Curled tip on a Rocna: What to do?

[30boat]

The anchor didn't break or let go so in my book it didt what it says on the tin.Very hard metal can be brittle and to be fair we don´t know what it was up against.
I don't own a Rocna but would buy one tomorrow if I needed one.

 

[Krusty]

In view of the interest shown, and Grant King's intervention (welcome and appreciated) I will give the fullest information available.
Boat; 32ft, 5 tons. Rocna 15kg, bought from Boyd Boats 2008.
I used twin 25lb CQR's for 40yrs, then a similar weight Manson Supreme for a full season (and very satisfied with its performance as the everyday bower). The heavier Rocna was intended to be for seriously hard weather, but this Spring we set off using it as the bower.
After consulting my anchor-hauling crew, I cannot now be positive as to exactly when the damage was done, or the ground or the weather. I noticed the damage after the anchor was weighed and brought on deck ready for using a 'visitor's mooring' at Castlebay on 16th May.
At crane-out last year I transferred the anchors from boat to car boot and off-loaded them to winter storage. I find it hard to believe that I would not have noticed any such damage then; so it seems to have occurred between crane-in (April) and 16th May. In that time it was laid only six times and not subject to any hard weather.
It is somewhat disturbing to think that the tip could have been distorted without extreme stress.
I would be very interested to learn of any similar experience by other Rocna users.

 

[lw395]

It doesn't seem unlikely that it has simply landed on its point on a solid rock or similar.
I would think any sharp point is going to get damaged if it gets chucked at the seabed often enough. If you have an anchor that works for you in your waters, then I'd go with their warranty.

 

[craigsmith]

You've hung the tip up on something which didn't give first - probably rock - and put a lot of force on it.

One of the design features of the Rocna is its balance, in that all forces are transferred to the tip. That means it'll hang up as well as possible in "impossible" bottoms, like rock, where it can at least have a chance of finding a crack or ledge on which to get a toehold. It also means that the tip can be exposed to damaging forces, when other types have long since let go. Unfortunately steel is steel, and sufficient force will damage it.

It's about a balance between the sharpness of the fluke edge "chisel tip", for setting ability in hard sea-beds; and the durability of that edge. Anchors which make the tip too sharp suffer from this same problem, regularly, and also wear the galvanizing off more quickly, leading to rusting edges. Certain copiers of the Rocna have made their fluke edge sharper still, in an attempt to compensate for inferior performance because of lower tip-weight and other compromises. We have photos of the same damage on the copies, identical except it occurs at lower force levels.

That said, and it's hard to tell from your extreme close-ups which show only the very tip profiles from the side; but it is possible that this anchor had a tip which was too sharp at the very point. The shape from the top is supposed to be rounded smooth to reduce the chances of this. So, get in touch, it'll be sorted for you.

 

[Scotty_Tradewind]

"So, get in touch, it'll be sorted for you".

That's what we like to hear Craig.

And on my second 'long weekend' since ownership, I can report that my baby 10kg Rocna set first time, each and every time and SWMBO slept soundly on it each night.

 

[Krusty]

OK Craig. I'm sure you are right about coming up against rock in 'mixed' ground, probably when powering astern to ensure the set, as we did not have the weather to stress an anchor after setting. It is interesting to note that the curl is upwards, towards the shank, so it cannot have been caused during weighing.
The extreme close-up was necesssary to show the detail of the curl, and to show just how sharp it became during distortion; knife-sharp. When delivered, the point of the tip was as sharp as my Manson Supreme, but not that sharp!
To prevent injury to crew, I intend to simply peine-over the point, rather than file it or cut it, and monitor its condition more closely from here on.

 

[Krusty]

A belated thought:
Is it likely the curled material is not steel, but a blob of excess zinc drained to the tip on removal from the galvanising bath?
That would certainly account for easy distortion, and the tip being sharp-pointed on delivery instead of 'rounded smooth' as you say it should be.
If my thought is correct then the curl can be trimmed flat and I would have no problem (I shall find out when I get a peining-hammer to it). You might have a minor process-control problem.
Fingers crossed!
Once back to the boat, I shall be 'off the net' for a few weeks, so no quick feed-back. Sorry!

 

[dulcibella]

He must be on holiday

 

[doug748]

Too true
Trade it in for a drop forged CQR, I say.