Anchor Size

[Orion Jim]

Originally Posted by Mike OReilly

So... right off the bat I would ignore any sizing chart that lumps such a huge ranges (33-49 feet or 30-40 feet) into one recommendation. Clearly they are not to be trusted.

Secondly, do yourself a favour and get a better anchor. Both these are poor performers compared to most modern anchors. Look at Rocna, Manson, Mantis, Excel, Spade, or other similar "new-gen" anchors. They are just better.

Finally, just ignore kmacdonald on this, and pretty much every other topic on this forum. It's a general rule most people learn. It will serve you well to learn it early.

Have to agree with everything stated here.....including that last part

[Shrew]

Originally Posted by eje

I wasn't trying to generate a metaphysical discussion on anchor sizing. I was just commenting/wondering out loud on the apparent difference in holding power of two anchors with similar shape -(other than the hinge)

Well, you title the thread "Anchor Size" then the scope within the body of the post is discussing anchor type and the question is about theoretical differences in shape/function.

What exactly did you expect to get for answers?

[Cheechako]

Originally Posted by eje

Anchoring.com has tables with recommended anchor sizes for various sized boats I do understand there is more to selecting an anchor than simply the length of the boat, but my question is this:

They recommend a 45.5# hinged CQR/Plow for a 33-49 ft boat, but a 30-40 ft boat only needs a 22# Wing/Delta. Other than the hinge these anchors are the same basic shape. Why would the same boat need a hinged plow twice the size of the delta?

Well, I dont know that site, but a hinged plow like a CQR seems to need more weight from my experience. Simply because often it's not well dug in at all. If you look at how a CQR hits and lays on the bottom, it seems to rest on it's side more often than not. This is because of the huge knuckle at the shank attachment weighs a lot and is up high. (poor center of gravity) It then drags readily until it buries just enough to hold... on it's side. Basically one fluke of the two.
A Delta, OTOH, almost always lands upright, It's bottom weighted to do that, & no knuckle) and digs in readily.

One difference though is that in a 180 degree wind shift, the CQR MAY hold with the shank flipped over, albeit not in a big blow.
The Delta holds great until a wind shift then pulls right out as the reversed pull just flops it over 180 degrees.

If you ask me that site is BS, those ratings are WAY WAY undersize. A 45 # CQR was fairly standard faare for a 32 Westail or etc. NO WAY on a 49 ft boat.
A 22# Delta MAYBE on a 30 ft boat, but no bigger.

[Tayana42]

Originally Posted by Mike OReilly

So... right off the bat I would ignore any sizing chart that lumps such a huge ranges (33-49 feet or 30-40 feet) into one recommendation. Clearly they are not to be trusted.

Secondly, do yourself a favour and get a better anchor. Both these are poor performers compared to most modern anchors. Look at Rocna, Manson, Mantis, Excel, Spade, or other similar "new-gen" anchors. They are just better.

Finally, just ignore kmacdonald on this, and pretty much every other topic on this forum. It's a general rule most people learn. It will serve you well to learn it early.

I also agree with everything said here including the last part!

Do not rely on any of the compilation charts or tables. Choose an anchor type and look at that manufacturer’s recommendations, then go up a size. There is a huge difference in the performance of new generation anchors compared to older designs. Some anchor manufacturers, Delta in particular, are known to undersize their recommendations so boatbuilders can save money on “standard” equipment.

I have had and used Danforth, original Bruce claw, original CQR, and two sizes of Delta anchors before settling on my current 53 lb Ronca for my 42’ sailboat. I couldn’t believe the difference the modern design made in setting and holding. I believe the new generation designs will all give you much better performance. And yes I too believe you should upsize your entire anchoring system (anchor, chain, roller and windlass) to the biggest you and your boat can reasonably handle.

[ranger58sb]

Originally Posted by eje

They recommend a 45.5# hinged CQR/Plow for a 33-49 ft boat, but a 30-40 ft boat only needs a 22# Wing/Delta. Other than the hinge these anchors are the same basic shape. Why would the same boat need a hinged plow twice the size of the delta?

Dunno... might be that site is presenting some kind of zen compendium of recommendations from each individual manufacturer... or maybe instead they invented some fuzzy math...

In any case, I can tell you we did not have perfect luck here in the Chesapeake mud with a 35-lb Delta on a previous 34' boat with "fixed windage" (aka powerboat with flying bridge).

-Chris

[Pegu Club]

Reference manufacturers sites for anchor size, if you are of the sort that anchors out in a variety of weather conditions, going up one size with appropriate chain/rode is the way to go. If you are going to purchase a new anchor, go with a “new generation” anchor, such as a Rocna, Mantus, etc. they set better than old style anchors and do so in a wider variety of bottom conditions. Do your homework and you will likely be fine.

Fair winds,

[sailorboy1]

Originally Posted by eje

Why would the same boat need a hinged plow(CQR) twice the size of the delta?

because those anchors aren't really anything like each other if you were to see them next to each other

[fish53]

Originally Posted by kmacdonald

My Fortress FX-7 (4 pounds) blows the doors off my Rocna 15kg (33 pounds) in soft silty mud.

That's interesting, I observed the same only it was FX-7 and a Mantus 25 lb.