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You Get What You Pay for – or, Fake Bruce Anchors May Be Dangerous

Bruce Anchor
The real thing is shown in the next series of photos. Bruces are forged from a single piece of steel. No welding. Keep in mind that stiffness varies with the cube of the thickness of the item in question, so a little thickness has a huge impact in stiffness. Notice how thick the vertical portion of the shank is in the photo above, and also the thickness of the aft sides of the flukes.
Here is an end-on shot. Again, notice the thickness of the parts of the anchor which have to do the real work when there is a sea running and a gale blowing in your less than perfectly protected anchorage.
Image
Here is where you want the anchor sharp, the leading edge of the main fluke, which has to dig its way into hard bottoms and through weed. The sharper this edge is, the better it will do in hard-to-anchor areas.
Bruce anchor fake
And now a comparison. The flukes are shaped differently – these are much easier to make and we suspect there is a reason for the compound curves of the Bruce (why make them that way, at greater cost, if this does not have a benefit?). More important, look at the thickness of the flukes and stock. These are much thinner than the Bruce. Finally, the intersection of the stock and flukes has a simple seam weld. This is where the anchor will fail, if the shank does not first bend to where the anchor is useless. We would not be comfortable if our security depended on these details.
Bruce anchor fake
This cool-looking, shiny stainless fake Bruce shows clearly the weld of the shank to the flukes. This is the point of maximum load and stress on the anchor, and welds like this are not particularly strong in bending – so, beware. As you probably know, we’ve moved on from Bruce anchors – which were the all-around standard in our opinion for the last 25 years. We now use a ROCNA hook, and have found it to be far superior to anything else we’ve seen. It has a welded shank-to-fluke configuration, but this is done in such a way as to provide added support, so the welds are not fully loaded in bending. If you are using one of the fake Bruces, or thinking about one, make sure the construction details match the original.

Posted by Steve Dashew  (May 17, 2007)




One Response to “You Get What You Pay for – or, Fake Bruce Anchors May Be Dangerous”

  1. Andrew Troup Says:
    Good points, and important info. One minor quibble: the genuine Bruce anchors were cast, not forged. Normally cast anchors are not a good idea in small sizes, but Bruce used steel in lieu of the more usual iron. Cast steel is a completely different animal than iron, and considerably stronger than mild or even medium tensile steel, and their castings were tightly quality controlled, hence their deserved reputation for reliability. (I use the past tense – some reading this might be unaware that, sadly, genuine Bruce anchors are no longer made) Genuine CQRs, on the other hand, had forged high-tensile steel shanks (hammered under massive drop-forging presses when yellow-hot, in toolsteel dies) which were extremely strong and resistant to permanent deformation. I’ve seen photos of them bent sideways well past 90 degrees on test, yet returning to straight when the load is released. If you had to prepare for a hurricane, in a harbour with bottom chains from ship moorings, and lacking any shackles big enough, you could do worse than dive with a genuine CQR and hook it under one. The breaking strength would be higher than for any anchor of comparable weight (The backbone of the plough is also forged, in a genuine CQR)

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