nomadwilly wrote:Marin,
1. Brian didn't even mention the roll bar. How could he be incorrect about the roll bar when he didn't even mention it?
2. Marin wrote that Smith said*** ..."He says he took the roll bar idea from the Bügel.".... Are you saying we should believe what Peter Smith said?
1.* Brian said the Rocna copied the Sarca which copied..... etc.* The roll bar is common to both the Rocna and Sarca so I assumed that Brian was including the roll bar as part of the Sarca design the Rocna supposedly copied.* It's certainly the most distinctive design feature of both anchors.* Any other commonalities are pretty subtle after that one. So I would have thought that if Brian wasn't including the roll bar aspect of both anchors he would have said so.* But perhaps I assumed wrong.
2.* Well, where to you draw the line?* At what point should what a person says not be believed?* When should people not believe what you say, or what I say, or what anyone else says?*
Peter designed the Rocna initially for his own use (he says), and he said (in print) that he took design features he liked from several different existing anchors and refined them with his own design changes.* He said he got the idea for the rollbar from the Bügel.* I'm not sure I see any reason to disbelieve him.* I would be skeptical if he'd said he was the first person to ever think of using a rollbar on an anchor, given that the Bügel pre-dated the Rocna by a number of years.* But he didn't.* So I'm curious what it is about Peter's statement about where he got the idea for the rollbar that you find suspicious?
If you're interested, and if you haven't read these already, here are two article excerpts where Smith talks about the Bügel.
1.______________________
The Bügel, developed in Germany by Rolf Kaczirek, is the first of the new generation anchors, and it pioneered a novel configuration involving a semi-circular roll-bar. The weight of the fluke rolls the anchor about the roll-bar, pivoting on the shank end. The Bügel is very primitive, consisting of:
A straight bar shank
A roll-bar to turn anchor
A flat fluke with sharp tip to gain rapid penetration
It represents a good development on most old generation anchors, except perhaps the Delta in some circumstances, but is hampered by its simplistic configuration and non-optimized design.
[the article continues]
The Rocna was developed by New Zealander Peter Smith in 2000, released commercially in 2004 following strong demand developed from early models produced privately for Smith and friends. The Rocna uses a roll-bar like the Bügel, and develops the rest of the anchor to a far more sophisticated level. Both the shank and fluke are carefully optimized in order to maximize efficiency, with an eye to strength and durability. The Rocna consists of:
A concave fluke similar in form to that of the Spade but with more surface area
Tip-weight in the form of a thicker tip section, which keeps the tip profile slim while adding strength to the tip
Skids to assist with setting
Sensible shank designed to minimize early setting resistance and enable practical stowage on bow rollers.
2._________________________
When asked if Mediterranean charter operation Yildiz Yachting had problems with holiday-makers dragging their anchors, Kees Verboom replied "We used to. We often had to repair boats that were damaged on rocks after [the] anchor dragged. But since I changed the whole fleet over to German Bügel anchors, theres been no problem."
Others have invested in the more costly Spade, the anchor from Tunisia designed by Frenchman Alain Poiraud. John Harries and Phyllis Nickel on Morgans Cloud, authors of the Norwegian Cruising Guide, recently wrote an article in Cruising World about their upgrade to two Spade anchors, saying they had effectively solved all their old anchoring problems in their high-latitude cruising grounds.
"Ploughs are designed to divide the seafloor the planar Bügel will resist more than a simple wedge [plow] and the concave shaped Spade will resist the most." Adrian Faulkner discussing which shape an anchors fluke should be; convex, flat, or concave; in Practical Boat Owner.
Yet, as good as the Bügel (AKA Wasi) and the Spade are, there was room for improvement, and the Rocna in a simplistic sense represents the best of both. It has a roll-bar like the Bügel, which guarantees the anchor achieves the correct attitude every time it hits the bottom. The Rocna also has a concave fluke shape, like the Spade, aiming for the optimum resistance given by the spoon form, which maximizes holding power once set.
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*
-- Edited by Marin on Sunday 6th of February 2011 10:59:44 PM
