Thanks for an interesting video! One small point - bonding all the metal through hull components together doesn't seem necessary to prevent shock risk - you need at least 50V difference between two places someone can touch to drive a potentially fatal current through them and this seems very unlikely. If a boat was moored in such a strong electric field I think it would also very rapidly corrode any metalwork in the path, and the battery negative connection would also be irrelevant. Connecting the metalwork to shore power earth might help but would also mean bigger currents and faster corrosion.
I have a Fiber Glass boat. PropShaft has been removed there is a piece of bronze that's glassed in for the cutless bearing. This has a plastic cover on it. Should I put a zink close by or does it need to be in contact with the bronze. Thank you
You would be best to speak to a boat yard or surveyor for specific advice for your boat. The anode needs to be as close as possible to the metal it is protecting, and electrically bonded to it. So an anode protecting your prop and shaft should be within two or three feet of the prop and bonded to the gearbox and shaft inside the boat. Alternatively a anode directly attached to the propeller hub or the to the shaft will be bonded by direct contact.
So when you talk about a “season” can you be a little more specific, 6 months, a year. Why do I ask? A boat may not come out of the water but once per year or in autumn and then back in the water in the spring. So is once per year haul out and check adequate? And if we find the zincs less than 50% we need to increase the anode size or quantity.
A season is generally from spring launch to autumn/winter lift out, so around 6-8 months. Checking your anodes 'should' be a once a year task. If there's a problem, however, and the anodes are insufficient or are subject to stray current, they may not last that long, hence the 50% safety margin. You can always put a camera over the side, or swim on the boat to have a look how the anodes are doing. If they are more than 50% corroded, it's worth adding more, either in size or in number, and also checking you don't have any stray current
@@YachtingMonthly so season is actually meaningless if an individual boat is cruising throughout the year ... or year plus. The owner will have to self inspect and if needed change out while in the water. Stray current should be no issue provide the boat has a galvanic isolator unless the boat itself is the cause and recipient of the stray current, the boat becomes a sailing or powering battery and is a danger to itself. And if stray current appears to be an issue a tech with the appropriate test probes can quickly sort it all out.
Thank you for all these informations.Safety first.
You can replace them under water we dive inspect hulls and replace anodes all the time.
Thanks for an interesting video! One small point - bonding all the metal through hull components together doesn't seem necessary to prevent shock risk - you need at least 50V difference between two places someone can touch to drive a potentially fatal current through them and this seems very unlikely. If a boat was moored in such a strong electric field I think it would also very rapidly corrode any metalwork in the path, and the battery negative connection would also be irrelevant. Connecting the metalwork to shore power earth might help but would also mean bigger currents and faster corrosion.
Love when you post videos. Used to do the best reviews too!
I subscribed because of this information. Thankyou!
I have a Fiber Glass boat. PropShaft has been removed there is a piece of bronze that's glassed in for the cutless bearing. This has a plastic cover on it. Should I put a zink close by or does it need to be in contact with the bronze. Thank you
Hello, I love the video! Would you also be able tolet me know where to put the anodes? How many do I need on a 29meters long boat? Thanks in advance.
You would be best to speak to a boat yard or surveyor for specific advice for your boat. The anode needs to be as close as possible to the metal it is protecting, and electrically bonded to it. So an anode protecting your prop and shaft should be within two or three feet of the prop and bonded to the gearbox and shaft inside the boat. Alternatively a anode directly attached to the propeller hub or the to the shaft will be bonded by direct contact.
Is the teardrop, back to front???
Always make sure the zinc surface and contact surfaces are clean or they will not work
If you own a wooden yacht please don't bond your anodes internally.
How to change anodes on a tie bar
So when you talk about a “season” can you be a little more specific, 6 months, a year. Why do I ask? A boat may not come out of the water but once per year or in autumn and then back in the water in the spring.
So is once per year haul out and check adequate?
And if we find the zincs less than 50% we need to increase the anode size or quantity.
A season is generally from spring launch to autumn/winter lift out, so around 6-8 months. Checking your anodes 'should' be a once a year task. If there's a problem, however, and the anodes are insufficient or are subject to stray current, they may not last that long, hence the 50% safety margin. You can always put a camera over the side, or swim on the boat to have a look how the anodes are doing. If they are more than 50% corroded, it's worth adding more, either in size or in number, and also checking you don't have any stray current
@@YachtingMonthly so season is actually meaningless if an individual boat is cruising throughout the year ... or year plus. The owner will have to self inspect and if needed change out while in the water. Stray current should be no issue provide the boat has a galvanic isolator unless the boat itself is the cause and recipient of the stray current, the boat becomes a sailing or powering battery and is a danger to itself. And if stray current appears to be an issue a tech with the appropriate test probes can quickly sort it all out.
Thanks
Calling zinc less noble, is very hurtful.
He placed it the wrong direction it will cost some additional drag to boat
Step 1: buy fiberglass boat
Step 2: sell aluminum boat
Step 1: buy fiberglas boat
Step 2: sell aluminium boat
Step 3: sit on fiberglas boat and drink some beers 💫👍
thanks