Bügel anchor

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Generic Bügel pattern anchor.

The Bügel is a simple fabricated anchor design developed by a German in the 1980's. It features a flat triangular fluke with a straight shank, and a roll-bar to orient the anchor correctly. German steel firm WASI produce a stainless steel version, and other Bügels are produced in amateur capacities.

The Bügel design happens to work quite well in weed, which has made it popular in Europe and Turkey. It was the first anchor to have at least partial success in the weed mat sea floor synonymous with areas such as the Mediterranean.

The design is also very easy to build, which means that cheap knock-offs are readily available in most countries, especially those in the Mediterranean. The design was patented but it seems the intellectual property was never defended, and has since expired in any case, and these knock-offs are just collectively referred to as genericized "Bügels".

"Bügelanker" translates from German to "roll-bar anchor". Nb.: "Bügel" is correctly circumscribed as "Buegel" if typing the umlaut ü is awkward. WASI produce a version which is branded the WASI Bügelanker, and this name is frequently shortened to just "WASI", particularly in the USA.

If a Rocna is compared to a Bügel, it will be seen that the Rocna is a far more sophisticated design. Begin with a sheet of steel, cut a triangle, attach a half-pipe to the rear, weld on a straight bar for a shank, and you have yourself one Bügel. It is very primitive and the roll-bar is really the only similarity with the Rocna design. The straight bar shank of the Bügel creates problems when stowing on a boat's bow (it is hard to pull home properly). The Rocna has a carefully shaped concave fluke, it has much more tip-weight (the toe is thicker than the heel) to aid setting, it has the skids to further assist setting, and the shank is both a much more practical design and far stronger.

A properly built Bügel (many are thrown together in ignorance of the design's important points and don't perform as well as they should) will work fairly well in weed, at least better than plows and claws. They also offer a bit more fluke area than the older types of anchors, meaning they generally are superior. It is important to note the quality assurance problems with any Bügel anchor – other than the stainless steel WASI, there can be little guarantee of build quality, and many of these anchors are knocked out by fabrication shops or amateurs who possess no expertise specific to anchors and do not understand the design. A Bügel knock-off built by a fabricator in New Zealand was tested by ourselves – in addition to poor construction quality and unreliable welds, it was found to have a weight-on-tip percentage of only 13% (this is worse than a CQR). Accordingly it exhibited very poor setting behavior.

The WASI version is available only in 316 stainless. This is a bit of an issue as 316 is not particularly strong – the Rocna is constructed in stainless too, but 2205 high grade duplex steel is used for the shank which has almost three times the tensile strength (and even that is slightly less than our regular galvanized models). Many stainless anchor manufacturers use only 316 for stainless anchors – obtaining in our opinion totally inadequate strengths.

Independent testing

There is a large amount of independent testing of both the Bügel and Rocna. However, the following summary comments from West Marine in the USA relating to their 2006 comparison testing, including the WASI Bügel, best sums up the true differences.

West Marine
2006 testing

Quotes complete
& verbatim

WASI 35 SS (32 lb):
Varied results from 1,300lb to maximum tension. Failure mode was generally dragging.
Rocna 15 (32 lb):
Superb, consistent performance. Held a minimum of 4,500lb and engaged immediately.