Vactan/Fertan and blacking

[Starcoaster]

I have a couple of scrapes to my blacking that are showing through as rust, that I want to touch up.

Is it ok/ best to Fertan them first and then touch up with blacking, or should I just touch up the blacking directly (after scraping off any excess rust, obviously)?

Is there anything to stop you using Fertan with blacking, or is it just a case of personal choice? I already have Fertan so it's not going to be any hardship to do it with that first before I do the blacking itself, so that's not an issue.

 

**Edit

Also, can you black over paint? I want to black up to the gunnels and there's a layer of my regular paint already there. Again, after scraping off any loose or flaking bits.

Ta!

Edited April 26, 2013 by Starcoaster

[MtB]

Is it ok/ best to Fertan them first and then touch up with blacking, or should I just touch up the blacking directly (after scraping off any excess rust, obviously)?

Be fine to black straight onto the rust. I doubt Fertan would chemically fight with the blacking but I don't see any point.

**Edit

Also, can you black over paint? I want to black up to the gunnels and there's a layer of my regular paint already there. Again, after scraping off any loose or flaking bits.

Ta!

Yes, you can black over anything. How long it stays on for depends on how well the anything is stuck on.

 

 

MtB

[Timleech]

Be fine to black straight onto the rust. I doubt Fertan would chemically fight with the blacking but I don't see any point.Yes, you can black over anything. How long it stays on for depends on how well the anything is stuck on.

 

 

MtB

 

I don't know about Vactan, but bitumen doesn't hold well onto some rust converters.

 

Best to remove as much rust as possible, especially if it's scale rather than just a brown rust film, and black straight on to the steel.

 

Tim

[bizzard]

I've only used Fertan beneath ordinary oil based primers and top coats but I have used Jenolite which I expect has the similar ingredient ''Phosphoric acid'' in it on hulls under Bitumen and its been fine. When its thoroughly dry and gone black a slightly glazed finish will be left and I abraised this a little with 50 grit paper before applying the bitumen. But ideally I'd buzz out as much of the rust as possible first with an angle grinder and wire cup brush.

[MtB]

I've only used Fertan beneath ordinary oil based primers and top coats but I have used Jenolite which I expect has the similar ingredient ''Phosphoric acid'' in it on hulls under Bitumen and its been fine. When its thoroughly dry and gone black a slightly glazed finish will be left and I abraised this a little with 50 grit paper before applying the bitumen. But ideally I'd buzz out as much of the rust as possible first with an angle grinder and wire cup brush.

 

C'mon Bizz, do you REALLY think Starry is gonna have a little with 50 grit paper and an angle grinder and wire cup brush lying around in Springy, in amongst all the kittens and pink unicorns?

 

 

MtB

[NB Lola]

Scratches clear of the waterline- above the rubbing strikes - we use hammerite black straight to rust, works fine

[bizzard]

C'mon Bizz, do you REALLY think Starry is gonna have a little with 50 grit paper and an angle grinder and wire cup brush lying around in Springy, in amongst all the kittens and pink unicorns?

 

 

MtB

Who knows Mike, she's got the Fertan great motor bike she could well have an angle grinder tucked away somewhere. You could always lend her yours.

[Timleech]

Who knows Mike, she's got the Fertan great motor bike she could well have an angle grinder tucked away somewhere. You could always lend her yours.

 

She's not likely to have any 50 grit paper, so far as I know it's not a standard grit

 

Re painting over gloss, yes it's usually OK but you can sometimes get lifting of the edges where the paint has been chipped. Yes rub back the chipped edges to make that less likely.

 

Tim

[Kwacker]

We used Tank Blacking over Vactan (active ingredient Tannic Acid) in the water tank ... works a treat.

From its name, I would assume Fertan is also tannic acid based.

[Starcoaster]

Ok, cool. The rust isn't bad or deep, so I was just going to sand it over (with sandpaper that I just bought, in two degrees of roughness- one quite smooth and the other one almost as bad as that bog roll they use in schools) then slap on whatever it is.

I have the Fertan but not the blacking yet so I was planning on just doing the fertan bits this weekend, but now I am not sure.

I'm not planning on angle grinding and shiny scrapy powertooling the paintwork I intend to go over on the top half of the boat, so there's no chance of my finding out what those mentioned tools are and whining until I convince MB it needs to be done if only to shut me up and then supervising him doing it doing it to the blacking part!

Edited April 27, 2013 by Starcoaster