Is it necessary to black the bottom?

[Bee]

Doesn't seem to be any paint at all on it, strange that. Interesting about the anodes though, seems to suggest that all the 'rust' on the bottom is due to electrolytic effects. I doubt if all the paint loss was due to being scraped off though, if that was the case there should at least be some left here and there. My boat has a slight V bottom and for the first couple of years was in the UK and ground its way up the GU to Braunston and scraped its way to Guildford and Stratford on Avon as well as being steered into things on the Thames hardly lost any (epoxy) paint from underneath.

[rusty69]

 

The boat was blacked underneath by Fox's on the ML back in April 2012 and they only use long handle rollers to do it. 

Wow, wish the foxes round our way were that clever. If they'd used their brushes instead of rollers , you would have got a better job. 

Boom boom. 

Edited March 12, 2018 by rusty69

[ditchcrawler]

There is a post on Facebook that indicates that Comastic is no longer available

[Jrtm]

On 01/03/2018 at 10:45, Tim Lewis said:

We always black the bottom of Fulbourne, it is 81 years old and still has it’s original bottom!

Tim

My bottoms have no steel corrosion or pitting never blacked still going strong nearly 80 years on.

[jenevers]

On 11/03/2018 at 16:44, ditchcrawler said:

This was the bottom of Harnser when I was in Middlewich dry dock last autumn, I put the camera under the boat not my head. The boat was blacked underneath by Fox's on the ML back in April 2012 and they only use long handle rollers to do it. The interesting point is I have anodes half way down the sides of the hull and they line up where the bostock is and you can see a difference in the bottom in that area. You can also see how much of that black has been scraped off in five and a half years.

Interesting that the rust is in distinctly straight lines. Is that due to scraping the base plate on underwater objects as the boat was making way?

[dccruiser]

12 hours ago, ditchcrawler said:

There is a post on Facebook that indicates that Comastic is no longer available

Think intertuf has cornered that market aside from the name doesnt seem a lot different to comastic ... I have just blacked mine with keelblack , went on and cured well but the jury is out will report back on how well it lasts, but the thing that swung my decision was the boat that came out the same time as mine to have a new external skin tank was done in october with keelblack and it had no weed growth, snails or barnacles on the hull and with a quick walk round with a pressure washer looked like it had just been done, extremely impressive as most blacking turns grey within a few months yet this was as black as the stuff i was putting on.

Rick

[jenevers]

On 03/03/2018 at 11:08, blackrose said:

 

Edit: Actually I knew a bloke in the marina at Brentford whose form of isolation was deliberately not to bond his mains earth to his steel hull! But that's a whole "nuther" can of worms. 

Interesting. Actually, many mains appliance don’t even have an earth cable these days. Is that because many kettles etc are plastic, so there’s no way you could touch a metal part and possibly get a shock? I met someone who also didn’t bond his mains or 12 volt system to the hull. So far as I know, both he and his boat are still OK.

[dccruiser]

8 minutes ago, jenevers said:

Interesting. Actually, many mains appliance don’t even have an earth cable these days. Is that because many kettles etc are plastic, so there’s no way you could touch a metal part and possibly get a shock? I met someone who also didn’t bond his mains or 12 volt system to the hull. So far as I know, both he and his boat are still OK.

those without an earth are double insulated ... and a 30 milliamp RCCD will trip whether it be live and earth or earth and neutral that are crossed.

Rick

Edited March 13, 2018 by dccruiser

[Neil Smith]

Some appliances say no earthing  needed as its double insulated already.

Neil.