Side anodes

[fudd]

Good morning. I need to have anodes on the side of Hunter. Is it best to have them underneath or on the side? If they go on the side are there any locks or restrictions that could cause problems? I've heard of one or two locks that may be a bit tight.

[nicknorman]

Normal practice is to put them on the sides of the boat where it's not at full width ie the tapering part of the bow or stern. If you put them mid way along on the sides or bottom they will get ripped off or jam the boat, unless you boat never moves or is on a river or other wide deep navigation.

[fudd]

I'm on the Stort but I will be moving quite a lot. The sides are straight. I did think about having one right in the middle of the base plate. It might stay on a bit longer.

[ditchcrawler]

We have a pair half way down the hull just above the base plate. If I drop a plumb line from the widest part of the hull, the rubbing strakes, they fall inside it. However I have had them hit the gate on one of the Napton locks so it must lean in a long way at the bottom. If/when they need replacing I will get the thinnest ones I can and have them welded on inside out, bending and extending the steel mounting bare in necessary. See sketch below

 

 

[GUMPY]

On my present boat we have recessed "boxes" for centre anodes. On previous NB they were on the baseplate and despite being 2'9" draft and ballasted flat never got ripped off by the bottom of the canal

[fudd]

We have a pair half way down the hull just above the base plate. If I drop a plumb line from the widest part of the hull, the rubbing strakes, they fall inside it. However I have had them hit the gate on one of the Napton locks so it must lean in a long way at the bottom. If/when they need replacing I will get the thinnest ones I can and have them welded on inside out, bending and extending the steel mounting bare in necessary. See sketch below

I wish I'd read your post before they were welded on.

 

[casper ghost]

Anodes on the sides are a complete waste of time. Anodes only work over a very short area so you'd need them all over the place. Don't waste your tine and money.

Casp'

On my present boat we have recessed "boxes" for centre anodes. On previous NB they were on the baseplate and despite being 2'9" draft and ballasted flat never got ripped off by the bottom of the canal

problem with recessed boxes is that the anode only protects the box, it won't work on the actual side of the boat.

[FadeToScarlet]

I could put some on the sides, as I've some very large dents that Severn and Canal and then Waterways put into the plating between the knees- the hull sides are very corrugated. But it's probably not worth bothering, I've not got any on the ends either.

[LEO]

Hi,

 

On the sides, you can get new anodes which have bevelled edges which make life easier.

 

You can't win with anodes, when I first got my boat 10 years ago a helpful Surveyor said anodes were needed to protect the sides. I had a hull survey a month ago (on a 48ft boat, 2 at the front, 2 pairs down the sides and 2 at the rear) and he said I had too many anodes, these caused the blacking to become soft at the waterline..........and pointed to some shiny bare metal areas.

 

The boat had just been pressure washed!.

 

Interestingly the steelwork had not lost a mm. in the years since it was built in 1998.

 

I think the advice given by the first Surveyor was the most helpful.

 

L

Edited May 21, 2016 by LEO

[Alan de Enfield]

Hi,

 

On the sides, you can get new anodes which have bevelled edges which make life easier.

 

You can't win with anodes, when I first got my boat 10 years ago a helpful Surveyor said anodes were needed to protect the sides. I had a hull survey a month ago (on a 48ft boat, 2 at the front, 2 pairs down the sides and 2 at the rear) and he said I had too many anodes, these caused the blacking to become soft at the waterline..........and pointed to some shiny bare metal areas.

 

The boat had just been pressure washed!.

 

Interestingly the steelwork had not lost a mm. in the years since it was built in 1998.

 

I think the advice given by the first Surveyor was the most helpful.

 

L

 

Nothing to do with diesel floating on the water then.

[LEO]

 

Nothing to do with diesel floating on the water then.

 

Hi,

 

There is that possibility, the shiny areas were small and obviously the blacking had been removed by the pressure washer.

 

Might be another Surveyor's 'fad', we had them every so often when I worked as one (HAC and beam lenght was one), but as said, I preferred the first Surveyors informal opinion..

[ditchcrawler]

Anodes on the sides are a complete waste of time. Anodes only work over a very short area so you'd need them all over the place. Don't waste your tine and money.

Casp'

problem with recessed boxes is that the anode only protects the box, it won't work on the actual side of the boat.

Not worth putting them on the front ether then.

[Bee]

'You can't win with anodes' Very True. I have anodes scattered about here and there, its like religion, don't really believe in it but might as well have a few just in case. I don't think they are worth the bother on the sides but a couple on the bow won't hurt. When there are dissimilar metals around though its different, I would always take professional advice when it comes to bronze prop, stern gear, water inlets etc. MG Duff are the people to ask.

[casper ghost]

Not worth putting them on the front ether then.

Correct.. The only place they can do any good is right at the back, where there are more nobel metals to act, like stainless and bronze.

Casp'

[system 4-50]

If you attached copper wires to the inside of your steel hull at the point where your anode was attached and at points sat 12 ft away, could you extend the area protected by the anode? By making the circuit "bigger"?

[Dalslandia]

Just saw an ad that said the boat had longlife anodes, either they are big or wrong sort.

In sweet water magnesium is best, in sweet/salty aluminum is said to be best, and in salt waters, zink is used, if they are not corroded away they don't work as good as they should, or no galvanic is happening with the boat, or miss placed.