Galvanizing -- how far to go

[sailingharry]

My boat came to me with 300' of galvanized 5/16 G4. I am pretty sure it is original to the 1998 build, and it clearly needs regalvanizing. A local shop (Baltimore, MD, USA) can do it for around $1/lb. That part is easy. I'll be doing it later this winter.

I also have two anchors.

My bower is a 25kg Rocna. It's much newer than the chain, and mostly in good condition, but I have covered 8000 NM mostly anchoring in varied conditions. The tip and a bit of the edges is rusty, but if not for the opportunity to throw it in with the chain, I'd ignore it.

My secondary is a 30kg Claw (Bruce clone). It is a very dark gray color, not typical galvanizing silver. There is no rust. I have no idea its age, and have never used it on the boat (but it did serve as a tie-off at my dock for close to a year).

For around $60 each, I can get them regalvanized. Is there any downside to doing this, and is there really a significant benefit for the cost?

Thoughts?

[JPA Cate]

No downside, imo, but I'm not sure what the brown stuff on the claw is. If it even might be rust, then I would do both. Then, you'll be set for a few years. It will be getting more difficult to locate galvanizing services, because of the toxicities involved--and also more expensive, based on the trends here in Oz.

Normally, the original galvinizing you get on new anchors is pretty thin, and usually, the re-galv will last years longer than the original.

Good luck with it.

Ann

[MicHughV]

Re: the anchors....other than some rust being unsightly, is there any noticeable wear and tear on the anchors?
If not, hardly worth the effort.
You can also buy some spray on zinc paint to give the anchors a touch up. Might cost $5. The paint last surprisingly long, and a quick re-coat is just a trip to the hardware store.

Judging from the attached photo's, I don't see much rust on the anchors to be concerned with.

Re: the chain. You could try reversing the chain. It's unlikely that all the chain is rusted. 300' is a lot of chain.
You could also just cut off any rusted chain, and go with a nylon/chain combo.

Can't speak for you others, but have managed fine for over 35 years with just 75' chain, followed by nylon rode on each anchor.

Just some points for consideration.

[Pete7]

I would have the chain galvanised because as Ann says its getting difficult to have chain done. One really good firm in the UK who made my chain has given up on galvanising and moved out of the marine market for small chains only doing large commercial stuff now. Most leisure chain in the UK is now imported and boy has the price gone up lately. Now £6 - £8 a metre.

If you have never used the Claw, then ditch it because its a copy and use the cash to buy a second hand Fortress. That saves you 30kgs and much easier to deploy if you have to. Dragging a 30kg anchor out of some locker quickly isn't going to be easy. We sold our Claw and replaced it with a Danforth because Fortresses are really expensive in the UK.

Pete

[MicHughV]

I've had chain re-galvanized. It's a PITA. The galvanizing plant is typically far out of town, if there is even one, otherwise throw in a long journey to somewhere.

The galvanizing process leaves the chain with a number of spiky ends on individual links as it gets pulled out of the zinc vat. You find you'll need thick gloves to handle the chain.

When I came to pick up my chain, it was clear that the chain had been dropped willy-nilly into the zinc vat, as many links were fused together.

All in all, I wasn't overly happy with the process.

An option to consider. In my neck of the woods is an marine supplier establishment that caters to the large ships. The price of their chain is easily 1/3 or less of your regular marine hardware store. They typically carry every size and type of link.
I would search one of these places out. Most any town/port that caters to ships will have such a place.

I ended up buying new chain there.

[SailingHarmonie]

Originally Posted by sailingharry

My boat came to me with 300' of galvanized 5/16 G4. I am pretty sure it is original to the 1998 build, and it clearly needs regalvanizing. A local shop (Baltimore, MD, USA) can do it for around $1/lb. That part is easy. I'll be doing it later this winter.

I also have two anchors.

My bower is a 25kg Rocna. It's much newer than the chain, and mostly in good condition, but I have covered 8000 NM mostly anchoring in varied conditions. The tip and a bit of the edges is rusty, but if not for the opportunity to throw it in with the chain, I'd ignore it.

My secondary is a 30kg Claw (Bruce clone). It is a very dark gray color, not typical galvanizing silver. There is no rust. I have no idea its age, and have never used it on the boat (but it did serve as a tie-off at my dock for close to a year).

For around $60 each, I can get them regalvanized. Is there any downside to doing this, and is there really a significant benefit for the cost?

Thoughts?

We had our chain regalvanized while we were in Annapolis a couple years ago. It was easy, painless, and about 25% of the cost of new chain, and the galvanizing was WAY better than most new chain comes with.

The story of our experience is here:

https://fetchinketch.net/2021/10/27/...for-a-project/

Our 100 meters of 10mm HT chain did not rise to the minimum price for a job, so we threw in the anchor as well, essentially for free. Again, the new galvanizing was thicker and heavier than the original. Not as “pretty” but its an anchor, not a piece of art. Assuming the galvanizing is done well, there is no downside to regalvanizing an anchor before it “needs” it.

[grantmc]

Re-galvanising chain doesn't make it new chain. It will still be old with links here and there stretched, scraped and bent. All that galv or paint does is make it look nice, weigh more, and give a false sense of security. That's like saying a new coat of paint is an engine rebuild. My 2 bobs worth.

[Jammer]

Originally Posted by sailingharry

My boat came to me with 300' of galvanized 5/16 G4. I am pretty sure it is original to the 1998 build, and it clearly needs regalvanizing. A local shop (Baltimore, MD, USA) can do it for around $1/lb. That part is easy. I'll be doing it later this winter.

..nod.. You'll be paying $300 for galvanizing. New chain would be around $900, maybe less in your area where you can probably find places that are local that stock it, so you would not have to pay freight. If it is not really worn but is showing rust, I believe what you are doing makes sense -- especially if there's low hassle involved in your situation. The logistics of getting 300 pounds of chain to and from a local shop are not necessarily straightforward.

My bower is a 25kg Rocna. It's much newer than the chain, and mostly in good condition, but I have covered 8000 NM mostly anchoring in varied conditions. The tip and a bit of the edges is rusty

The Rocna is made of heat-treated steel and might (maybe) lose some of its strength during the galvanizing process, which is performed at around 830° F.

Surface rust at the tip and edges are not problematic as long as the bulk of the galvanizing is intact. Galvanizing protects adjoining areas just as a zinc protects adjoining steel propshafts etc. I am not sure that regalvanizing the Rocna solves any problem that you actually have.

My secondary is a 30kg Claw (Bruce clone). It is a very dark gray color, not typical galvanizing silver. There is no rust. I have no idea its age, and have never used it on the boat (but it did serve as a tie-off at my dock for close to a year).

Pete7 speaks my mind. Sell it and get something better.

For a secondary, look at the Sarca Excel Aluminum or the Spade Aluminum. These anchors disassemble for storage and are light for their holding ability, and are ideal as a secondary if cost is no object. The light weight makes them easier to handle in a hard chance, and they perform well enough to serve as a replacement for your Rocna for months should you lose it.

The Fortress that Pete7 mentions is another good choice. You're probably aware of the tradeoffs; the Fortress is lighter, cheaper, and easier to store but will not reset as reliably on a wind shift. My boat came with a Danforth HT secondary which I have kept, though it would not be my first choice. Ironically, it's a better anchor than the undersized generic anchor that was on the bow when I bought the boat (and which I have since scrapped).

In any case, the Bruce clone is bulky, heavy, and of doubtful effectiveness. The clones vary in their performance but none is the equal of the original.

[Tin Tin]

As the chain ages stretches and rust develops, it gets thinner in spots and starts slipping in the gypsy and shedding rust particles on the deck.. If you have no slippage (usually determined by hockles forming in the chain locker) then your chain may be worthy of regalvanizing. Chain from 1998 that still works might have been regalvanized at some point, or used in fresh water, or hardly used at all. As for your Rocna, it will last for years more, but if it irks you get it re-galvanized, it won't hurt other than the hip pocket.- (probably outlast you or the boat). We had our Rocna regalvanized in year 8 made it look pretty again. As for the Claw I would cash it in for scrap and get an alloy Fortress.

[grantmc]

Thought the following from the Rocna web site might assist:


WHAT IS THE PROCESS OF RE-GALVANIZING THE ANCHOR?
Rocna uses a high-tensile steel in the shank, and this requires a bit of extra attention during the re-galvanizing process to ensure that the “pickling solution” used to clean the anchor before galvanizing does not damage the steel.

The recommended procedure is as follows:

1. Remove all labels, glue reside under labels, and stickers from the anchor.

2. Sandblast to remove all old galvanizing down to bare steel (surface needs to be clean of all old zinc).

3. Let the galvanizer know that there is high tensile steel in the shank, and that they need to “Flash Pickle” the anchor before galvanizing, and not to use an extended soak in the pickling solution.

4. Hang the anchor tip-down for dipping in Zinc.

5.Re-galvanize to a Zinc thickness between 100-200 microns.

6.Clean up any sharp edges or spikes with a hand file, making sure not to remove too much zinc and expose bare metal

7.If there are any small pinholes in the galvanizing which go all the way down to bare steel cover them with a good quality cold-galvanizing spray. The galvanizers should be able to recommend or supply this.

8. Apply new Rocna labels. (We can supply).

[MicHughV]

When I had my chain re-galvanized, it was apparently lumped in with a variety of other items.......boat trailers, other chain, etc, such as that I could visible see from my visit there.
Quality control was pretty much non-existent as far as I could tell.

My chain represented probably 0.005% of their monthly product, so I could understand little effort was made to clean it, prepare it and so on.

In addition, the plant was a good 50 miles from my location, so a 100 mile round trip, and come back in 3 weeks time to pick it up, another 100 mile round trip, which is likely representative of most places.

A ship's chandelry, was for me, the far better option, as I got brand new chain at a discounted price, having managed to sell my re-galvanized chain and if this option exists for anyone is worthy of consideration.

[Kettlewell]

I've never had anything regalvanized. Never had an anchor get so rusty that I needed to retire it, and with chain by the time it gets to the point of regalvanizing it tends to have a few bad links here and there that mean I want to cut it up anyway. I can often get several 50-foot or greater lengths that are still good out of the old chain, and those are great for backup anchors, secondary anchors, temporary moorings, etc. I've also given away a bunch of still usable chain that was pretty rusty because I look at it as part of my insurance plan. During the next hurricane I don't want to be wondering if my insurance has a bad link somewhere I didn't notice.

[MicHughV]

Just seeing rust on an anchor chain is off itself not a concern. Steel can throw off a tremendous amount of rust, and some visible surface rust probably does not affect the strength of the chain in any discernable manner.
Most all chain manufacturers use a 5:1 safety factor when determining a safe load criteria for chain.
I have been involved in several studies to investigate rust on steel in a marine environment during my career as a marine engineer and rust on steel is a well documented subject.
You'd need to inspect the chain link by link to really see if any rust is more than surface rust which could be cause for concern.

[David Mathis]

Pete7 seems to dislike the Bruce but we've used a 20k for many years. The only issue was the rounded leading edge which was sharpened with an angle grinder after a dragging incident on hard packed sand. The top galvanizing was also smoothed to aid penetration (like aircraft lift/drag ratios) then the exposed areas were painted with cold galvanized and the polished area was sprayed with graphite paint, available at Tractor Supply. Although a Danforth is about the best for a straight pull in sand, the Bruce shines when the direction of pull changes. We've been in a few storms that buried the anchor so deep that a major effort was needed to retrieve it the next day - but it held.

[MicHughV]

I'm with you on the Bruce...it has been my anchor of choice for over 35 years. Never, ever had a problem with it. However, the "Claw" is a Bruce knockoff, I think it looks much like the Bruce, but maybe it isn't ??