Blacking or epoxy coating?

[Cloudinspector]

Our newly acquired boat is overdue for blacking and I'm considering shelling out for epoxy coating.

I would like some feedback of the pros and cons of both methods.

Thanks

[bottle]

It will all get scraped off.

 

I am of the opinion that 'ordinary blacking' (there are many different types) is good enough, it does mean that your boat comes out of the water every two years and that means it can be inspected.

 

Welcome to the forum.

[KenK]

It will all get scraped off.

 

I am of the opinion that 'ordinary blacking' (there are many different types) is good enough, it does mean that your boat comes out of the water every two years and that means it can be inspected.

 

Welcome to the forum.

 

I'd agree, I can't see how an epoxy coating can be tough enough to survive an encounter with a bolt sticking out on a lock gate or a lump sticking out of a lock for example. At least with the ordinary stuff you can patch it easily.

 

Ken

[Chalky]

We've got epoxy applied to shot blasted steal. When lifted out after 4 years there was only 1 mark on it and the comments from the boat yard were along the lines that it could have been left a couple more years before it needed looking at. It seems to survive the usual stone / concrete impacts with no damage. I would certainly use it again. The expected life of the coating is over 5 years.

[NB Lola]

Timely debate

 

I considered the zinga option but was too much for my wallet.

 

The boat has blacking at present so we are bringing it out early October to check steel and decide. Once we have reviewed quality we will decide on treatment based on degradation since last it was out . I am keen to also see baseplate and understand extent of pitting, with some spot welding if needed. Just two years ago it had 8.4 integrity from 10 at the most pitted point.

 

Intwresting how well some boats fare re epoxy and if the price is right I would do that (bearing in mind shot blasting will need to be paid for) and lift her out annually anyway for a look at her nether regions.

[GSer]

I'm in a quandry myself, the same problem really I have two boats one epoxied, one blacked, at the moment i'm planning to shotblast the epoxied one then black it with standard blacking.

 

At least then I know i when I need to re-coat, at the moment it still needs to be lifted every few years to check it anyway, so I may as well black it then anyway.

 

Just thoughts at the moment, I had imagined that the blacking on the butty would wear long before the epoxy on Apache but the opposite is true so far IME.

[dor]

2-pack will last much longer than bitumen, but only if it doesn't suffer physical damage. Don't forget to add in the cost of sandblasting the hull as it needs to go on clean bare metal.

If you are on the Shroppie, the Shroppie shelf will cut through even epoxy when moored up (believe me - I have seen any number taken out of the water and 2-pack gets abraded as well).

As mentioned above, odd bolts etc sticking out of lock gates or piling will also cut through it. The danger here is that, because you think it is good for 5 or more years, the damage doesn't get seen and can be exposed and rusting for years. At least with ordinary blacking you will be having the boat out every two years. If you have to take the 2-packed boat out every two years to inspect it, as some people recommend, you are rather defeating the object of having 2-pack as the cost of slipping is a significant part of the cost of blacking.

[KenK]

2-pack will last much longer than bitumen, but only if it doesn't suffer physical damage. Don't forget to add in the cost of sandblasting the hull as it needs to go on clean bare metal.

If you are on the Shroppie, the Shroppie shelf will cut through even epoxy when moored up (believe me - I have seen any number taken out of the water and 2-pack gets abraded as well).

As mentioned above, odd bolts etc sticking out of lock gates or piling will also cut through it. The danger here is that, because you think it is good for 5 or more years, the damage doesn't get seen and can be exposed and rusting for years. At least with ordinary blacking you will be having the boat out every two years. If you have to take the 2-packed boat out every two years to inspect it, as some people recommend, you are rather defeating the object of having 2-pack as the cost of slipping is a significant part of the cost of blacking.

 

I'd second the Shropie bit, I assume that's why everyone seems to have Go Kart Tyres instead of standard fenders.

 

Ken

[CV32]

We have two pack on our boat - i have a few scars above the water line from this years trip to Birmingham and back (I attempted to steer rather than do all the locks, the OH did some of the locks as I used to get moaned at for having all the fun).

 

Went to a chandlers yesterday and enquired about two pack to touch up my steering indiscretions ... £178 for a five litre can

[nicknorman]

We have two pack on our boat - i have a few scars above the water line from this years trip to Birmingham and back (I attempted to steer rather than do all the locks, the OH did some of the locks as I used to get moaned at for having all the fun).

 

Went to a chandlers yesterday and enquired about two pack to touch up my steering indiscretions ... £178 for a five litre can

Ouch. We are having ours done in Sigmacover 300 2-pack bitumen. £42 for a 4 litre can doesn't seem too bad.

[Serenity Malc]

Yello,

 

That seems quite reasonable Nicknorman ....... is that a DIY price or what the yard are charging you per 4 litres to apply ?

 

Being a 2 pack ... does that mean breathing apparatus and a spray gun ?

 

Ta Malc.

[DHutch]

This topic comes round again and again, and you can look at past threads, but In my mind most 'standard black' (of which there is a great range) falls short of what I would paint onto my boat.

 

From new we used two pack system, blast primer, followed by epoxy aluminum, followed by epoxy blacking, and it has faired very well. In recent years following the advice of our supplier we have swapped to there single pot vinyl blacking (Leighs Resistex M535 www.leighspaints.com) and have found this to also be very good. We still use the two pack alu-epoxy to patch bare-metal areas, before applying two coats of blacking, every 4-5 years.

 

Typically the total bare area, contained to a very small isolated areas, is less than maybe 2sqft, on what it a very well used, all be it recreational, boat covering maybe around 30 days use a year.

 

I again, if you do a search there are a lot of past topics, several of which show photos of out boat on dock before and after blacking.

 

 

 

Daniel

 

This topic comes round again and again, and you can look at past threads, but In my mind most 'standard black' (of which there is a great range) falls short of what I would paint onto my boat.

 

From new we used two pack system, blast primer, followed by epoxy aluminum, followed by epoxy blacking, and it has faired very well. In recent years following the advice of our supplier we have swapped to there single pot vinyl blacking (Leighs Resistex M535 www.leighspaints.com) and have found this to also be very good. We still use the two pack alu-epoxy to patch bare-metal areas, before applying two coats of blacking, every 4-5 years.

 

Typically the total bare area, contained to a very small isolated areas, is less than maybe 2sqft, on what it a very well used, all be it recreational, boat covering maybe around 30 days use a year.

 

I again, if you do a search there are a lot of past topics, several of which show photos of out boat on dock before and after blacking.

 

 

 

Daniel

[steve hayes]

2 Pack epoxy.

Have had two boats done, the biggest advantage I can see is that the epoxy stops any pitting dead.

The only damage I can see after three years on Bluemoon (in the water, (up by Factory Locks on the BCN where the water is crystal clear is good for this)) is above the water line and caused by dodgy steelwork on locks and pillings has been sanded clean and touched up with standard paint.

 

Steve

[blackrose]

We are having ours done in Sigmacover 300 2-pack bitumen. £42 for a 4 litre can doesn't seem too bad.

 

I pressure washed a steam passenger boat last September which had been painted in Sigma pitch epoxy. After 10 years there wasn't a mark on the paint - we didn't even need to repaint it! However, the crew of these 100 year old boats make sure the hull doesn't touch lock sides, jetties or banks when they come in - fenders are always down. Canal boaters tend to bash their boats about a bit - sometimes it's unavoidable, but I still think a good two-pack paint will resist scratching far better than bitumen.

 

I don't know where this idea comes from that it's difficult to patch repair a two-packed boat? A little bit of prep with some abrasive paper of the correct grit size is all it takes (and you should be using the same product of course).

Edited September 5, 2012 by blackrose

[DHutch]

Indeed, I'm frequently surprised how much paint remains on our hull. I take the boat out with very mixed crew and we do our fair share of contacting immovable objects but it all most exclusivity appears to get taken up on the rubbing strakes leaving the blacking intact

 

Daniel

[ditchcrawler]

Ouch. We are having ours done in Sigmacover 300 2-pack bitumen. £42 for a 4 litre can doesn't seem too bad.

We use to use Sigma 2 pack when I worked Offshore. Hard as old nails. But it must be applied correctly, in the right conditions, to the correct thickness. Ours was done wIth airless spray with the operatives in full breathing gear and protective clothing.

[Timleech]

This topic comes round again and again, and you can look at past threads, but In my mind most 'standard black' (of which there is a great range) falls short of what I would paint onto my boat.

 

 

 

Daniel

 

Just to try to remove any potential confusion, 'Standard Black' is a trade name for a Coal Tar based paint/solution, used to be sold under the Wailes Dove 'Bitumastic' name but now under the Spencer Coatings umbrella.

 

I'm curious as to why your suppliers recommended a change to a 1-pack vinyl (presume similar to Comastic?)? I don't think Leighs do a 2-pack tar paint currently, was your original coating from Leighs?

 

Tim

Edited September 5, 2012 by Timleech

[nicknorman]

Yello,

 

That seems quite reasonable Nicknorman ....... is that a DIY price or what the yard are charging you per 4 litres to apply ?

 

Being a 2 pack ... does that mean breathing apparatus and a spray gun ?

 

Ta Malc.

No, we chose black. That is the price for a tin to take away for touchups. The yard charges £11/ft for bitumen, £12/ft for intertuff, £12.50/ft for Comastic and £15/ft for Sigmacover 300. I am not sure how they apply it but I think it is brushed / rollered on. Of course the additional cost arises because you need to apply it to bare steel, so grit blasting is required the first time. I think for subsequent applications grit blasting is not required - it would be much the same job as applying normal blacking.

 

We are picking the boat up on Saturday morning so it will be interesting to see how it looks.

Edited September 5, 2012 by nicknorman

[Timleech]

No, we chose black. That is the price for a tin to take away for touchups. The yard charges £11/ft for bitumen, £12/ft for intertuff, £12.50/ft for Comastic and £15/ft for Sigmacover 300. I am not sure how they apply it but I think it is brushed / rollered on. Of course the additional cost arises because you need to apply it to bare steel, so grit blasting is required the first time. I think for subsequent applications grit blasting is not required - it would be much the same job as applying normal blacking.

 

 

If recoating 'old' 2-pack, it needs to be abraded first. Even then, my limited experience tells me it doesn't adhere nearly as well as the original coating. I suppose that's not desperately important where the original coating is sound, though.

 

Tim

[nicknorman]

We use to use Sigma 2 pack when I worked Offshore. Hard as old nails. But it must be applied correctly, in the right conditions, to the correct thickness. Ours was done wIth airless spray with the operatives in full breathing gear and protective clothing.

Perhaps worth mentioning that there are lots of different Sigmacover products optimised for different applications. 300 seems to be the one for inland boats. though it is perfectly OK in salt water or water contaminated with diesel / oil

[ditchcrawler]

Anyway, if using two pack, why black?

[blackrose]

Anyway, if using two pack, why black?

 

No reason at all, apart from people wanting traditional looking coatings.

 

Some barges I've seen have red paint up to the waterline. Looks good. I assume it's a two-pack of some description.

Edited September 5, 2012 by blackrose

[RLWP]

No reason at all, apart from people wanting traditional looking coatings.

 

Some barges I've seen have red paint up to the waterline. Looks good. I assume it's a two-pack of some description.

 

Not just barges

 

 

Actually, it's a look I quite like on certain kinds of boat. It's something I would certainly consider for a steam launch

 

Richard

Edited September 5, 2012 by RLWP

[DHutch]

I'm curious as to why your suppliers recommended a change to a 1-pack vinyl (presume similar to Comastic?)? I don't think Leighs do a 2-pack tar paint currently, was your original coating from Leighs?

It was, at which point, I think you have answered your own question!

- I've only ever used what we use, so cant really compare it to comastic, but im sure its not unique.

- Its fairly thick, skins rapidly and dries shortly after, goes really fairly hard, washes out with xylene or just chuck the roller.

 

 

Daniel

[Ally]

We have 2 pack on ours from when it was built...about 7-8 years ago. Checked it when we pulled out early this summer and it was still perfect. Admittedly it had done no miles till we got it 3 years ago. The other advantage I see with it is it doesn't suffer from diesel disolving it at the waterline if you are in a marina where there are diesel spills....as there always seemed to be near our mooring, and the ice didn't bother it either.