Which Blacking?

[Sea Dog]

4 hours ago, Cheshire cat said:

There's just an empty space in Midland Chandlers where the Intertuff should be so you might have to search around

Did you look on the outside wall or under the floor?

 

 

That's where my blacking is...

 

[ditchcrawler]

22 hours ago, mark99 said:

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

 

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

 

 

Whats the shelf life, 2 years? ?

[Sea Dog]

26 minutes ago, ditchcrawler said:

Whats the shelf life, 2 years? ?

In excess of 50 years if you paint the shelf with it...

[beerbeerbeerbeerbeer]

get an iron hull in the first place and save the grief ?

 

[David Mack]

I looked at Keelblack. Applying the stuff seemed straightforward and quick, but the thing that put me off was the need to clean off all surface rust, apply Fertan, and wash off the unreacted Fertan before the blacking could start. The extra time in preparation and applying the Fertan more than negated the time saving of the Keelblack itself, and the cost including the Fertan was uncompetitive. So I went with Ballistic Black.

[Richard10002]

12 hours ago, David Mack said:

I looked at Keelblack. Applying the stuff seemed straightforward and quick, but the thing that put me off was the need to clean off all surface rust, apply Fertan, and wash off the unreacted Fertan before the blacking could start. The extra time in preparation and applying the Fertan more than negated the time saving of the Keelblack itself, and the cost including the Fertan was uncompetitive. So I went with Ballistic Black.

Could you have used Vactan? Just let it dry..... no need to wash off.

 

I clean off the surface rust as best I can, and apply Vactan to any remaining orange bits. First coat of bitumen next day. Then a coat a day for the next 3 or 4 days.

 

No big deal in terms of time, if you’re out for a week, or longer.

[David Mack]

23 minutes ago, Richard10002 said:

Could you have used Vactan? Just let it dry..... no need to wash off.

 

I clean off the surface rust as best I can, and apply Vactan to any remaining orange bits. First coat of bitumen next day. Then a coat a day for the next 3 or 4 days.

 

No big deal in terms of time, if you’re out for a week, or longer.

 

I wondered that, but the instructions were very clear that you should use Fertan. I wondered if there might be compatibility issues using another product.

Edited September 3, 2020 by David Mack

[WotEver]

20 minutes ago, David Mack said:

 

I wondered that, but the instructions were very clear that you should use Fertan. I wondered if there might be compatibility issues using another product.

That’s possible. Vactan acts as an acrylic primer whereas Fertan doesn’t - it only passivates the rust. 

I guess you could ask the manufacturers of Keelblack?

[Richard10002]

10 hours ago, WotEver said:

That’s possible. Vactan acts as an acrylic primer whereas Fertan doesn’t - it only passivates the rust. 

I guess you could ask the manufacturers of Keelblack?

Agree that the question could be asked.

 

The instructions say to "prime" with Fertan:

 

"Old steel surfaces should be pressure washed clean, all marine growth removed and freed of flaking material with a scraper. Heavy rust should be wire-brushed or ground back to bare steel. Care should be taken not to over polish the steel. Prime bare or rusty steel with Fertan in accordance with themanufacturer’s instructions and allow the chemical reaction to work for 24 hours. After this period, the Fertan must be thoroughly washed off the treated surface before Keelblack is applied". 

 

I don't think Fertan primes, In the true sense of the word, whereas Vactan does. 

[Dr Bob]

15 minutes ago, Richard10002 said:

I don't think Fertan primes, In the true sense of the word, whereas Vactan does.

Fertan does not prime. It is a rust converter. nothing more. Wash it off and then put a paint system on (which then is better if there is a primer or a first coat that wets the surface well).

Vactan is a rust converter and a primer in one so doesnt need washing and you can then topcoat.

The user really needs to work out what he wants to do as usually trying to combine two tasks in a paint is a compromise. Therefore in this case, will the Vactan really wet out the surface properly and remain liquid enough to get into all the tiny cracks via capilliarly action as the fertan does? I havent a clue. I have never used Vactan so cant comment on long term protection performance but I do have lots of experience of fertan and it does work very well as it really does wet out the rust properly and then you can choose a 'proper' primer made by a proper paint company. My guess is that Vactan will never penetrate the rust as well ......but fertan has the huge disadvantage in that you waste an extra day, washing the treatment off and then drying it. THat is a real pain down the engine hole. I have stuck to Fertan despite the extra days work as I dont like 'compromises' in paint systems.

[Richard10002]

59 minutes ago, Dr Bob said:

Fertan does not prime. It is a rust converter. nothing more.

I agree.

 

I was commenting on the manufacturers use of the word "prime" with respect to the application of Fertan.

 

[Dr Bob]

8 minutes ago, Richard10002 said:

I agree.

 

I was commenting on the manufacturers use of the word "prime" with respect to the application of Fertan.

 

Yes, I agree. They are clearly wrong to use the word prime. Well spotted!

[matty40s]

3 minutes ago, Richard10002 said:

I agree.

 

I was commenting on the manufacturers use of the word "prime" with respect to the application of Fertan.

 

When Keelblack first came out, they hadnt even consulted the Fertan producers for relevant information on waiting 48 hours for it to cure. 

Therefore they wrongly stated that it would reduce docking times, even when wet.

One of the directors then started to post on here with glowing reviews, and it went downhill from there. A chandlery I know had stock sat there for 2 years....as nobody at Keelblack had said it goes hard after 6 months.

 

So , yes, applied in Summer, with a decent temperature and full Fertan drying time, along with washing it off....it might work. 

But for most boatyards with tight schedules, and the misinformation it started off with, I wouldnt use it, or recommend it.

[Markinaboat]

On 01/09/2020 at 23:01, Dr Bob said:

I've been hearing some good stuff about Keelblack.

DON'T!

[peterboat]

I think my advantage has always been that I was covering zinga blacking rather than something else, I always applied zinga over damage then 3 coats of keelblack.  I and my mate John are happy with it, he is covering old 2 pack and has done the whole derusting routine with success