I found the following comparison study of a Manson Ray, Manson Supreme, and Rocna. It's for very heavy anchors, however it's very interesting info:
Practical%20Sailor%20Large%20Anchor%20Tests.pdf
That test was conducted by a cruising couple (whom we know well) in southern Chile, it had nothing to do with Practical Sailor before it was sent in to them. It was done in the middle of winter and the beach was frozen hard. They had no load cells, no way of really controlling the pulls, used the windlass on a yacht, etc. The writer is a known proponent of the Bruce type, and the Manson anchors supplied to him (including their Bruce type) were given to him at no cost. He had to pay for the Rocna. Most magazine reviews/tests on anchors are essentially bogus, the only (and I do mean only) test of recent years that approaches validity is the West Marine 2006 comparison which Al mentions below.
Some posters have warned about the use of ss anchors. Plastimo is a Navimo company as is Manson.
Navimo is the US face of parent Plastimo (France). Navimo is the US distributor for Manson, they have no other connection. Manson is a New Zealand company about 10 mins away from me right now
who produce knock-offs of five different anchor styles including the Bruce.
Would someone please write the following marine equipment suppliers and/or manufacturers and notify them that they are putting sailors in harms way because of the stainless steel equipment the sell and/or manufacture, i.e. anchors, shackles, swivels, chain, etc.:
Defender Marine, Fisheries Supply, Lewmar, MariSafe, Manson, Plastimo, Rocna, West Marine, etc.
You appear to have missed my point re the cost of quality marine stainless. 316L is costly. By the time SS is of sufficient tensile strength for use in anchors (in our view), it is
extremely costly. The problems such as they are come from the cheaper products which use poor quality steels and inadequate working/finishing. Stainless properly done is okay.
Take a look at this:
www.rocna.com/images/remote/rocna-55-stainless-gallery.pdf
If you can't see much difference, that's okay, the point is it's there. That was an NZ$8,000 anchor several years ago, when the exchange rate made it about US$6,000, and was about as cheap as we could do it without compromising its quality.
As to the companies that are happy to make such compromises, well, you can write to them if you wish. Unfortunately you have already voted the opposite, with your wallet, and this speaks more loudly than letters. The reality of the situation is that large anchors (get much over 70 kg) generally require classification and certification - the authorities care about commercial operations and the like - so there is already some regulation in place, but this does not extend to the small boater. You are mostly on your own - buyer beware etc. The small boat building industry is not sufficiently developed, like the automotive or aeronautical industries for example, for every little detail to be taken care of for you. (Of course, you can still go out and find brake pads made from sawdust, if you really want to save those pennies).
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I notice from Rocna's latest (press_0612_wm_ym_testing.pdf) that both the Rocna and Mason held to 5,000# twice, while the Delta only did so once.
However, the Delta's other 3 graph bars were about twice the height (3,000# holding force, vs 1,500#) of both the Rocna's and Manson's 2 non-5,000# bars.
(The Spade held to 5,000# 3 times, but its 4th 500# bar gives me the willies. My Fortress looks wonderful, until I consider re-setting - a concern in tidal rivers that such testing ignores.)
It appears from this test (and from the earlier testing PDF on the Rocna web-site) that the Delta is superior (by quite a bit) to the other (non-rollbar) anchors, and represents an "almost there" evolution that has now been succeeded by the still-more-advanced Rocna/Manson design.
Having had good luck with my 35# Delta (and 300ft of 5/16 G4 chain) in much more limited experience than many of you, I was considering a 44# Delta for increased confidence (15k# 36ft boat), but attracted by the Rocna.
Based on the test results, I'm having a hard time reconciling the additional expense of a 33# Rocna. (Arguments about holding power from smaller sizes make me uncomfortable sacrificing pure brute weight.)
Why no comments on Deltas?
Al your reasoning is quite correct, although we would rate the Delta as behind the Spade also. We should know, we used a Delta from the UK to New Zealand
We are intimately familiar with its problem characteristics, which formed the early incentive for the Rocna. The Delta will (sort of) hold its own in simple scenarios, but it starts to fail you in more varied conditions. The cost issue is really down to production, even with the galvanized models.
What I'll do is link to the Rocna Knowledge Base article on the Delta, take a look at the little essay by Peter at the bottom:
www.rocna.com/kb/Delta_anchor
