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Which Blacking?


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Yes, Ballistic can go over Intertuf.

Types of Blacking is a dark art when every 2 years you put your faith in a product which isnt always there 2 years later....Ballistic has some good press on here, but not enough yet for me to plump for it when I come to covering the few holes in my Comastic.

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Until you lift the boat out every 2 or 3 years you don't know what's going on underwater anyway (I don't mean just the anti-corrosion coating, whatever it is).

 

If, for peace of mind, you are lifting/slipping the boat every so often, you might as well apply blacking (any make) while you are at it, then you know.

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14 hours ago, mark99 said:

Pssst wanna buy some Comastic?........

 

Grabbed a few tins before it was deleted.  Won't sell though!

 

 

I'll set the Thought Police on you, then.

Methinks it's agin the law to actually paint it on / apply it...

Have you anything to say in mitigation?

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Just now, peterboat said:

I have keelblack on and its working well so next year I will apply it again, its quick easy and 3 coats including the baseplate in a day.

I know there is a lot a opposition to keelblack on here with many examples of why it is bad.....but I had a good chat with a guy who has a lot of experience with it......and basically you have to forget your normal practices of blacking. If you do it right then it sounds like it could work very well.

First up, it sounds like the product has a short shelf life. Now, I worked as the tech manager of the Coatings group of a major multinational and understand what happens with a short shelf life coating product. Great when first made but six months down the road, the chemistry doesnt work and the protection is seriously compromised even though it can be applied no problem. Now I havent a clue what the shelf life is for Keelblack but the guy who I talked to runs a chanderlary and he ALWAYS orders it fresh to order and never keeps stock. He only accepts fresh dated product. He reckoned a 6 month old can would be no good. Is that why a lot of peeps have had a big problem with it?

Secondly, it is applied differently to the norm. It goes on very thin and needs multiple coats......but as Pete says above you can do 3 coats per day. It sounds very easy to apply so you just keep going round and round the boat. It's claimed to be water tolerant so that has to be useful in the sort of weather we get in the UK. For me, and my experience of formulating surface tolerant coatings, they can work well when you are only looking for a few years performance (so a real compromise if you are looking for a 2 pack surface tolerant epoxy to last 10 years) so maybe a good choice for a 2 year blacking cycle. Are peeps trying to put it on as per normal blacking and just not getting it on right?

I need to black mine next summer and at the moment my inclination is to try Keelblack.

Despite my experience developing 2 pack epoxies, I had our new boat blacked instead of 2 packed as I want to take it out of the water every few years to inspect it so the cost/benfit of 2 packing is reduced. Maybe in a few years I will get it zinc sprayed and epoxied but its not top priority now. Maybe keelblack will be the solution.

 

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8 minutes ago, Dr Bob said:

I know there is a lot a opposition to keelblack on here with many examples of why it is bad.....but I had a good chat with a guy who has a lot of experience with it......and basically you have to forget your normal practices of blacking. If you do it right then it sounds like it could work very well.

First up, it sounds like the product has a short shelf life. Now, I worked as the tech manager of the Coatings group of a major multinational and understand what happens with a short shelf life coating product. Great when first made but six months down the road, the chemistry doesnt work and the protection is seriously compromised even though it can be applied no problem. Now I havent a clue what the shelf life is for Keelblack but the guy who I talked to runs a chanderlary and he ALWAYS orders it fresh to order and never keeps stock. He only accepts fresh dated product. He reckoned a 6 month old can would be no good. Is that why a lot of peeps have had a big problem with it?

Secondly, it is applied differently to the norm. It goes on very thin and needs multiple coats......but as Pete says above you can do 3 coats per day. It sounds very easy to apply so you just keep going round and round the boat. It's claimed to be water tolerant so that has to be useful in the sort of weather we get in the UK. For me, and my experience of formulating surface tolerant coatings, they can work well when you are only looking for a few years performance (so a real compromise if you are looking for a 2 pack surface tolerant epoxy to last 10 years) so maybe a good choice for a 2 year blacking cycle. Are peeps trying to put it on as per normal blacking and just not getting it on right?

I need to black mine next summer and at the moment my inclination is to try Keelblack.

Despite my experience developing 2 pack epoxies, I had our new boat blacked instead of 2 packed as I want to take it out of the water every few years to inspect it so the cost/benfit of 2 packing is reduced. Maybe in a few years I will get it zinc sprayed and epoxied but its not top priority now. Maybe keelblack will be the solution.

 

Mine came both times direct from the maker in Newcastle the second time I stayed it on I did 2 boats in a day both fat boats. 3 coats up to just above waterline one on the sides gave good coverage, it goes on brown and changes to black as it dries so you know where you have been. I don't keep spare I just use it on the job.

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22 minutes ago, Dr Bob said:

 

I need to black mine next summer and at the moment my inclination is to try Keelblack.

That should be an interesting and informative experiment given your experience Bob.

 

I still can't understand why the manufacturer hasn't coated a couple of boats correctly, slipped them regularly to provide photographic evidence of its performance  and used this to vouch for its product. Is this a glaring error or a deliberate dodge I can't help but wonder.  Without this, the only positive evidence I have is @peterboat 's assertion of how good it is (but it's applied over fresh Zinga in his case, iirc).

 

My only experience has been the 2 boats I've seen out of the water myself. The first was being surveyed with Mr Fertan also in attendance after a swift and disastrous failure about 3 years ago. The second, last year, was out of the water again after 6 months because it was falling off - what was left was removed with a household pressure washer.  Both may have been down to incorrect application, but I seem to remember ease of application being a selling point. Sticky old bitumen wouldn't fail that quickly or that badly, even when done by a proper Muppet, would it?

 

 

Edited by Sea Dog
Added 'positive'
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1 minute ago, Sea Dog said:

That should be an interesting and informative experiment given your experience Bob.

 

I still can't understand why the manufacturer hasn't coated a couple of boats correctly, slipped them regularly to provide photographic evidence of its performance  and used this to vouch for its product. Is this a glaring error or a deliberate dodge I can't help but wonder.  Without this, the only positive evidence I have is @peterboat 's assertion of how good it is (but it's applied over fresh Zinga in his case, iirc).

 

My only experience has been the 2 boats I've seen out of the water myself. The first was being surveyed with Mr Fertan also in attendance after a swift and disastrous failure about 3 years ago. The second, last year, was out of the water again after 6 months because it was falling off - what was left was removed with a household pressure washer.  Both may have been down to incorrect application, but I seem to remember ease of application being a selling point. Sticky old bitumen wouldn't fail that quickly or that badly, even when done by a proper Muppet, would it?

 

 

Others on here have used it with great results as well as me, Jim Riley for one and others on the numerous threads about blacking 

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7 minutes ago, Sea Dog said:

Both may have been down to incorrect application, but I seem to remember ease of application being a selling point. Sticky old bitumen wouldn't fail that quickly or that badly, even when done by a proper Muppet, would it?

You have to watch when it claims ease of application. Keelblack pushes 'ease of application' as (as I understand it - but never seen it in action) it is very easy to roll on - ie it's application is less tiresome on the hands and arms. This is slightly different to the 'simple to apply' ie you dont have to worry about getting the old coating off, do it at the right temperature/humidity etc. Keelblack is certainly thin and easy to apply but perhaps the rest of the application needs to be done to the letter of the application instructions (so not tolerant of poor application).

 

I do worry about the shelf life though. Normal blacking is just a sticky mess that stays like that. Keelblack is (IIRC) a hydrocarbon mix dispersed in water. It is possible that the hydrocarbon bit can react with itself over time (and 6 months could be that time scale) and therefore change the properties of the emulsion - therefore not allowing it to stick to a surface or wet the surface out properly. Something is very wrong with it coming off with a low power pressure washer so I would suspect something has gone wrong with the chemistry of the  product. If that was the reason for the premature failures then the company making it would not be telling us as they wouldnt want the limitation on shelf life to be made public ...but would be doing all they can behind the scenes to extend the shelf life with anti oxidants (or similar)...but it is far from easy to do that.

 

I do know about short shelf life products. In the 80's, we developed a water tolerant and oil tolerant 2 pack epoxy for splash zone, external or water immersion duty, but the snag was it only had 6 months shelf life before the 'active' component decayed to the point where it wasnt protecting. It was a great product (when freshly made) and would have made us a lot of money......but the short shelf life made it non commercial. You may remember back in the 80's, BP made a polymer material that they could spray onto oil slicks in the sea which immediately solidified and you could role up the 'solid' oil like a carpet. It really did work - but the shelf life was 6 months. Useless to commercialise as it could not be stored at bases around the coast - it was expensive. It was the same chemical we had in our tolerant coating. What a bugger!

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1 hour ago, peterboat said:

Others on here have used it with great results as well as me, Jim Riley for one and others on the numerous threads about blacking 

I don't doubt your assertion at all - you're clearly a sensible and capable bloke, and you have had a good experience. Lack of shelf life and a limited tolerance when it comes to surface prep may well explain the (at best) mixed reviews. Doesn't make it an inherently poor product, just one that's possibly not as well understood as it needs to be.

 

This goes back to my main issue: why hasn't the manufacturer done the obvious and carried out trials in this environment and used the results in its marketing?  To me, even several years after going to market, it seems that each customer is still a guinea pig.

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10 minutes ago, Sea Dog said:

I don't doubt your assertion at all - you're clearly a sensible and capable bloke, and you have had a good experience. Lack of shelf life and a limited tolerance when it comes to surface prep may well explain the (at best) mixed reviews. Doesn't make it an inherently poor product, just one that's possibly not as well understood as it needs to be.

 

This goes back to my main issue: why hasn't the manufacturer done the obvious and carried out trials in this environment and used the results in its marketing?  To me, even several years after going to market, it seems that each customer is still a guinea pig.

I have no idea why others had issues with it, my first time I steam cleaned and applied second time same again, the steam cleaner didnt remove the first keel black. I do repairs to the zinga where I have removed it by impact, next year is a blacking year and repaint as well, I will be 63 then so the paint should last me to the end of my boating years, blacking well I will have a few more coats to apply I suspect 

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5 hours ago, Dr Bob said:

Despite my experience developing 2 pack epoxies, I had our new boat blacked instead of 2 packed as I want to take it out of the water every few years to inspect it so the cost/benfit of 2 packing is reduced.

 

There we have the voice of a credible expert. I'll go on blacking my boat every 2-3 years - thank you! 

4 hours ago, Dr Bob said:

My ecofan (other models are available) is working great again this autumn.

 

But AFAIK you're not a thermodynamicist!

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42 minutes ago, Machpoint005 said:

 

There we have the voice of a credible expert. I'll go on blacking my boat every 2-3 years - thank you! 

 

But AFAIK you're not a thermodynamicist!

Same here even though its zingered it doesnt stop me hitting things and damaging the coating, far better to check it over every 3 years

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