Niander
Well-Known Member
Hi is it worth getting the anchor chain re galvanised
or is it just too expensive?
also anywhere in Glasgow that can do it ?
or is it just too expensive?
also anywhere in Glasgow that can do it ?
chain re galvanised? Glasgow?
- Thread starter Niander
- Start date
doug748
Well-Known Member
I have found it well worth doing particularly if you have trusted, perhaps calibrated chain that suits your set up. It might cost 60 or 70 quid for a good, thick hot dipped coating but it will normallly far outlast new chain.
You appear to be well served in Glasgow, see here:
http://www.galvanizing.org.uk/index.php?cms_id=361§ionTitle=Scotland
If there is a minimum charge/weight you can make it up with other items (anchor/kedge/etc). The usual process for chain involves a "spinner" to remove excess zinc so look for a company that offers that service. Painted items cannot be treated so if you have the odd painted links carfully remove it with stripper. Any chain which is fully painted is normally scrap.
You appear to be well served in Glasgow, see here:
http://www.galvanizing.org.uk/index.php?cms_id=361§ionTitle=Scotland
If there is a minimum charge/weight you can make it up with other items (anchor/kedge/etc). The usual process for chain involves a "spinner" to remove excess zinc so look for a company that offers that service. Painted items cannot be treated so if you have the odd painted links carfully remove it with stripper. Any chain which is fully painted is normally scrap.
D
Deleted member 36384
Guest
Would you elaborate on why a fully painted chain could be considered as scrap please?
awol
Well-Known Member
Highland Colour Coaters in Cumbernauld have done 2 chains for me. Needed a clout on every link to make sure it was free and gloves until the wee spikes of zinc wore off (took a couple of outs and ins). They have a minimum charge which is on the weight added of zinc so find a friend or 2 who want their chains done as well and add a shackle or something to tell them apart. 50m x 8mm chain + 25lb CQR was a lot less than the minimum.
doug748
Well-Known Member
In the sense that the bloke will say:
"More than my jobs worth to touch it mate, bin it any buy some new stuff"
vyv_cox
Well-Known Member
I researched the subject and wrote an article for YM about two years ago. Roughly speaking the cost of re-galvanising is a quarter of the cost of new chain. My regalvanised 8 mm chain is still in excellent condition, which is far more than can be said for the original galvanising that was failing after one season. Painted chain will cost more as it passes through the zinc twice, first time to burn it off. In the case of B.E.Wedge, who did mine, there is no minimum weight but you will need to wait until they have sufficient orders to justify starting the line, usually up to two weeks.
ffiill
Well-Known Member
Understood that to get dipping to work chain had to be clean/rust free.
I do know that here in Inverness there are several firms who send off stuff to be dipped down Aberdeen way-they were quite prepared for cash to send my bits with their big orders.
Chain has to be fettled afterwards as it can get spiky and possible problems with windlass Gipsy if its calibrated.
On other hand there is firm down on Clydebank(Yoker) that does very good deals on new chains;anchors etc.Forget their name but list in Yell as mooring specialists. Recall going into town down Great Western Road you turn of to right just past BandQ superstore.
I do know that here in Inverness there are several firms who send off stuff to be dipped down Aberdeen way-they were quite prepared for cash to send my bits with their big orders.
Chain has to be fettled afterwards as it can get spiky and possible problems with windlass Gipsy if its calibrated.
On other hand there is firm down on Clydebank(Yoker) that does very good deals on new chains;anchors etc.Forget their name but list in Yell as mooring specialists. Recall going into town down Great Western Road you turn of to right just past BandQ superstore.
vyv_cox
Well-Known Member
No, the process removes rust and existing zinc by pickling in hydrochloric acid and paint by burning it off in the molten zinc as a separate, initial process stage, hence the additional cost. My chain had no paint on it but it was surface rusted throughout. No problem nor additional charge for that.
MM5AHO
Well-Known Member
Think I can answer this one, being a galvanizer...
Rust is not a problem to a galvanizer (unless so thick that the integrity of the chain is in doubt). As Vyv said, the cleaning process (dilute hydrochloric acid) removes rust, and also residual zinc from the previous galvanizing.
Most galvanizers have a minimum order charge - they're used to dealing with customers who have truckloads of stuff, many tonnes at a time. (About 500-600 tonnes of steel a week is galvanized between the five galvanizing plants in Scotland). Those plants are in Elgin, Cumbernauld, Forfar, and two in Glasgow. (see link from the trade association website someone has posted)
Chain can be done in a plant that has a spinner (centrifuge) plant (there's only one in Scotland, it's in Elgin), or can be vigorously agitated as it comes out of the zinc, throwing the surplus zinc off before it solidifies.
There are two main layers to a galvanized coating, the alloy layer - thinnest and next the steel, and the zinc layer, on top. Zinc is softer than steel, alloy is harder than mild steel. Both are equally good at corrosion protection.
The minimum charge amount varies between companies, from £60 to £100. Typical rate for the galvanizing other than the minimum charge is £0.50/kg of steel. (In order to confuse the price, a base price plus various surcharges are quoted, but you really only are interested in the total price, not what those pricing mechanisms are)
It is NOT priced on the zinc weight added (as mentioned above), but on the finished weight of the whole item.
8mm chain weighs about 1.4kg/m, so a 50m chain might weigh about 70kg, and cost about £35 for the galvanizing. But you'd pay the minimum order charge. So doubling up the order with a mate, or doing two chains would make this better value.
Or do your anchor too?
Sometimes galvanizers charge extra to remove the old zinc. It is not possible to just "galvanize over the top" of old galvanizing, as it is an alloying reaction between steel and molten zinc. If the steel is not "visible" to the molten zinc, but covered with old zinc, it doesn't work. The old zinc is stripped off in the same hydrochloric acid that's used to clean the steel. But zinc consumes a lot of acid, compared to just cleaning steel, hence the extra change. This is often 60% on top of the galvanizing price.
So, to re-galvanize chain that still has some zinc..
50m of 8mm chain weighs about 70kg.
70kg x (£0.50 x 1.6) = £40
Price for new chain, 50m of 8mm - about £250
Rust is not a problem to a galvanizer (unless so thick that the integrity of the chain is in doubt). As Vyv said, the cleaning process (dilute hydrochloric acid) removes rust, and also residual zinc from the previous galvanizing.
Most galvanizers have a minimum order charge - they're used to dealing with customers who have truckloads of stuff, many tonnes at a time. (About 500-600 tonnes of steel a week is galvanized between the five galvanizing plants in Scotland). Those plants are in Elgin, Cumbernauld, Forfar, and two in Glasgow. (see link from the trade association website someone has posted)
Chain can be done in a plant that has a spinner (centrifuge) plant (there's only one in Scotland, it's in Elgin), or can be vigorously agitated as it comes out of the zinc, throwing the surplus zinc off before it solidifies.
There are two main layers to a galvanized coating, the alloy layer - thinnest and next the steel, and the zinc layer, on top. Zinc is softer than steel, alloy is harder than mild steel. Both are equally good at corrosion protection.
The minimum charge amount varies between companies, from £60 to £100. Typical rate for the galvanizing other than the minimum charge is £0.50/kg of steel. (In order to confuse the price, a base price plus various surcharges are quoted, but you really only are interested in the total price, not what those pricing mechanisms are)
It is NOT priced on the zinc weight added (as mentioned above), but on the finished weight of the whole item.
8mm chain weighs about 1.4kg/m, so a 50m chain might weigh about 70kg, and cost about £35 for the galvanizing. But you'd pay the minimum order charge. So doubling up the order with a mate, or doing two chains would make this better value.
Or do your anchor too?
Sometimes galvanizers charge extra to remove the old zinc. It is not possible to just "galvanize over the top" of old galvanizing, as it is an alloying reaction between steel and molten zinc. If the steel is not "visible" to the molten zinc, but covered with old zinc, it doesn't work. The old zinc is stripped off in the same hydrochloric acid that's used to clean the steel. But zinc consumes a lot of acid, compared to just cleaning steel, hence the extra change. This is often 60% on top of the galvanizing price.
So, to re-galvanize chain that still has some zinc..
50m of 8mm chain weighs about 70kg.
70kg x (£0.50 x 1.6) = £40
Price for new chain, 50m of 8mm - about £250
Niander
Well-Known Member
Ok thanks some good info there i have 2 chains and some other bits so could do the minimum order
which one would you recommend in Glasgow? maybe easiest as id be passing through on my way down south?
which one would you recommend in Glasgow? maybe easiest as id be passing through on my way down south?
Signed Out
Well-Known Member
Shame my chain's down in England, not with the boat up your way, or else would've asked to help you build that weight up to minimum order...
charles_reed
Well-Known Member
Actually more usually phosphoric acid.
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I can recommend Scottish Galvanisers Ltd. I had a couple of largish bilge keels done there a few years ago.
I arranged to take the keels in AM and picked them up PM same day.
They did a good job and so far the finish is fine.
Dave
I arranged to take the keels in AM and picked them up PM same day.
They did a good job and so far the finish is fine.
Dave
bikedaft
Well-Known Member
jock fleming at fpm henderson have used him for new and 2nd hand chain for many years
MM5AHO
Well-Known Member
No, phosphoric acid is not used in the galvanizing process.
It is used in many other surface coating processes, such as powdercoating, electroplating, but not in galvanizing.
vyv_cox
Well-Known Member
Not according to the professional galvaniser MM5AHO above, nor BE Wedge, a major galvanising company, who I used for my chain and who provided me with much of the information used in my article.
The UK Galvanisers Association also state that hydrochloric acid is used to remove rust and mill scale http://www.galvanizing.org.uk/index.php?cms_id=312§ionTitle=Process
Maybe you need to correct them?
Last edited:
Bosun Higgs
N/A
There are a number of things that the pre cleaning bath wont remove inc most paints. You need bare rust free steel going into the zinc bath to get something galvanised - it is not like an extra layer of paint, it forms an "alloy" with the steel at the surface.
MM5AHO
Well-Known Member
On types of Acid:
In the UK, Europe and many countries east of here, Hydrocloric acid is the most commonly used cleaning acid in galvanizing.
In North America, Sulphuric acid is more common.
Both work equally well, but the availability and price of these acids is what determines which is used in any one area.
Both are used as strengths from about 12% and reducing. When all acid becomes iron chloride / sulphate the acid is "spent" and sold for recycling or other uses (such as water treatment).
In the UK, Europe and many countries east of here, Hydrocloric acid is the most commonly used cleaning acid in galvanizing.
In North America, Sulphuric acid is more common.
Both work equally well, but the availability and price of these acids is what determines which is used in any one area.
Both are used as strengths from about 12% and reducing. When all acid becomes iron chloride / sulphate the acid is "spent" and sold for recycling or other uses (such as water treatment).
vyv_cox
Well-Known Member
I assume it is not economic to recover the zinc in solution that is removed in re-galvanising?
awol
Well-Known Member
Highland Colour Coaters in Cumbernauld send chain to their branch in Elgin (and the spinner) and it takes about a week. I once saw chain done without this benefit and it was returned as one concentrated pile closer to sculpture than chain - the owner spent over a week bashing it with a hammer before he gave up.
