Installing a zinc anode on the anchor

[Rigdaddy]

Originally Posted by SouthernPride

Can't you re-galvanize the anchor by spraying a zinc coating on it. Lowes and home depot sell the exact same Zinc spray that you pay 4 times the price for from a marine supplier.

Spray on zinc paint is not nearly as effective as hot dipped galvanizing.

[Rigdaddy]

Originally Posted by Pauls

Attaching a zinc anode to a galvanized anchor won't help protect the galvanizing much because both are the same metal. But if you attached a chunk of magnesium, which is significantly lower on the scale than zinc, that would protect the galvanizing. I think its a good idea.

For an anchor that has lost its galvanizing then attaching a zinc is an excellent idea. Make sure that your attachment method has very good electrical conductivity or it will be ineffective. By far the best way to attach zincs to a steel part is to use a zinc made for steel boats with a cast in steel bar. Bolt the bar on, but also make a small tack weld from the bar to the anchor. This guarantees a perfect electrical connection which will not degrade over time.

Well put.

[bigman1]

Originally Posted by GTom

Mine doesn't have a drop of the coating left. Regalvanization would cost the same as a new anchor.

Put your rusty metal in white vinegar (very cheap) leave it soaking for 2 days
hose it down,no rust,then paint it with Zinga cold galvanizing or similar,Zinga claim 99%pure zinc.I have no connection with them!

[GTom]

Originally Posted by bigman1

Put your rusty metal in white vinegar (very cheap) leave it soaking for 2 days
hose it down,no rust,then paint it with Zinga cold galvanizing or similar,Zinga claim 99%pure zinc.I have no connection with them!

Thanks for the hint, I'll do that!

[SV Bacchus]

I have a stainless swivel between the anchor and the chain. I spent a little time this past week and cut off 1.5 meters of chain because the 1st meter was rusted so bad and had lost about 40% of its original size.

I just took it for granted this was something I would end up doing when needed until replacement of the entire chain (possibly in 2 or 3 years).

After reading this I'm going to try finding a zinc I can bolt to the chain a link or two above the anchor! As Jimmy Buffett sang in one of his songs "It was so simple it plumb evaded me."

Thanks for the tip forum members, I'll let you know in 6 months how it is working out!

[SV Bacchus]

After reading my post I realized I may just transfer the problem from the chain to the anchor so I guess I will find a zinc for the anchor as well. Can't be careful enough..

[Mike Banks]

Since the anchor is galvanised already and so is the chain--one would gain little.

If the galvanising on the anchor is being eroded--the culprit is possibly the negative connection to the anchor windlass battery, which forms a nice leakage path to the sea bottom via windlass chassis--and also chain and anchor to a good earth--the salty sea..

This is usually a permanent connection, the positive being connected via the foot switch.

I always disconnect the negative to the windlass also once the anchor is set or raised. A switchable 100 amp overload circuit-breaker does it for me. That stops all leakage to earth via the anchor and chain whether deployed or just parked in a wet locker.

[Oceanride007]

I just bought a new anchor, cost a boat buck.
Bottom end of my chain is rusty not overly so, feel that the thin galvanised coating on Anchor, will be sacrificed to protect chain, that would be a waist.

Now i know that the electrical connection across chain links is not great, my stock is Hi-Tensile have to be cautious, think I will put something on the chain a couple of links from the Shackle, that will give me some time.

I don't believe a anode on the fluke will protect a anchor if the anchor is buried, which it will be most of the time, will look into magnesium as protecting zinc is the issue, need something that would not get caught up at bow roller. My random thoughts here, no solution yet.

[Frugal]

After re galvanising my anchors a couple of years ago I attached two zinc anodes to the back of the flukes on my main anchor. The thought being to double the amount of zinc available and so double the life of the anchor.
After two years of fairly constant use I note that the added anodes are around 70% and the anchor galvanising is in excellent shape. An added advantage is the extra weight to help set the anchor. Go for it.
Cheers.

[peter57]

Originally Posted by SV Bacchus

I have a stainless swivel between the anchor and the chain. I spent a little time this past week and cut off 1.5 meters of chain because the 1st meter was rusted so bad and had lost about 40% of its original size.

I just took it for granted this was something I would end up doing when needed until replacement of the entire chain (possibly in 2 or 3 years).

After reading this I'm going to try finding a zinc I can bolt to the chain a link or two above the anchor! As Jimmy Buffett sang in one of his songs "It was so simple it plumb evaded me."

Thanks for the tip forum members, I'll let you know in 6 months how it is working out!

Hi Bacchus,

Get rid of the stainless swivel, if you want to use a swivel use a galvanised one.

On my boat the PO has put an expensive stainless swivel on which has eaten all the gal off a 4 year old Mason supreme (a terrible anchor as is does not like to reset) I have purchased a Spade anchor which I am contemplating on, if to paint it with epoxy zinc even before it goes on to the boat, as there are many in our yard that epoxy zinc coat their anchors every time they haul out.

[SV Bacchus]

Originally Posted by peter57

Hi Bacchus,

Get rid of the stainless swivel, if you want to use a swivel use a galvanised one.

Yeah, that is a good thought as well. I'm a little leary of the stainless swivel anyway, the PO had put it on and I can't even find a brand name on it!

If I switch over then I may not have to worry about zincs on the ground tackle.

[Alan Mighty]

Originally Posted by Oceanride007

I don't believe a anode on the fluke will protect a anchor if the anchor is buried, which it will be most of the time, will look into magnesium as protecting zinc is the issue, need something that would not get caught up at bow roller. My random thoughts here, no solution yet.

Unless you're anchoring in freshwater, magnesium is not going to do much for you.

Zinc on your anchor, whether as a thin galvanising layer, a chunk as a sacrificial anode, or a zinc-rich 'dry galvanising' paint, will work whether the anchor is embedded in the substrate or suspended in the water column.

And even in the air, when your anchor is on deck. That's why roofing iron is galvanised, nicht wahr?

All the substrates in which you embed your anchor are wet, no? And with chloride ions in that water too.

Do you carry your anchor up the beach and embed it by hand above high tide level? It's relatively dry there (except when it rains), but you'll find salts with chloride ions in amongst the sand grains.

[Lepke]

When we had light ships that anchored for long periods, several zincs were on their anchors.

[RaymondR]

I spray my chain with boiled linseed oil. Seems to inhibit rust on the chain where the gal has worn off and lubricates the chain when it passes over the wildcat and also prevent rust stains on the for deck.

[peter57]

Originally Posted by RaymondR

I spray my chain with boiled linseed oil. Seems to inhibit rust on the chain where the gal has worn off and lubricates the chain when it passes over the wildcat and also prevent rust stains on the for deck.

Thank you Raymond, well brought to the discussion, old trick with Gal rigging as well.