped moorings and it held fine in 15-20 mph of wind. It sets FAST AND HARD into rocks, sand, mud, seaweed, and this odd calcite like rock we ran into one night. The Bruce is easier to retrieve than any other plow I tried. It promptly reset in just a couple of feet when the winds shifted.
The Delta shares the blades of the CQR without the hinging action. It handles nicely on deck like the Bruce, sets just as fast and deep, but was more difficult to retrieve in rock and weeds. The cost of the anchor is prohibitive and I didn’t care for it.
Other anchors I only minimally anchored with was the mushroom, Herreshoff, and Grapnel. NONE of these anchors were any good for use aboard a regular vessel barring a few exceptions.
The Mushroom might be a good anchor for slowing drift in a river for fishing. It was lost in rocks. It had no penetration in sand, mud or weeds. The Herreshoff was a loaner. It worked wonderfully in rocks but sucked everywhere else. It was easy to retrieve from the rocks with a trip line. The grapnel I think is a joke by someone who wanted to sell something funny to boaters that was completely useless.
Rodes and anchor sizes: I used synthetic braid for stretch, a foot of coated chain for every foot of boat with appropriate coating and Working load limit, and then the anchor sized according to manufacturer charts.
Weather Conditions: I did not intend this guide to include hurricane strength winds. The highest we observed was 38 Kts for about an hour. This should, therefore, be a good guide for “normal to slightly hairy” conditions.
Your complete anchoring system, or ground tackle depends on several things. AGE is the first. Don’t loose a few hundred bucks overboard or wind up with your boat on the shore because you bought an expensive anchor but tied it on old cheap ass line and chain. This is the “parking brake” for your expensive sailboat!!!!
Second note, is to learn how to properly use thimbles, swivels, static loading charts, and so forth. You cannot use an anchor lashed to a chain and tied to the nylon with a square knot or bowline. The rig should go something like this: Anchor-Shackle-Chain-Shackle-Swivel-Thimble carrying your 3-Strand on an eye splice, then up on deck, thimble or shackle the tail of your anchor rode to the deck or inside your anchor locker with the ring provided (most boats have them in there somewhere). Common sense dictates you should never have a loose end on your anchor line.
If you’re an “all chain” guy, you should go no less than 3:1 scope and always use a snubber line shackled into your chain. The shock loading is incredible with chain and it tore off a Sundowner’s winch out of the deck after seizing the gypsy when we were out testing. (I did chuckle a bit about a 41’ power boat loosing all that gear – money does not equal brains)
I used the formula from the Captains Course for the wind induced drag equations:
D = C * Fa * A * V2
D= Drag as Pounds
C= Coefficient (humidity, density, etc. were estimated from the book)
Fa= Area Factor (Size and Shape of type of boat) Use 0.75 for a dinghy or low freeboard racing boat, 1.0 for most boats anchored from the bow or stern and presenting no hull to the wind, or 1.5 for anchoring from the bow with a line to angle the hull towards the wind, or a bow anchored that swings into the wind (Kiting)
A= Area as beam times height (no rigging) expressed in sq. ft.
V= Wind Velocity in knots
C= A mysterious number for current and waves in which many publications vary upon, and I used the most common one, which is C= 0.009 since we are using non-metric factors here.
OK – it was hard to make a chart that fit and worked on the board here. A “Lunch Hook” is usually 15 kts, “Overnight anchor” is 30 kts, and let’s call a “Storm Anchor” 40 kts.
Generally, here is a selection of pre-completed factors. If your boat is say, 25 feet, you can simply interpolate the figures to get pretty close. NEVER FORGET Pressure on your ground tackle increases at the SQUARE of wind velocity so it is not very linear. Even a 20’ boat in a gale could see as much as 1600 lbs of force!
Winds 15, 30, 40 Kts
Factor 0.7, 1.0, 1.5
Force Applied is 45, 180, 360lbs at 15kts
Force Applied is 65, 260, 510lbs at 30kts
Force Applied is 97, 900, 760lbs at 40kts
Winds 15, 30, 40 Kts
Factor 0.7, 1.0, 1.5
Force Applied is 109, 440, 860lbs at 15kts
Force Applied is 120, 660, 1220lbs at 30kts
Force Applied is 240, 940, 1830lbs at 40kts
Winds 15, 30, 40 Kts
Factor 0.7, 1.0, 1.5
Force Applied is 180, 740, 1400lbs at 15kts
Force Applied is 260, 1050, 2100lbs at 30kts
Force Applied is 390, 1580, 3100lbs at 40kts
Ok, so why is applied strength important? It not only helps you choose the right anchor or bed to ground into, but also shows you how good your knot tying, splicing or line strength is. Most lines break at the knot, however if you do use the correct splices and knots, your line could separate in the middle, causing sudden breakaway and possible damage to your hull or deck.
Here is another chart I found on Three Strand to help you select the right size and why SCOPE IS SO IMPORTANT:
Inches, Average Breaking Strength, Working Load Limit at 5:1 scope and WLL 9:1 in pounds
3/8 3800 430 770
1/2 6800 760 1360
5/8 10580 1180 2120
3/4 15140 1680 3030
Overall, what’s the best anchor?
Well, that is not too simple to answer; there is not a “best” anchor for all situations, so I ended up carrying a Bruce and a Fortress on my double bow roller, with a foot of chain for each foot of hull length shackled and swiveled to 300’ of 1/2” 3-strand nylon on my 30 foot sailboat. I used the next closest (rounding up) anchor listed on the manufacturer’s chart for selecting the size.
On a 1-10 point scale (a total of 60 points is maximum), here is how I believe they stack up:
Cost / Value: 3 Set / Reset: 4 Sand: 7 Mud: 7 Seaweed: 6 Rocks: 4
Cost / Value: 4 Set / Reset: 7 Sand: 7 Mud: 9 Seaweed: 6 Rocks: 5
Cost / Value: 3 Set / Reset: 2 Sand: 8 Mud: 7 Seaweed: 3 Rocks: 1
Cost / Value: 7 Set / Reset: 10 Sand: 8 Mud: 9 Seaweed: 6 Rocks: 5
Cost / Value: 6 Set / Reset: 2 Sand: 5 Mud: 5 Seaweed: 2 Rocks: 1
Cost / Value: 10 Set / Reset: 1 Sand: 2 Mud: 2 Seaweed: 1 Rocks: 1
Cost / Value: 2 Set / Reset: 6 Sand: 1 Mud: 3 Seaweed: 5 Rocks: 9
Cost / Value: 5 Set / Reset: 1 Sand: 1 Mud: 1 Seaweed: 2 Rocks: 2
So now you should be in the ball park for starting to select your gear! I’ll be sure to add to this thread as I learn more!
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Last edited by Lancer28; 07-23-2008 at 05:13 PM.