fresh water tank paint

[Guest]

Morning all,

Sorry if this has been covered before but I can't find any links.

We've been getting brown 'bits' through our water system, looks like very fine rust. So decided to drain tank clean and paint the inside which I understand is OK however, what special paint have folks used? What's the best way to do it etc etc. When completed will be fitting a filter, not sure which one yet. Many thanks

[Guest]

Hi further to my above post, I've managed to find an old link. 2006, very interesting reading think I won't go through the hassle of painting. Although our boat is 1991 initially there was a lot of brown water but since we have lived on for past three years, we always flush through the hose before use, regularly fill the tank, so there is always clean water in the tank. Will use tablets then get an inline filter. Cheers

[Sea Dog]

Hi further to my above post, I've managed to find an old link. 2006, very interesting reading think I won't go through the hassle of painting. Although our boat is 1991 initially there was a lot of brown water but since we have lived on for past three years, we always flush through the hose before use, regularly fill the tank, so there is always clean water in the tank. Will use tablets then get an inline filter. Cheers

I'd be interested to know what thread it was that persuaded you to change your mind.

[frangar]

Hi further to my above post, I've managed to find an old link. 2006, very interesting reading think I won't go through the hassle of painting. Although our boat is 1991 initially there was a lot of brown water but since we have lived on for past three years, we always flush through the hose before use, regularly fill the tank, so there is always clean water in the tank. Will use tablets then get an inline filter. Cheers

Would you also not ever bothering blacking your hull?.....the only difference is that it will rust from the inside out!

 

Whilst it's now slightly frowned on myself and many others use a simple bitumen paint inside the tank.....The Blackjack brand used to be potable water approved but this has been changed recently due to changes in legislation....however ive suffered no ill effects over the last 20 odd years

 

Cheers

 

Gareth

[dmr]

We did out tank a couple of years ago, before that it had not been done for at least several years (5-10). It was mostly in very good condition but in a couple of places the blacking had perforated and there were surprisingly deep pits (1.5-2mm) in the baseplate. Our water was still totally clear so your tank might be in worse condition than ours.

 

Best approach is to take it back to bare meta, or very nearly bare metal, and paint it in the epoxy from "Reactive Resins". Not a nice or easy job, I copped out and paid a brave gentleman to do it for me.

 

...............Dave

[IDS]

You can't paint tank insides at this time of year anyway, you need to wait for summer weather to avoid condensation forming as you try to paint. The upside of this is it gives you plenty of time to plan, and possibly even to drain and open the tank to give it an inspection and gauge the extent of the task ahead. My boat is a couple of years older than yours and it definitely needed to be done, although the rust silt stayed firmly in the base of the tank and never found its way out of the taps (due to internal configuration of tank). Depending on your tank configuration it is not a job many relish, but if you do it yourself at least you know it is done properly. If you have the cash get a boatyard to do it.

[blackrose]

I agree with Iain Duncan Smith above. It's a difficult job to do properly and needs planning especially if you use the Reactive Resins or other water potable epoxy systems, as these paints have min/max overcoating times. If you live aboard the first part of the plan should be to connect a garden water butt to your pump while your tank is out of action.

Edited October 30, 2016 by blackrose

[Horace42]

I fixed my water tank by fitting a plastic liner. A bit fiddly connecting the plastic outlet to the boat pipe through the

bulkhead, and connecting the plastic filler pipe to the boat deck.

But it worked a treat.But I also had some minor leaking rust holes appearing in the bulhead that had to be fixed

(caused by vigorous scraping away at rusty patches to get back to bare metal prior to painting).

Edited October 29, 2016 by Horace42

[tonyt40]

There's a bit here about water tanks and cleaning your water system.

 

http://www.canalworld.net/forums/index.php?showtopic=87493&hl=

[Capt Ahab]

Would you also not ever bothering blacking your hull?.....the only difference is that it will rust from the inside out!

 

Whilst it's now slightly frowned on myself and many others use a simple bitumen paint inside the tank.....The Blackjack brand used to be potable water approved but this has been changed recently due to changes in legislation....however ive suffered no ill effects over the last 20 odd years

 

Cheers

 

Gareth

I had an interesting explanation offered when I bought a tin of Blackjack potable bitumen recently. It appears that the factory where it is made burned down and production moved to a new site. The new site has yet to be certified for water tank use, but its the same product as before. Having stripped back the water tank a few times now I am surprised how the surface deteriorates and I cringe at the thought of drinking from a tank with so much rust (even though it looks fine). I will now strip it back and reapply two thick coats every three years and have also added a water filter.

[tonyt40]

I really can't get my head round why people are still painting there water tanks with bitumen when there are much better (and approved for potable water) products on the market. Would you paint your mugs and glasses with bitumen and still drink from them?

 

Bitumen based products are outlawed for use in water systems by the Water Regulations advisory scheme (WRAS) and other organisations.

Edited October 29, 2016 by tonyt40

[blackrose]

I fixed my water tank by fitting a plastic liner. A bit fiddly connecting the plastic outlet to the boat pipe through the

bulkhead, and connecting the plastic filler pipe to the boat deck.

But it worked a treat.But I also had some minor leaking rust holes appearing in the bulhead that had to be fixed

(caused by vigorous scraping away at rusty patches to get back to bare metal prior to painting).

If the OP wants to fit a tank liner they should also be aware that they will need to insulate the tank with something like carpet tiles prior to fitting it. I went through this issue very thoroughly with Duratank/HCL one of the main suppliers. If you don't insulate the tank you may get a build up of condensation between the tank and the liner (full of cold water) which could allow corrosion to continue behind the liner. Any protruding edges such as the steel supports on the underside of the well deck also need be covered with something like pipe insulation so that they don't chafe the liner as it expands during repeated fillings.

 

So when you say it's fiddly I would say it's also a fair amount of work to prep, paint and then insulate the tank prior to installing the liner. Personally I took the view that I'd rather just thoroughly prep and then paint the tank with 4 coats of epoxy. That may not last the estimated 15 years lifespan of the tank liner stated by Duratank, but then it didn't cost the best part of a grand - quoted for a liner for my boat. I think it's probably about 500 quid + vat for a narrowboat depending on size and design.

Edited October 30, 2016 by blackrose

[Horace42]

If the OP wants to fit a tank liner they should also be aware that they will need to insulate the tank with something like carpet tiles prior to fitting it. I went through this issue very thoroughly with Duratank/HCL one of the main suppliers. If you don't insulate the tank you may get a build up of condensation between the tank and the liner (full of cold water) which could allow corrosion to continue behind the liner. Any protruding edges such as the steel supports on the underside of the well deck also need be covered with something like pipe insulation so that they don't chafe the liner as it expands during repeated fillings.

 

So when you say it's fiddly I would say it's also a fair amount of work to prep, paint and then insulate the tank prior to installing the liner. Personally I took the view that I'd rather just thoroughly prep and then paint the tank with 4 coats of epoxy. That may not last the estimated 15 years lifespan of the tank liner stated by Duratank, but then it didn't cost the best part of a grand - quoted for a liner for my boat. I think it's probably about 500 quid + vat for a narrowboat depending on size and design.

You have stirred up some distant memories and I vaguely recall going through a similar exercise. Because of the rust and leaking bulkhead I went for the plastic tank. Cant remember the make, but HCL Clicks. (somewhere down Portsmouth way).

It looks like my 15 years is up. That was a useful tip. Thanks

[Neil2]

I'm glad someone raised this, I've been dithering for three years now about what to do with my integral tank. I was pretty much sold on the plastic liner then I met one owner recently that had a duratank made and fitted and he said the same as Blackrose. You still have to treat the inside of the tank because there is the condensation issue. I guess you could make a sort of suspended platform for the tank to sit on? I believe you also have to allow air to get in and out of the void because of the expansion/contraction of the tank?

[Chewbacka]

I'm glad someone raised this, I've been dithering for three years now about what to do with my integral tank. I was pretty much sold on the plastic liner then I met one owner recently that had a duratank made and fitted and he said the same as Blackrose. You still have to treat the inside of the tank because there is the condensation issue. I guess you could make a sort of suspended platform for the tank to sit on? I believe you also have to allow air to get in and out of the void because of the expansion/contraction of the tank?

Unless there is something very wrong with it, what is wrong with cleaning it out and repainting?

[Neil2]

Unless there is something very wrong with it, what is wrong with cleaning it out and repainting?

 

If/when I have to go down there to clean it out I do not want to have to do it again. Also I don't trust integral tanks for drinking water.

[The Hunky Dory]

We've an integral tank, which was painted with Epicol solvent free blue two pack plastic paint when the boat was built. Its a bit like the stuff you see in swimming pools. After 10 years I repainted it, although it was generally still sound, just a bit of cracking where I bumped the bows. Its very expensive at £100 for 2.5 litres which does 2 coats. Obtainable from Mainline paints in Liverpool. Suitable for drinking water, although we also have a filter.

[blackrose]

We've an integral tank, which was painted with Epicol solvent free blue two pack plastic paint when the boat was built. Its a bit like the stuff you see in swimming pools. After 10 years I repainted it, although it was generally still sound, just a bit of cracking where I bumped the bows. Its very expensive at £100 for 2.5 litres which does 2 coats. Obtainable from Mainline paints in Liverpool. Suitable for drinking water, although we also have a filter.

It sounds similar to the Armourguard water based, water potable epoxy. I put 2 coats on over 2 coats of non water potable epoxy. I should have given the Armourguard stuff another coat but I ran out. I plan to have a look in 5 or 6 years and if necessary get back in there, key up the surface and apply another few coats.

[Neil2]

I'd be happy with something like Epicol but with a 30 year old tank I think I'd struggle to get the steel clean enough now.

 

This thread has made me think though, and I'm now considering cutting away the front well deck completely and reducing the size of the tank with a new bulkhead so I can create a bit more dry storage. The tank is way too big for the boat, holds well over a tonne I reckon.

 

If I expose the inside of the tank to this extent I guess I could get it blasted or maybe even a scabbler/needle gun would do as a prep for epoxy coating.

 

Might even be cheaper than a liner or a s/s tank.

[blackrose]

You can do it with wire wheels on a mini angle grinder but it's a horrible job that most boaters wouldn't want to undertake. I did it that way in the rusty bilges of a 113 year old steam boat so your 30 year old boat should be fine. Depends how much time you have, but if you just do a bit each day you'll get there.

 

On my tank I worked over weekends and during the week I put some moisture absorber in there in a plastic container to prevent any flash rust and sealed the hatch with a bin liner and some silicone to stop any rain getting in.

 

Don't neglect to wear your PPE if you use wire wheels. Get yourself a decent dust mask, eye protection and ear defenders. I asked about blasting but was told he wouldn't be able to get in through the hatch with all his gear.

Edited November 5, 2016 by blackrose

[bigcol]

wouldnt it be nice if you could place a can of paint,blackjack what ever close the tank and activate!!

 

What was done to a previous boat, integral tank, top was cut of to slow access, we bought a mobile thick hard plastic water tank

The type mobile valeting vans have in their vans.

Has holes already for pipe fitting and breather hole.fraction of the cost job done.

 

Col

[bigcol]

http://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2060353.m570.l1313.TR3.TRC2.A0.H0.Xvaleting+water+tank.TRS0&_nkw=valeting+water+tank&_sacat=0

 

You can get different sizes

shapes and small to large tanks 1000 ltr tank.

[Neil2]

You can do it with wire wheels on a mini angle grinder but it's a horrible job that most boaters wouldn't want to undertake. I did it that way in the rusty bilges of a 113 year old steam boat so your 30 year old boat should be fine. Depends how much time you have, but if you just do a bit each day you'll get there.

 

On my tank I worked over weekends and during the week I put some moisture absorber in there in a plastic container to prevent any flash rust and sealed the hatch with a bin liner and some silicone to stop any rain getting in.

 

Don't neglect to wear your PPE if you use wire wheels. Get yourself a decent dust mask, eye protection and ear defenders. I asked about blasting but was told he wouldn't be able to get in through the hatch with all his gear.

 

When we had the hull galvanised it obviously had to be blasted back to bare metal and I asked them about doing the inside of the water tank, they said the same, it's not possible just through the hatch. It was their suggestion that we cut the entire front well deck away to fully expose the tank below but there just wasn't time within the slot we had booked to get it done. Debdale also flat refused to attempt cleaning the inside of the tank through the hatch, Mike Goode said he wouldn't ask any of his staff to do such an unpleasant job, though I think he said he might persuade his student son to do it as he was desperate for money..