Rusting Spade Anchor

[Ian_Edwards]

I have a spade anchor, bought at the start of the 2014 sailing season.

I've anchored with it well over 500 times since then and it's now very rusty, and I've painted it with Hammerlit special metal primer and white gloss, but that comes off the pointed bit of the fluke more or less the fist time I set it.

I've had the shank re-galvanised, it was done when I got the chain re-galvanised 2 years ago, but the galvaniser wouldn't do the fluke because it is loaded with lead.

I've emailed Blue Water Supplies Limited, and asked them if they have a re-galvanising service, but they don't. They suggested that it might be replaced if I sent it back to Tunisia, with all the original paperwork, which doesn't sound that practical to me.

Has anyone found a reliable UK company who will take the lead out, re-galvanise the fluke and then put the correct amount of lead back in at a reasonable cost?

The boat is currently ashore in the Clyde area.

I'm happy with the performance of the anchor, it's not quite as good as the Rocna I had on my previous boat, but the anchor locker isn't the right size and shape to take a Rocna, the roll bar, would foul the windlass.

It's a real shame that the galvernising is poor on the spade anchor, because otherwise it's a good bit of kit.

I know that post on this forum suggest that it's possible to take the lead out as DIY job. However, I don't have the equipment to handle a 20kg anchor, and get it hot enough to melt the lead out of it.

[GrahamD]

The Spade is an excellent anchor- I know because I fitted one this year. It is also a very expensive and desirable anchor. A bit of surface rust will not adversely affect its efficiency but may make it less attractive to the light fingered brigade if it does not look pristine.

Maybe it is best not to worry about the look of the thing, rather think of it is a badge of honour that shows how adventurous you have been in your sailing. Alternatively, instead of all the cost, faff and effort in trying to get it regalvanised, buy a new one and sell your old one on Ebay to someone who values its properties and doesn't care how it looks. This may be cheaper than regalvanising and would make another sailor happy!

[pcatterall]

What's that process which is 'near to galvanising' that I read about ( or was it a dream?) there was some application like a paint ( but I don't mean a simple paint with loads of 'sacrificial' zinc/lead or similar content but something more sophisticated. I recall ( dreamt?) that if the item was scratched down to base metal then there would still be some 'electronic' (My word !!) bridge providing protection.

[cagey]

Galvafroid is maybe what you’re thinking of.
K

[TonyMS]

Spade sell a rather expensive paint treatment that is alleged to be a substitute for galavising. My problem is that I can't separate the two parts of the anchor because of corrosion in the joint, and I don't trust it not to have structurally significant corrosion there.

[MM5AHO]

Galvanizing: an alloying reaction between steel and zinc where the coating is this alloy and is done by dipping cleaned steel into molten zinc. Typical thickness 80 microns. Bonded metallurically.
Electroplating: a very thin (<10 microns) coating by depositing zinc from a chemical solution electrically. No bonding to the steel.
Sheradizing. A high temperature system of alloying iron and zinc by tumbling steel items in a container of zinc powder. Alloy forms on the surface, and strictly conforms to surface shape. Harder than galvanizing, but usually restricted in size of items coated. Same lifespan per micron of coating.
Zinc rich paints. There are many. Galvafroid mentioned is a good one, as is Zinga (though it claims not to be a paint it is), and many others. This is paint with small zinc particles. Adhesion to the steel can be an issue, like any paint. Protection is better than paint without zinc, but no where near as god as galvanizing or sheradizing.

[noelex]

The steel Spade is a great anchor. The lead ballast significantly helps the performance compared to other anchors using steel ballast and relying on primarly on ballast for the correct orientation. These anchors need a large ballast chamber. Lead is much denser so contributes to a significantly greater righting movement especially in water . However the lead makes subsequent galvanising difficult.

It has been suggested that melting out the lead is easy, but be careful if you go down this route. Large quantities of molten lead can be dangerous.

To alleviate this problem Spade in the USA offer to replace at no charge any anchor where the galvanising has worn. An incredibly generous guarantee, although the transport cost can make this impractical.

Whatever you do, don’t make the mistake of this owner and ignore replacing the lead.

[sarabande]

It would be a much more effective anchor if you removed the lead, regalvanised, then refilled the tip pocket with depleted uranium.


The added advantage of seeing where you anchor lay at night would be most re-assuring.

[westhinder]

It would be a much more effective anchor if you removed the lead, regalvanised, then refilled the tip pocket with depleted uranium.


The added advantage of seeing where you anchor lay at night would be most re-assuring.

Didn’t the great late Eric Tabarly use depleted uranium in the keel of one of his Pen Duicks? And wasn’t he disqualified from his race?

[stephen_h]

Have a look at getting it hot zinc sprayed. This is melted zinc sprayed onto the surface
so shouldn't be a problem with the Lead. Not quite as good as hot dipping but close
and better than painting.