By Alex_Blackwell - 19 Jun 2019
Has anyone exerience with a Knox Anchor?
We are currently taking one out for a cruise. First attempt in hard sand: sets and holds well.
By bbalme - 19 Jun 2019
That's an odd one! What's the split at the front all about? Whereas SPADE has a lead weight right there... Be interesting to see how you fare with it. What weight is it (and what make/size anchor did you take off?)
We're using a SPADE right now - and it's good, though doesn't set nearly as easily as our Manson Supreme. I find that if I try to set it with much less than 5:1 scope, I won't get a good set - whereas the Manson would have dug itself in at 2 or 3:1. The SPADE certainly does fit the bow more easily though!
By Alex_Blackwell - 20 Jun 2019
Yes, this is an interesting anchor and when we found it online, we just had to check it out.
As I am sure you know, anchoring is our subject. We write about it frequently, are authors of the best-selling anchoring book (Happy Hooking) and do regular webinars and seminars on the subject.
In the process of our work we do endeavour to try anything new on the market to stay up to date. So yes, we did remove our Ultra anchor while we gave the Knox a go. In the meanwhile we have amassed quite a collection of anchors...
Interesting your comment on the Spade. To date we have been the only ones who made the same comment. It is an excelelent anchor, but does need a bit more scope to set initially.
By Sandy.Garrity - 13 Oct 2020
I've invested in a Knox, it will be fitted over the winter 2020/21 in the hope that we will be circumnavigating the United Kingdom, COVID allowing in 2021.
If I remember I'll post an update about this time next year.
By Alex_Blackwell - 13 Oct 2020
Do, please keep us posted, Sandy!
By Dick - 13 Oct 2020
What were the attributes of the Knox anchor that lead you to choose it? And not sure what you mean by "fitted"? And I certainly hope, with you, that we are exercising our anchors next season.
Thanks, Dick Stevenson, s/v Alchemy
By DariaBlackwell - 20 Oct 2020
The split in the flukes is intended to release substrate so it doesn't come up with lots of muck like the Rocna does. It does indeed let the mud and sand flow off the anchor much more readily.
By Dick - 20 Oct 2020
That, indeed, would be a nice attribute.
I will be interested in whether split flukes can tolerate the rough and tumble of varied bottom challenges: such as those time when there is differential loading, one side resting on a rock. I would guess that if one fluke was out of alignment with the other, the whole geometry of the anchor would be compromised and the anchor might twist around when setting ina not-so-good way.
Like so many new products, time and multiple usage scenarios will clarify.
My best, Dick Stevenson, s/v Alchemy
By Nimue - 20 Oct 2020
We started our cruse in 2008 with a proper Bruce, that changed to a Spade. The Spade is an excellent anchor and never let us down, although always needed a good clean upon retrieval.
Looking for a spare second Anchor we came accross the Sarca Excel. The company gave us a free trial and we used it in all terrain for a number of months in BC Canada. We found it set very well, even on a short scope and the writing on the anchor blade is good as helps keep it clean.
The spade is now our second anchor, because it splits in two and fits the anchor locker well.
Looking at the Knox I would agree with Dick, the flukes look very vulnerable and I don't think I could trust it in a blow.
By Alex_Blackwell - 20 Oct 2020
Thanks for your comments
We found the Knox worked very well under numerous situations.
Prof Knox designed it based on decades of scientific research. This was published in PBO.
We have posted an article here:
By Sandy.Garrity - 15 Nov 2020
Thanks for your post.
I'll start with what I mean by "fitted", this is some work on the bow roller so that the new anchor fits better. When I bought Aphrodite she came with a poorly fitting Bruce that had clearly damaged the gelcoat in the past, so I wanted a bow roller that will keep the pointy end of the Knox away from the hull and make it easier to deploy. On initial fitting the 13kg Knox just fits in the current bow roller and touches the hull in the same place as the Bruce.
Reasons for choosing the Knox:
1) The Bruce was an ideal anchor for where the original owners located the boat on the east coast of England, my plans are for more varied sailing grounds and I wanted a more modern design with more holding power;
2) I made the assumption that all "new generation" anchors especially ones with roll bars will more or less work the same way;
3) Having the anchor made in the UK and purchased directly from the manufacture this has several advantages. I now have a relationship with the manufacture and can return it directly to them if there is a problem;
4) Knox were very open about what materials and manufacturing processes they used. Nothing fancy in their manufacturing;
5) The design is simple and Knox will regavinise and refurbish the anchor in the future if I ever need that done;
6) The design is a series of triangles and as a retired engineer I like triangles for strength;
7) I liked the half fluke or slot design as I hope this will help self clean the anchor as I raise it. I am not impressed with the "ice axe" pick of some of the new designs;
8) Weight. For the size of vessel I would have needed a 16kg Manson Supreme or a 12kg Rocna Vulcan. The Knox is 13kg.
I will see if I've made the right decision over the next few years.
By Alex_Blackwell - 15 Nov 2020
do please keep us posted on your experience - the advantage of the forum is that you can come back a year later and pick up the thread again.
We very much liked the performance of the Knox anchor. It sets and hold very well.
By Dick - 15 Nov 2020
Thanks for the fill.
And yes, good as these new gen anchors are, many boats need to adjust their bow rollers and sometimes over-all anchor handling procedures, to accommodate. It is worth it, however.
And it is also a chance to re-think anchor handling gear, especially bow rollers which are too often designed far too lightweight and bring the anchor up to ding the topsides.
A couple of general comments, not necessarily for you, but for other readers who might come across this thread.
I am not sure that the Bruce anchor was ever an ideal anchor for any conditions in the kind of weight that a recreational vessel carries. The east coast of England has, generally, such a lovely seabed for holding an anchor as one could anchor with a safety pin and fish line.
That comment aside, with the advent of the new generation anchors, I would suggest that any skipper wanting more than a lunch hook, would be practicing good seamanship by turning their old gen anchors, their Bruce, CQR etc. into lawn ornaments.
I suspect you are correct that “all "new generation" anchors especially ones with roll bars will more or less work the same way”. That said, I remember when Danforth anchors started being copied, and sold for far less money, tests showed that even a few degrees difference (stock to fluke) made significant difference in ground tackle effectiveness: setting and holding: in other words, Danforth had it right.
Please be aware that there are accumulating reports (occasional, but not rare) of roll-bar anchors not resetting after a wind shift (or current change). The best documentation for this is with the Rocna anchor, but reports seem to suggest that the roll bar contributes to this occurrence among other possible contributions. Jury is still out.
Agree that “Made in the UK” makes for confidence. And I do like “nothing fancy in their manufacturing”.
It is nice to think that you can give the anchor back to the manufacturer for re-galvanizing, but that is so seldom a process that, while nice, it would not play much in my decision of what anchor to buy. And not sure what is meant by refurbishing. If, for example, what is meant is that a fluke got a little out of alignment with its partner (an earlier concern I wrote about) then I would suggest that bending it back into alignment would be unwise and end up with a weak fluke likely to bend again: better a new anchor.
Chain and anchors do not really self-clean, especially in mud. That said, the new gen anchors can come up with a huge scoop of seabed which is a pain to get rid of. For many/most thick mud conditions, I would suspect the slot will make little difference in the collection of seabed and what it comes up with (after all, that is what holds you to the bottom) but it may facilitate the seabed getting sprayed off the anchor by a deck wash by giving an exit point in the slot.
Which brings me to another related topic: the importance of a pressure deck wash. This is almost essential for the new gen anchors as they come up with so much seabed/mud. Getting the anchor and chain clean is an important maintenance chore. You mentioned re-galvanizing. Those who store anchor and chain covered in mud are shortening the life of their ground tackle impressively. Not only does mud hold moisture next to the metal for long periods, but this mud is a mix of the seabed, which in many areas holds an impressive concoction of un-natural elements that can eat away at things.
This goes double for chain if brought into the anchor-well muddy, left to percolate with little air movement, no sun or rain and does not enjoy the cleansing rain that the anchor might enjoy. Even worse might be the seaweed or other organics brought in with the chain and contributing also to boat smell). If good quality chain is sprayed completely clean on its way into the anchor well, given a fresh water rinse when possible at a dock, and turned end for end every few years, it will last for a very long time.
A good strong deck wash is a wonderful piece of kit and I think essential for the new gen anchors and makes storing clean chain much much easier.
I am thinking when you say you ”would have needed” the various size anchors you mentioned that you are taking this from one or more of the anchor weight suggestion guides that are in books and magazines and manufacturer’s suggestions. I do not know the size or type of boat you sail, but in general, I find that the guides underestimate the bower’s weight by at least one size and generally two. You report setting out for more varied cruising grounds which sounds great. But it is likely that these more varied grounds will generate more varied weather/wind conditions where a good anchor, well set will allow for a good nights sleep.
And, as Alex requests, please give us field reports.
And, thanks for the opportunity to kick off your report for general and related topics.
Come back with questions/thought etc.
My best, Dick Stevenson, s/v Alchemy