Anodes UK on the Sea

Bigplumbs

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My boat is moored on a Swing mooring for 6 months of the year May - Oct on the River Deben, Felixstowe. I am a cheapskate and don't like wasting money. My anodes (New last year) while degraded look like over half is left.

I was wondering if they will do for this year (Another 6 months)

How long do others get from their anodes

Regards

Dennis
 
My boat is moored on a Swing mooring for 6 months of the year May - Oct on the River Deben, Felixstowe. I am a cheapskate and don't like wasting money. My anodes (New last year) while degraded look like over half is left.

I was wondering if they will do for this year (Another 6 months)

How long do others get from their anodes

Regards

Dennis

It is largely irrelevant how long anodes last on other boats in other situations. For your decision the only thing that matters is how long they last on your boat, then you can assess how long before you need to replace based on past usage rate. If you have used less than a half in one season then it is reasonable to expect the rest will last a similar period in the future, although the more risk averse may take the view that one season experience is not enough data and fit new now to see what the rate is this year.
 
It is largely irrelevant how long anodes last on other boats in other situations. For your decision the only thing that matters is how long they last on your boat, then you can assess how long before you need to replace based on past usage rate. If you have used less than a half in one season then it is reasonable to expect the rest will last a similar period in the future, although the more risk averse may take the view that one season experience is not enough data and fit new now to see what the rate is this year.

Thanks for your response. I would still however like answers from others to the question I asked

Dennis
 
No use to you whatsoever but.......

Torquay Marina. Approx 1/3 wear every year for past 6 years. I still change for new every year.
 
Thanks for your response. I would still however like answers from others to the question I asked

Dennis

OK.

My last boat the anode on the saildrive lasted 6 years in the Med in the water 7 months a year, and 4 years in UK waters in the water all year round. Current boat has an anode twice the size and so far has worn less than 50% in 2 1/2 years in the water.

There are two strategies with anodes. Either, as I suggested, and as I do - monitor the wear rate and replace when you judge there is not enough to last until the next haulout. Or you do as others have posted and change every year. Both are equally valid approaches, the latter quite common as on many boats the anodes will not last reliably for 2 seasons.
 
I understand that if they are half gone consider them spent. As for rate of wear mìne erode at hugely different rates. For instance those on my trim tabs see almost no wear. Those on the brackets and H frames last easily 2 years before a third gone. Those on my lower leg next to the props will not see 6months in the water. I have SS props which contribute to this I'm sure, the point being that the rate of wear differs radically even within a meter and half distance.
 
When I first got my boat - the ring anode behind the props (stainless steel) lasted 3 months and was totally gone
I moved marinas and added another anode on the drive - put a gopro camera in the water to have a look (saves on lifting the boat out) after 3 1/2 months and the new ring anode was 80% still intact.
lifted the boat out after 8 months in the water and the anode was almost gone.
This season I have added another anode for further protection and have made a hanging anode and will use the old trim tab anodes that still have life in them.

Jon
 
When I first got my boat - the ring anode behind the props (stainless steel) lasted 3 months and was totally gone
I moved marinas and added another anode on the drive - put a gopro camera in the water to have a look (saves on lifting the boat out) after 3 1/2 months and the new ring anode was 80% still intact.
lifted the boat out after 8 months in the water and the anode was almost gone.
This season I have added another anode for further protection and have made a hanging anode and will use the old trim tab anodes that still have life in them.

Jon

Hanging anode? What did you connect it to on the boat.
 
Excellent find thank you Martin.

I'm feeling somewhat smug as I swapped to aluminium anodes this year as recommended in the article.

I'll keep an eye on them to check they still work. An added bonus is they were about half price compared to zinc anodes..

Nick

Your boat sits on its trailer (most of its life) :) you need to get some air anodes

Dennis
 
Thanks for your response. I would still however like answers from others to the question I asked

Dennis
Ring anode on VP 120s saildrive renewed last season. Hardly any visible loss so far. I think the last one lasted about 5 years and only replaced as I had work done on the oil seals.
This is on a swinging mooring at Slaughden, so I guess a similar situation to yours.
 
I was wondering the same

Dennis

You attach it electrically to the object you want to protect and then hang it in the water as close as possible to that item. So, for saildrives and outdrives that means the housings that your normal anode is connected to. The problem of using one is usually finding a way of running the cable to the housing and ensuring electrical continuity while also arranging it so the anode can be lifted out of the water when you are using the boat. MG Duff make hanging anodes.

In practice, rarely used as most anodes last long enough to give protection between haulouts, but can be useful if anode wear is really heavy (although that usually means something else is wrong) or the boat is in the water for extended periods. However, the usual hanging anode is relatively small and not normally as effective as proper underwater anodes. The anode that is closest to the object that it is protecting wears first. So the ones attached to the housing will go first and then maybe the hanging anode will take over.

In reality one just has to accept that anodes are consumables and work out how best to keep them protecting your boat consistent with your pattern of usage. As many have said, outdrives and to an extent saildrives are vulnerable simply because of the material used, plus replacement cost is high, so it is false economy to skimp on replacement anodes.
 
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