Jump to content

DIY epoxy blacking.


rusty69

Featured Posts

19 minutes ago, rusty69 said:

So, trawling though previous threads, I found this comment from @Dr Bob Trust him. He's a dogtor. Anyone got a data sheet for the epifanes or ballastic?

 

 

 

Ballastic epoxy data.pdf 335.49 kB · 1 download

 

Yea, and my comments haven't changed.

Epoxies are hard rigid coatings that work by stopping oxygen and water getting to the substrate. They are excellent at the job due to their excellent adhesion to well prepared steel.

They will not work well over soft single pack coatings. You may get some years out of them but its a poor solution.

  • Greenie 1
Link to comment
Share on other sites

His reply really did ignore the details of what was being talked about, that the epoxy goes on a well prepared (but not totally bitumen free) surface, and that it wasn't meant to be the '10 year' job a traditional application of epoxy is rated for - it was in fact part of a more regular application that progressively improved. He's not wrong, but also not really on target.

 

However - I didn't end up using it, so can't report! What I DID end up using was Jotun Vinyguard as an 18" stripe at the waterline with tradition bitumen over the top. It's solvent based and melted into the existing bitch after a scrape/wash. 2 year report on that - brilliant stuff. The bitumen, as expected, had softened up a lot from diesel spills, and I had a forced ice cruise just before Christmas that stripped a lot off. The Vinyguard is completely intact, and a big improvement on just bitumen. Really no rust at all other than some gouges on rubbing strakes etc.

Link to comment
Share on other sites

9 minutes ago, Dr Bob said:

 

Yea, and my comments haven't changed.

Epoxies are hard rigid coatings that work by stopping oxygen and water getting to the substrate. They are excellent at the job due to their excellent adhesion to well prepared steel.

They will not work well over soft single pack coatings. You may get some years out of them but its a poor solution.

Hello doctor bob. Can I ask then, in your humble opinion, is grit blasting the only way to go to achieve an SA 2.5 finish?

2 minutes ago, barmyfluid said:

His reply really did ignore the details of what was being talked about, that the epoxy goes on a well prepared (but not totally bitumen free) surface, and that it wasn't meant to be the '10 year' job a traditional application of epoxy is rated for - it was in fact part of a more regular application that progressively improved. He's not wrong, but also not really on target.

 

However - I didn't end up using it, so can't report! What I DID end up using was Jotun Vinyguard as an 18" stripe at the waterline with tradition bitumen over the top. It's solvent based and melted into the existing bitch after a scrape/wash. 2 year report on that - brilliant stuff. The bitumen, as expected, had softened up a lot from diesel spills, and I had a forced ice cruise just before Christmas that stripped a lot off. The Vinyguard is completely intact, and a big improvement on just bitumen. Really no rust at all other than some gouges on rubbing strakes etc.

Can I ask why you chose not to use the ballastic in the end?

Link to comment
Share on other sites

6 minutes ago, barmyfluid said:

His reply really did ignore the details of what was being talked about, that the epoxy goes on a well prepared (but not totally bitumen free) surface, and that it wasn't meant to be the '10 year' job a traditional application of epoxy is rated for - it was in fact part of a more regular application that progressively improved. He's not wrong, but also not really on target.

I thought that was kind of the point though. The surface is not well prepared enough if it still contains traces of bitumen.

Edited by rusty69
Link to comment
Share on other sites

2 minutes ago, rusty69 said:

I thought that was kind of the point though. The surface is not well prepared enough if it still contains traces of bitumen.

I can't quite recall why I didn't, though when I arrived at the boatyard the first thing they offered me was to black her using epoxy over my bitumen (after a scrape and pressure wash), saying that's what they did as standard now.

 

There are 2 things being talked about here. 

 

1: The correct application of epoxy to a bare metal surface, giving maximum adhesion and longevity, up to 10 years. Following the instructions to the letter. There is no shortcut to this, and no snake oil solution. Dr Bob is right.

 

2: Scraping and washing loose bitumen off then applying epoxy. Repeat every 2 years. What comes off, comes off, and you're gradually getting better adhesion. But it's totally not scenario 1.

 

 

  • Greenie 3
Link to comment
Share on other sites

2 minutes ago, barmyfluid said:

I can't quite recall why I didn't, though when I arrived at the boatyard the first thing they offered me was to black her using epoxy over my bitumen (after a scrape and pressure wash), saying that's what they did as standard now.

 

There are 2 things being talked about here. 

 

1: The correct application of epoxy to a bare metal surface, giving maximum adhesion and longevity, up to 10 years. Following the instructions to the letter. There is no shortcut to this, and no snake oil solution. Dr Bob is right.

 

2: Scraping and washing loose bitumen off then applying epoxy. Repeat every 2 years. What comes off, comes off, and you're gradually getting better adhesion. But it's totally not scenario 1.

 

 

Yes, I guess like most people , I am looking for a compromise without the expense of grit blasting. Not ideal, but if it last a bit longer than bitumen, perhaps it is a worthwhile one. That is not to say, I won;t try and achieve the best preparation I can within the given time period.

 

I'm dreaming of your option 1, but will likely end up with option 2, or hopefully somewhere in between.

Link to comment
Share on other sites

3 minutes ago, rusty69 said:

Yes, I guess like most people , I am looking for a compromise without the expense of grit blasting. Not ideal, but if it last a bit longer than bitumen, perhaps it is a worthwhile one. That is not to say, I won;t try and achieve the best preparation I can within the given time period.

 

I'm dreaming of your option 1, but will likely end up with option 2, or hopefully somewhere in between.

That is what I'm aiming at. Luckily I've access to dry Dock facilities at very low cost. So can take the boat out every year if need be. Even with the full monty scrapes would have to be touched up anyway. The way I boat it would be every year. 🤣

  • Haha 1
Link to comment
Share on other sites

The benefit of opt 2 (as I see it) is that it's going to be better than bitumen for the 2(ish) years with regard to diesel spills. 2ish years is also when you should be checking your prop, anodes & hull anyway, it's not like you can say, 'right, that's it for 10 years...' and not bother hauling out.

 

Cons - expensive innit.

 

Seriously though, I'm well impressed with Vinyguard, which definitely IS meant to be used over bitumen.

  • Greenie 1
Link to comment
Share on other sites

 

1 minute ago, rusty69 said:

Yes, I guess like most people , I am looking for a compromise without the expense of grit blasting. Not ideal, but if it last a bit longer than bitumen, perhaps it is a worthwhile one. That is not to say, I won;t try and achieve the best preparation I can within the given time period.

 

I'm dreaming of your option 1, but will likely end up with option 2, or hopefully somewhere in between.

 

I wonder if it might be worth a quick call to your host (Clive?), and ask how much of the old bitumen comes off.

The thing is that if most of it is swept off by the very high pressure washer, the option of hiring a DIY sand blaster might start to make a bit more sense, as it would be a less physically  gruelling method for you to remove the final stubborn patches of bitumen that are clinging on. It might be the kind of thing that would add some lengevity to the epoxy treatment, without spending £1000 or more for a pro blaster.

I also like the sound of the sandblasting idea, as a way of cleaning rust out of any pits in the hull. 

 

  • Greenie 1
Link to comment
Share on other sites

1 minute ago, barmyfluid said:

The benefit of opt 2 (as I see it) is that it's going to be better than bitumen for the 2(ish) years with regard to diesel spills. 2ish years is also when you should be checking your prop, anodes & hull anyway, it's not like you can say, 'right, that's it for 10 years...' and not bother hauling out.

 

Cons - expensive innit.

 

Seriously though, I'm well impressed with Vinyguard, which definitely IS meant to be used over bitumen.

Oh dear. You mean I have to look into vinyguard now, as well 

1 minute ago, Tony1 said:

 

 

I wonder if it might be worth a quick call to your host (Clive?), and ask how much of the old bitumen comes off.

The thing is that if most of it is swept off by the very high pressure washer, the option of hiring a DIY sand blaster might start to make a bit more sense, as it would be a less physically  gruelling method for you to remove the final stubborn patches of bitumen that are clinging on. It might be the kind of thing that would add some lengevity to the epoxy treatment, without spending £1000 or more for a pro blaster.

I also like the sound of the sandblasting idea, as a way of cleaning rust out of any pits in the hull. 

 

Yes. I'll do that tomorrow. 

Link to comment
Share on other sites

8 minutes ago, rusty69 said:

Oh dear. You mean I have to look into vinyguard now, as well 

Yes. I'll do that tomorrow. 

 

Thanks for starting this thread Rusty (and to all the contributors), I think there will be loads of people like myself whose boats are coming due for blacking who will be taking a look and will really appreciate at the various options, advice and information explained here. 

 

Edited by Tony1
Link to comment
Share on other sites

Just now, Tony1 said:

 

Thanks for starting this thread Rusty, I think there will be loads of people like myself whose boats are coming due for blacking who will be taking a look at the various options, advice and information explained here. 

 

I think its probably all been said before, but I suspect more people are investigating the epoxy route. It probably does no harm to have an annual thread, as there are probably lots of people thinking about 2023 maintenance as you say. 

 

Unfortunately, its as different as lithium batteries are from LA. 

Link to comment
Share on other sites

First use one of these and about 3 packs of blades.  Start using it as soon as the hull is out of the water, still dripping.  Don't wait till the next day or even long enough to make a brew, get on with it immediately.

 

https://www.toolstation.com/prodec-advance-titan-heavy-duty-scraper/p75329

 

75329.jpg

 

Don't try and save a couple of quid on the cheaper handles, they are very uncomfortable to use for long periods and you have to faff with a screwdriver to change blades. DAMHIK ... 

 

After the first scrape, wash with a reasonable pressure washer - around 150 bar will do - then scrape again and wash again.

 

That'll get most (95%+) of the old bitumen off if you put enough effort in, although it's easier when it's soft and warm.

 

Then hit the hull with a whole box full of 75mm twisted strand cup brushes - steel not brass -  and a 4" angle grinder.  As soon as the brush starts getting clogged, fit another one.  Don't try and persevere with worn brushes or you'll not be correctly abrading the surface.  

 

That'll get nearly all the rest of the bitumen off. 

 

I tend to rope other people in to help, two or three extra bodies for a 60' boat means you can rest your arms occasionally!

 

It's seriously hard graft, but you'll be back to mostly bare steel by this point.  It's not Swedish Standard Sa2.5, I call it Swedish Chef standard (as done by a Muppet) but it's not fallen off yet.  

 

I use Hempel Hempadur 45143 with the cold climate curing agent - even in UK heatwaves it's the one to use.  The warm climate curing agent is for use much nearer the equator!

 

I'm on my second lot now, and I couldn't shift the first lot back to bare steel so figured if it won't come off with a 4" razorblade and a cup brush it's stuck to the hull pretty well!

 

 

 

 

  • Greenie 1
Link to comment
Share on other sites

3 minutes ago, TheBiscuits said:

First use one of these and about 3 packs of blades.  Start using it as soon as the hull is out of the water, still dripping.  Don't wait till the next day or even long enough to make a brew, get on with it immediately.

 

https://www.toolstation.com/prodec-advance-titan-heavy-duty-scraper/p75329

 

75329.jpg

 

Don't try and save a couple of quid on the cheaper handles, they are very uncomfortable to use for long periods and you have to faff with a screwdriver to change blades. DAMHIK ... 

 

After the first scrape, wash with a reasonable pressure washer - around 150 bar will do - then scrape again and wash again.

 

That'll get most (95%+) of the old bitumen off if you put enough effort in, although it's easier when it's soft and warm.

 

Then hit the hull with a whole box full of 75mm twisted strand cup brushes - steel not brass -  and a 4" angle grinder.  As soon as the brush starts getting clogged, fit another one.  Don't try and persevere with worn brushes or you'll not be correctly abrading the surface.  

 

That'll get nearly all the rest of the bitumen off. 

 

I tend to rope other people in to help, two or three extra bodies for a 60' boat means you can rest your arms occasionally!

 

It's seriously hard graft, but you'll be back to mostly bare steel by this point.  It's not Swedish Standard Sa2.5, I call it Swedish Chef standard (as done by a Muppet) but it's not fallen off yet.  

 

I use Hempel Hempadur 45143 with the cold climate curing agent - even in UK heatwaves it's the one to use.  The warm climate curing agent is for use much nearer the equator!

 

I'm on my second lot now, and I couldn't shift the first lot back to bare steel so figured if it won't come off with a 4" razorblade and a cup brush it's stuck to the hull pretty well!

 

 

 

 

Cheers bickies. 

 

Some great tips there. Thanks. I already do the scraping thing on bitumen it makes a huge difference. To a certain extent, I use a cup brush too, but generally only on the waterline. So none of this is foreign to us. 

 

 

Link to comment
Share on other sites

16 minutes ago, TheBiscuits said:

First use one of these and about 3 packs of blades.  Start using it as soon as the hull is out of the water, still dripping.  Don't wait till the next day or even long enough to make a brew, get on with it immediately.

 

https://www.toolstation.com/prodec-advance-titan-heavy-duty-scraper/p75329

 

75329.jpg

 

Don't try and save a couple of quid on the cheaper handles, they are very uncomfortable to use for long periods and you have to faff with a screwdriver to change blades. DAMHIK ... 

If you are going to use one of these, which is good, but a b@$+@£d of a job, make sure you get some padded gloves, no good knackering your palms on the first day meaning you cabt finish the job.

 

The other only slightly less effective tool to use in the same way is a sharpened garden hoe, far easier to wield over a large area.

Then pressure wash..

  • Greenie 1
Link to comment
Share on other sites

5 minutes ago, matty40s said:

If you are going to use one of these, which is good, but a b@$+@£d of a job, make sure you get some padded gloves, no good knackering your palms on the first day meaning you cabt finish the job.

 

The other only slightly less effective tool to use in the same way is a sharpened garden hoe, far easier to wield over a large area.

Then pressure wash..

Great idea. Can you get a carbide tipped garden hoe? 

 

A garden hoe is actually how I remove the barnacles from the bottom of our sail boat. Works a treat. 

Edited by rusty69
Link to comment
Share on other sites

13 minutes ago, rusty69 said:

Cheers bickies. 

 

Some great tips there. Thanks. I already do the scraping thing on bitumen it makes a huge difference. To a certain extent, I use a cup brush too, but generally only on the waterline. So none of this is foreign to us. 

 

 

Some years back at caggys in Tipton a guy there was using an old wood saw that had been shortened and the end ground down to form a 4inch scraper. The handle gave him a good grip to remove the loose bitumen.

20 minutes ago, matty40s said:

If you are going to use one of these, which is good, but a b@$+@£d of a job, make sure you get some padded gloves, no good knackering your palms on the first day meaning you cabt finish the job.

 

The other only slightly less effective tool to use in the same way is a sharpened garden hoe, far easier to wield over a large area.

Then pressure wash..

Sail makers glove maybe 🤣

  • Greenie 1
Link to comment
Share on other sites

41 minutes ago, matty40s said:

If you are going to use one of these, which is good, but a b@$+@£d of a job, make sure you get some padded gloves, no good knackering your palms on the first day meaning you cabt finish the job.

 

I reckon Rusty's palm callouses would be up to the job ... ;)

 

  • Haha 1
Link to comment
Share on other sites

10 hours ago, rusty69 said:

That's encouraging. Thanks. 

Do you recall what epoxy was used and how many coats? 

Matt at Northwich uses Dacrylate Epidac 2 pack, or he did last summer on our boat. Jet washed using a 4000psi machine, then 3 coats of epoxy 2 pack rollered on including the baseplate(optional).

 

First class service by Matt & Rebekah.

  • Greenie 2
Link to comment
Share on other sites

10 hours ago, Clanky said:

Matt at Northwich uses Dacrylate Epidac 2 pack, or he did last summer on our boat. Jet washed using a 4000psi machine, then 3 coats of epoxy 2 pack rollered on including the baseplate(optional).

 

First class service by Matt & Rebekah.

Thanks for that. 

 

I wonder if @Dacrylate Paints Ltd

Is the supplier of this stuff, and would care to comment please? 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.