Zinc anodes the more i search the more conflicted I feel

[Travellingwithtoby]

Hi guys and gals

So had a sudden realisation that I cannot check my anodes without taking a risk and jumping overboard on my own strapped on, and am adding electrical kit to my steel hulled ebbtide.....

I have spent all day reading conflicting posts about zinc etc

One post in particular specified using a half cell and a multimeter, and the purity of the water the boat is in.

But I cannot for the life of me find a straight forward. Put this here, measure this there guide?

If someone is happy to do the words I would happily take photos and make a guide as I'm sure many people would find it useful?

 

[VicS]

What precisely do you want to know.

The theory behind cathodic protection and the use of sacrificial anodes

What type of anode to use?

How many to fit to a steel hull ?

How to fit them?

How to check the level of protection with a reference electrode or half cell and a multi-meter?

Have you looked at MG Duffs website.... quite a bit of info there, .........and other anode producers websites

 

[VicS]

Some light reading :

Corrosion good practice guides

http://eprintspublications.npl.co.uk/8402/1/Corrosion Guide No 1.pdf

https://www.cathodic.co.uk/wp-content/uploads/2016/10/Cathodic-Protection-An-Overview-2.pdf

I have not read this but it looks interesting. https://www.cedengineering.com/userfiles/Intro to Cathodic Protection Inspection and Testing.pdf
(I'll read it if my house arrest under the CV 19 restrictions goes on beyond the summer)

I last did cathodic protection monitoring 58 years ago (using a copper/ copper sulfate half cell) so pleas dont ask me any questions about testing.

 

[pvb]

So had a sudden realisation that I cannot check my anodes without taking a risk and jumping overboard on my own strapped on, and am adding electrical kit to my steel hulled ebbtide.....

You shouldn't go overboard alone.

What sort of electrical kit are you adding? If you use shorepower, you should fit a galvanic isolator - this will help to prevent undue erosion of your anodes.

 

[rogerthebodger]

I have 4 anodes like this on each side of my hull and have been on since I launched in 2009.

On launching

One of my main points is to protect the steel with lots of of epoxy tar below the waterline and to have a little yellow metal as possible.

I changed my prop from bronze to one I fabricated from 316 stainless steel.

This was at the first liftout after one year.

 

[Travellingwithtoby]

What precisely do you want to know.

The theory behind cathodic protection and the use of sacrificial anodes

What type of anode to use?

How many to fit to a steel hull ?

How to fit them?

How to check the level of protection with a reference electrode or half cell and a multi-meter?

Have you looked at MG Duffs website.... quite a bit of info there, .........and other anode producers websites

So a basic, do this to check them without getting wet or lifting out/drying out with a half cell and meter would be amazing!

I have not seen that site but I will look it up!

Its mostly to make sure i don't make holes before i get her lifted out!

Some light reading :

Corrosion good practice guides

http://eprintspublications.npl.co.uk/8402/1/Corrosion Guide No 1.pdf

https://www.cathodic.co.uk/wp-content/uploads/2016/10/Cathodic-Protection-An-Overview-2.pdf

I have not read this but it looks interesting. https://www.cedengineering.com/userfiles/Intro to Cathodic Protection Inspection and Testing.pdf
(I'll read it if my house arrest under the CV 19 restrictions goes on beyond the summer)

I last did cathodic protection monitoring 58 years ago (using a copper/ copper sulfate half cell) so pleas dont ask me any questions about testing.

thank you for the light reading! I won't ask i promise haha

You shouldn't go overboard alone.

What sort of electrical kit are you adding? If you use shorepower, you should fit a galvanic isolator - this will help to prevent undue erosion of your anodes.

No I have had too once due to a blocked through Hull. But that was my only option and I took every precaution I could. Won't be doing it again!
So rewiring the 240v, 3kw inverter, 900w inverter, induction hob and small electric oven. 240v fridge and a small office

320w of solar, and Rutland 914i wind generator. Mounting a Honda 2.7 kva generator in its own vented locker with forced air for cooling

I belive I have a galvanjc isolater, can't get to it, but it appears to have the earth from the breaker box going to it? Anything i can check on it? Generator will be fed through the same circuit so as i don't have multiple breakers...

I have 4 anodes like this on each side of my hull and have been on since I launched in 2009.

On launching

One of my main points is to protect the steel with lots of of epoxy tar below the waterline and to have a little yellow metal as possible.

I changed my prop from bronze to one I fabricated from 316 stainless steel.

This was at the first liftout after one year.

Awesome, um so coppercoat I'm assuming safe as its meant to be unable to conduct through the epoxy?

Its a shame the water is so murky here!

Thanks so far guys! I'd be lost without your help ?

 

[status]

Not sure how you would test the anodes, but if you are concerned there may be no anode left and are not going anywhere you could hang an additional one or two over the side on a wire electrically connected to the hull.

We used to do this on an aluminium race boat I worked on, permanent anodes cause drag!

 

[Plum]

Not sure how you would test the anodes, but if you are concerned there may be no anode left and are not going anywhere you could hang an additional one or two over the side on a wire electrically connected to the hull.

We used to do this on an aluminium race boat I worked on, permanent anodes cause drag!

Yes, I hung one over the side just before lockdown as I knew my hull anode was almost gone and needed to postpone my planned anode change.

Www.solocoastalsailing.co.uk

 

[Rappey]

Buy a cheap waterproof camera and put it on a long pole ?

 

[Travellingwithtoby]

Buy a cheap waterproof camera and put it on a long pole ?

As I read that I remembered I have a small waterproof camera!