wearing out anchor

[sailorboy1]

Maybe it is just me, but the thought of just replacing an anchor that has served me well during full time use just doesn't seem a big deal.

[deblen]

Suggest putting a SS sleeve (tube) on the anchor shackle pin & drill the anchor shank just large enough for the sleeve to pass through it.
The idea is to have the sleeve rotate on the pin rather than in the anchor.
Personally,I would use a bolt & nut with cotter/split pin type shackle pin,with locking wire thru the cotter hole,but whatever.
Cheers/Len

[hpeer]

Sean.

Have 2 steel boats I get to look at dissimilar metal corrosion too frequently. There is a metal boat maintenance book and the author goes through the theory. But then provides examples of corrosion that just does not obviously fit the model. One personal example, kind of the opposite of your issue, my CQR rotted out the mild steel bow sprit where they laid close together, but without touching.

My guy tells me that you are the right track. Introduce something that will donate electrons faster than either the anchor or the chain or shackle. A small zinc bolted to the anchor would work. You obviously want something that won’t foul your gear. This should be pretty cheap and you could monitor to see if it is working. I would not drill into the shank. My understanding is a zinc provides protection in a decreasing amount from the zinc out to about 40 feet. You should he able to mount the zinc anywhere in the anchor it is unobtrusive and still get the protective benefit.



You could also try painting hour anchor with a high zinc content primer, but that would be expensive and hard to get. Next would he to paint the anchor with a high ALUMINUM content primer like Pettit RustLock. The el cheapo but might work solution would be to spray the anchor with cold galvanizing paint, high zinc content.

You would have to recoat periodically as the zinc or aluminum gets eaten away.

Good luck.

[Don C L]

I have never heard of this. But then I haven't seen everything yet. This suggests to me the quality of the metal and/or galvanizing of the anchor is suspect. But you said it was very rusty with big flakes coming off? And after 6-7 years it looked sketchy and you kept it for 10 years? A cheap Bruce knock-off? Any anchor that is badly rusted, and rusting, will fall apart eventually. I am kinda surprised it lasted 10 years holding the boat in storms.

[seandepagnier]

Originally Posted by sailorboy1

you waited that long on a boat critical item

My anchor is 12 years old and the last 5.5 years I have been full time on it. I don't see any wear at the shackle location.

I did not really notice it until 6 or 7 years.. but it really depends where you anchor I think more than just how many years.

Originally Posted by PippaB

How about a sleeve made of Monel tubing? That's how my chainplates were built 20+ years ago. The stuff is expensive, but you need, what, 1/2"-1" (1-2cm)? The difficulty would be finding the right OD to match the hole in the shank. McMaster has 1/2" OD, a foot length is $30-40. Make up a dozen bushings/sleeves and change them out every couple of years - last you a lifetime.

I dont think monel or anything metal is a good idea as it will eat away at the anchor which is only steel.

Originally Posted by Muaddib1116

Sounds terrible. I probably would have moved somewhere more protected.

I moved... all over the world. Not everyplace is always protected all the time. It is not always possible to find better protection.

The reason is that it makes it hard/impossible to get the shackle bow through the slot. Most people prefer to have the shackle bow through the shank slot rather than the shackle pin. That being said, check out the Sarca Excel, they have extra material at the shank slot. I had to use a bolt and steel plate to spread the bow of my Crosby shackle apart to get it wide enough to fit.

it wore toward the end, elongating the slot. I don't think it would be an issue to add half an inch or so more metal, but I dont see this i any anchors.

Originally Posted by JebLostInSpace

I'm still not convinced you're getting my pvc concept, but I'll drop it since it has the bending issue I'm not sure how to solve.

Again, the metal would just crush the pvc or any other plastic. Now.. maybe some super plastics would work for a while, until a serious blow and then they would probably get crushed too.

Originally Posted by Don C L

I have never heard of this. But then I haven't seen everything yet. This suggests to me the quality of the metal and/or galvanizing of the anchor is suspect. But you said it was very rusty with big flakes coming off? And after 6-7 years it looked sketchy and you kept it for 10 years? A cheap Bruce knock-off? Any anchor that is badly rusted, and rusting, will fall apart eventually. I am kinda surprised it lasted 10 years holding the boat in storms.

Yes, the metal itself is know to be mild steel I believe which is not hardened like better anchors. Yes, I used 3/8 chain until the links had 3/16" left in them an many other things. Considering it is a solid piece of metal, the design itself tends to last as there is more metal than needed for strength..

I guess the best option is somehow put a zinc there which will also protect the anchor and chain a bit too and has far more compression strength than any plastic.

[Muaddib1116]

Originally Posted by seandepagnier

it wore toward the end, elongating the slot. I don't think it would be an issue to add half an inch or so more metal, but I dont see this i any anchors.

If the distance between the aft end of the shackle slot and the aft end of the shank is too large, it will bind the shackle, which could cause the anchor to perform poorly. I'm guessing anchor manufacturers would rather put out an anchor that doesn't bind on shackles and risk having their customers buy a replacement on some frequency then putting out anchors that bind and perform poorly and don't end up selling well.

[seandepagnier]

Originally Posted by Muaddib1116

If the distance between the aft end of the shackle slot and the aft end of the shank is too large, it will bind the shackle, which could cause the anchor to perform poorly. I'm guessing anchor manufacturers would rather put out an anchor that doesn't bind on shackles and risk having their customers buy a replacement on some frequency then putting out anchors that bind and perform poorly and don't end up selling well.

Yes but they could put a lot more metal than they do and still not have it bind.

[donradcliffe]

I did have a similar issue with the towing eye in an aluminum dinghy. I ended up putting a short piece of reinforced vinyl hose on the shackle pin. Although the loads on the dinghy painter are lower, the aluminum eye has much lower chafe resistance than a steel anchor.
It would last several years between replacements.

[Jim Cate]

Sean, I think that you are chasing a false worry. I've been enmeshed in the cruising community for around 35 years now, and I've lived primarily at anchor during all those years... and you are the first person that I've encountered who has had such a wear issue. I can but think that there was some extraordinary factor involved in your case, most likely a flaw in the metal from which the anchor was fabricated... something that none of the rest of us have encountered with all the varieties of hooks that we've used.

The only wear issue I've heard of is the hinge pin in CQR anchors, and they indeed do wear, and that wear does affect its performance... but that's quite different from your experience. In your situation I'd just obtain a different anchor and equip it normally with a shackle... and then watch it for a while. I'll bet you can't measure any wear for a very long time.

Or you can obsess about this non-problem and entertain all sorts of mickey mouse 'fixes' while your cruising life ticks away, never to return. Your choice.

Jim

[Simi 60]

6 years of full time anchoring with 60 tonne sawing at it.
Zero wear on anchor

I guess in the next 12 mths it's all going to turn to custard

[seandepagnier]

I imagine it is because of the knock-off bruce are built using inferior steel compared to most anchors, and I put it through a lot more than most users. This was a $60 anchor (with free shipping) when I got it.

So perhaps a better quality anchor would last much much longer. How much I have no idea, perhaps 6-10 times longer. Perhaps a hardened shackle on a soft anchor is really bad. I recall reversing the chain then discarding it twice during this time, wearing the links out until they were < 1/2 the original size at the ends of each link.

Saying this is not a problem to me is like saying an anchor doesn't need a zinc. Clearly anchors do wear out the galvanizing as do chains, and would benefit from having zincs, but still few people bother with zinc on ground tackle. It would make sense to me to use a zinc here for both wear and corrosion resistance, but need to cast a specialized shape zinc to make it work.

[rslifkin]

Originally Posted by seandepagnier

I imagine it is because of the knock-off bruce are built using inferior steel compared to most anchors, and I put it through a lot more than most users. This was a $60 anchor (with free shipping) when I got it.

So perhaps a better quality anchor would last much much longer. How much I have no idea, perhaps 6-10 times longer. Perhaps a hardened shackle on a soft anchor is really bad. I recall reversing the chain then discarding it twice during this time, wearing the links out until they were < 1/2 the original size at the ends of each link.

Saying this is not a problem to me is like saying an anchor doesn't need a zinc. Clearly anchors do wear out the galvanizing as do chains, and would benefit from having zincs, but still few people bother with zinc on ground tackle. It would make sense to me to use a zinc here for both wear and corrosion resistance, but need to cast a specialized shape zinc to make it work.

It's quite likely that a better quality anchor would take much longer to show the same issue. Quite possibly long enough that you'd either damage or lose the anchor first. Or have replaced it for other reasons.

[Muaddib1116]

So 60 to 100 years? What is a reasonable life for a heavily used anchor?

[seandepagnier]

I can say I dove to 50ft twice to retrieve it from getting jammed between rocks, as well as a dozen or so times in the 20-30ft depth a few times in zero visibility cutting my arms on barnacles feeling the chain to untangle it from the mess of anchors it was stuck on.

Some other cruisers I met got their anchor stuck in the same spot in charleston (had warned me before I anchored there) and they just cut the chain and bought a new anchor, and did not even attempt to dive for it. I knew I could get mine back no matter what it got stuck on and always did.

[rslifkin]

Originally Posted by seandepagnier

I can say I dove to 50ft twice to retrieve it from getting jammed between rocks, as well as a dozen or so times in the 20-30ft depth a few times in zero visibility cutting my arms on barnacles feeling the chain to untangle it from the mess of anchors it was stuck on.

Some other cruisers I met got their anchor stuck in the same spot in charleston (had warned me before I anchored there) and they just cut the chain and bought a new anchor, and did not even attempt to dive for it. I knew I could get mine back no matter what it got stuck on and always did.

Some may lack the skills or tools to recover one manually from that depth. Even more so in colder water.

I'd absolutely agree that if you can recover it, do it. If not, I'd consider buoying it to come back with more skills or tools to give it a try.