Water Tank Painting

[Tracy D'arth]

10 minutes ago, Opener said:

OK - two coats of Rylard stuff drying/curing in built in steel tank. I've read the data sheet but has anyone practical experience of the process of flushing/cleaning out ready for fresh water? It's a big tank and running the pump to empty it once, never mind three times will take for ever. Contemplating Milton or detergent or camping water purifier. Might just have to bale the tank to speed emptying. What say you?

I have never bothered filling and draining, just use the water as normal till the tank is empty, refill and then you can drink the water straight from the tank.

I can't detect any taint if its allowed to dry properly for a week or so.

TD'

[Chewbacka]

I filled mine before fixing the lid on, left for a day then emptied with a 240v sump pump I had - it was clean & disinfected - took longer to fill than to empty.

[blackrose]

On 12/07/2020 at 10:34, Tracy D'arth said:

 Properly done a bitumened steel tank will last for years before it needs doing again. I know of many that were done by me over 10 years ago and they are still OK.

 

Bitumen that lasts 10 years exposed to water? That must be some super-bitumen that nobody else here has ever heard of... ?

 

Depends what you mean by "ok after 10 years" I suppose. It might look ok visually but if water gets behind any area of paint and starts corroding the steel then it may as well have got behind the whole lot and that's not ok in my book. The rate of corrosion will be no different, it will just be over a smaller area.

Edited July 15, 2020 by blackrose

[Tracy D'arth]

13 minutes ago, blackrose said:

 

Bitumen that lasts 10 years exposed to water? That must be some super-bitumen that nobody else here has ever heard of... ?

 

Depends what you mean by "ok after 10 years" I suppose. It might look ok visually but if water gets behind any area of paint and starts corroding the steel then it may as well have got behind the whole lot and that's not ok in my book. The rate of corrosion will be no different, it will just be over a smaller area.

OK call me a liar then.

 

I do did  the job properly. 

[Sea Dog]

20 hours ago, blackrose said:

Bitumen that lasts 10 years exposed to water? That must be some super-bitumen that nobody else here has ever heard of... ?

Inside a fresh water tank is hardly the harshest of environments though, is it.

[MrsM]

Just about to start this job (our first) on our recently purchased boat. Happy with the process of painting but what do we do about the pipe that takes water out of the tank into the boat? Presumably this is mild steel too and will therefore rust? How do we clean and coat the inside of this pipe to prevent deterioration? It isn't straight so not easy to pull something through. How do you usually deal with this part of the system? TIA

[Tracy D'arth]

1 minute ago, MrsM said:

Just about to start this job (our first) on our recently purchased boat. Happy with the process of painting but what do we do about the pipe that takes water out of the tank into the boat? Presumably this is mild steel too and will therefore rust? How do we clean and coat the inside of this pipe to prevent deterioration? It isn't straight so not easy to pull something through. How do you usually deal with this part of the system? TIA

Replace if in doubt. Wire brush pull through? String through the pipe, fill end with bitumen, tie a bit of rag onto the string, drag it back through pulling bitumen in.

Or if its a decent bore size. line it with 15mm plastic tarred in both ends with bitumen.

TD'

[Tony Brooks]

1 minute ago, MrsM said:

Just about to start this job (our first) on our recently purchased boat. Happy with the process of painting but what do we do about the pipe that takes water out of the tank into the boat? Presumably this is mild steel too and will therefore rust? How do we clean and coat the inside of this pipe to prevent deterioration? It isn't straight so not easy to pull something through. How do you usually deal with this part of the system? TIA

 

Without seeing I can't say. It could be copper. There may be a threaded  nipple welded onto the tank to accept a threaded fitting. The pipe or whatever might have been galvanised but any welding would have destroyed that.

 

I suspect most people just do the best they can. As water will always be passing through that pipe I doubt any rust will build up in it enough to taint the water, unlike in the tank

[Tracy D'arth]

3 minutes ago, Tony Brooks said:

 

Without seeing I can't say. It could be copper. There may be a threaded  nipple welded onto the tank to accept a threaded fitting. The pipe or whatever might have been galvanised but any welding would have destroyed that.

 

I suspect most people just do the best they can. As water will always be passing through that pipe I doubt any rust will build up in it enough to taint the water, unlike in the tank

I bought a boat with water under the floor, reckon the owner thought it was holed.

I knew it was fresh water, taste test.  Turned out to be the 1/2" iron coupler that was welded to the tank wall before the stop tap rusted through.

I blanked the tank off inside with a rubber washer and through bolt. Drilled tank and fitted a plastic H2O tank connector, pipe to stop valve. Job done.

[MrsM]

Thank you both. Will explore further when we get the tank emptied and start the cleaning process. You guys are so helpful ☺️

[Opener]

3 hours ago, MrsM said:

Just about to start this job (our first) on our recently purchased boat. Happy with the process of painting but what do we do about the pipe that takes water out of the tank into the boat? Presumably this is mild steel too and will therefore rust? How do we clean and coat the inside of this pipe to prevent deterioration? It isn't straight so not easy to pull something through. How do you usually deal with this part of the system? TIA

Watch London Boat Girl video on YouTube - the hazards of the pick-up pipe.  Having watched this I was prepared for trouble.  If your tank is lined with rust, weird looking growths and cr@p, then the pick-up toob is likely to be as well.  Carefully inspect the interior - yeah!, good luck with that!!

I managed to remove the threaded stop tap from the outside of the tank (once the tank was emptied!!!) inside the cabin.  Thus I had clear access to both ends.  Pushed a length of curtain wire through the pipe.  {Curtain wire is also your friend for unblocking kitchen and bathroom sink outlet).  Stripped plastic off end of curtain wire and worked it in and out until it would pass freely.  Then try to uncoil the far end so that you have a vicious pointed hook.  Reduce to a practical length and insert other end in an electric drill.  The nasty pointy end plus the flexibility of the wire as it threshes around down the pipe should clear at least a useful size of hole.  Keep at it until you feel happy with how freely it pushes in and out.  (I actually found a similar 'drain unblocker' in a hardware shop which actually uses the same principal but is probably no more effective).

My boat had survived 15+ years without the toob blocking so form your own judgement as to whether internal blacking is actually required.  I haven't done as suggested above but, if you can manage it, it sounds like a good idea.

[MrsM]

9 hours ago, Opener said:

Watch London Boat Girl video on YouTube - the hazards of the pick-up pipe.  Having watched this I was prepared for trouble.  If your tank is lined with rust, weird looking growths and cr@p, then the pick-up toob is likely to be as well.  Carefully inspect the interior - yeah!, good luck with that!!

I managed to remove the threaded stop tap from the outside of the tank (once the tank was emptied!!!) inside the cabin.  Thus I had clear access to both ends.  Pushed a length of curtain wire through the pipe.  {Curtain wire is also your friend for unblocking kitchen and bathroom sink outlet).  Stripped plastic off end of curtain wire and worked it in and out until it would pass freely.  Then try to uncoil the far end so that you have a vicious pointed hook.  Reduce to a practical length and insert other end in an electric drill.  The nasty pointy end plus the flexibility of the wire as it threshes around down the pipe should clear at least a useful size of hole.  Keep at it until you feel happy with how freely it pushes in and out.  (I actually found a similar 'drain unblocker' in a hardware shop which actually uses the same principal but is probably no more effective).

My boat had survived 15+ years without the toob blocking so form your own judgement as to whether internal blacking is actually required.  I haven't done as suggested above but, if you can manage it, it sounds like a good idea.

Thanks Opener, that sounds like a practical method and I will give it a go, after watching the video first! If possible I would like to replace the pick up tube with copper or plastic so that I know I'm starting off with something clean. Our tube isn't blocked as we get water on board, but given the state of the tank I expect it is lined with all manner of nasties! ? Happy days! I've got a flexible plastic sink unblocker from Lakeland that I use for cleaning bath/shower plugs and traps so I'll see if that will do the job but I expect it will be too wide. 

https://www.lakeland.co.uk/23725/The-Drain-Weasel-2-Disposable-Plughole-Cleaning-Brushes

[Opener]

You've seen the inside of your tank.  That is what the inside of your pick-up tube is going to be like but probably to a lesser degree because of the constant flow of water.  Your 'Lakeland' will be fine on soap and hair (if I read that right) but the crud up your pipe will be in a different league.  Be prepared to be a bit more brutal. [IIRC LBG video is more about the problem than about the solution].  A few regular Boat Tubers have posted about the process of doing a tank - worth a look just for their solutions/problems/experiences/timings.  Good luck?.

[Tony Brooks]

27 minutes ago, MrsM said:

Thanks Opener, that sounds like a practical method and I will give it a go, after watching the video first! If possible I would like to replace the pick up tube with copper or plastic so that I know I'm starting off with something clean. Our tube isn't blocked as we get water on board, but given the state of the tank I expect it is lined with all manner of nasties! ? Happy days! I've got a flexible plastic sink unblocker from Lakeland that I use for cleaning bath/shower plugs and traps so I'll see if that will do the job but I expect it will be too wide. 

https://www.lakeland.co.uk/23725/The-Drain-Weasel-2-Disposable-Plughole-Cleaning-Brushes

I doubt there are many nasties in the tank unless it has stood unused for a year or more. As it seems to be a mild steel tank it will be covered in rust and the water may well take on a rusty hue after filling or after a hard bump but that is cosmetic, not nasty.

 

If you want to get rid of any nasties drain the tank, pour in a full  bottle of cheap unperfumed and runny bleach & refill. Run the taps until you can smell the bleach, leave several hours or overnight. Drain and refill with fresh water, flush the pipes via the taps. You will have a bleachy taint for a while but there should be no nasties left in the system.

[Tracy D'arth]

Pity they stopped child chimney sweeps, ideal for this job. Ah, progress. Its all some modern kids are fit for. Pull throughs for cannon comes to mind.

TD'

[ditchcrawler]

I don't see how you could replace this so called pickup tube with plastic or copper as its likely to be a welded spigot in the side of the tank with hopefully a gate  or ball valved screwed on it, 2" long at the most. The only way I can see is to do what Tracy suggested, chopping it off and blanking followed by drilling another hole and fitting a tank flange.

This to my mind  would be a backward step if the old spigit is still serviceable as you are introducing 2 more possible leak points, your patch and the flange

[Machpoint005]

On 03/07/2020 at 20:58, Opener said:

>>Try Boat Paint for Rylard water tank coating - excellent service. <<

 

Seconded. Ordered mine on Thursday evening, delivered this afternoon (Monday) by DHL: well done Boatpaint Ltd.

 

Each tin has a very comforting label in large capital letters: WATER TANK PAINT.

 

 

 

[Opener]

Final episode: tank blacking (Rylard) nice and hard after 10 days in enclosed cratch with tank lid off.

Sprayed inside with detergent and sponged down vigorously. Hosed off suds and pumped/dried down.

Refilled with water ? - used mainly for washing/toilet but now using for drinks - not foaming at the mouth yet.

Keep checking pump filter throughout this process - some bits are bound to get filtered out no matter how careful you are.

[Tracy D'arth]

1 hour ago, Opener said:

Final episode: tank blacking (Rylard) nice and hard after 10 days in enclosed cratch with tank lid off.

Sprayed inside with detergent and sponged down vigorously. Hosed off suds and pumped/dried down.

Refilled with water ? - used mainly for washing/toilet but now using for drinks - not foaming at the mouth yet.

Keep checking pump filter throughout this process - some bits are bound to get filtered out no matter how careful you are.

Well done. said it was easy!?

TD'

[blackrose]

On 16/07/2020 at 16:23, Sea Dog said:

Inside a fresh water tank is hardly the harshest of environments though, is it.

Harsh enough to need repainting long before it's 10 years old. I think that's most people's experience of painting tanks with bitumen.

On 15/07/2020 at 20:28, Tracy D'arth said:

OK call me a liar then.

 

I do did  the job properly. 

 

I didn't call your a liar, calm down dear!

 

People have different ideas of what constitutes a proper job and when a job needs re-doing, that's all.

Edited July 25, 2020 by blackrose

[Tracy D'arth]

34 minutes ago, blackrose said:

Harsh enough to need repainting long before it's 10 years old. I think that's most people's experience of painting tanks with bitumen.

 

I didn't call your a liar, calm down dear!

 

People have different ideas of what constitutes a proper job and when a job needs re-doing, that's all.

Just woken up chuck?

TD'

[Machpoint005]

22 hours ago, Opener said:

Final episode: tank blacking (Rylard) nice and hard after 10 days in enclosed cratch with tank lid off.

Sprayed inside with detergent and sponged down vigorously. Hosed off suds and pumped/dried down.

Refilled with water ? - used mainly for washing/toilet but now using for drinks - not foaming at the mouth yet.

Keep checking pump filter throughout this process - some bits are bound to get filtered out no matter how careful you are.

 

Thanks for the pointer - I hadn't though of that method.

First coat of Rylard applied today, so let's have some warm weather and the second coat will go on next weekend.

 

 

 

 

[WillCful]

Ooooh an opportune thread! I will be de-rusting my water tank in the next few weeks. I've already done the interior of the hull, went for the angle grinder method followed by epoxy primer, it's fine just messy! Protective gear is a must. I'll be doing the same in the water tank, I've found you need a drill attachment or hand wire brush as well to get right into the corners.

 

My pick up tube was full of rusty stuff, it's just a mild steel pipe welded into the tank. It took a good prodding with a flat head screwdriver to get all of it out, then I'll clean and epoxy inside it. Considering fitting a plastic fitting though (speedfit 22mm tank connector), I guess it's another potential failure point but it'll stay clean and might be easier for maintenance in the future... guess it depends how well you block off the old one! I'm thinking some kind of rubber bung on the inside and then cap it off on the outside, it's got a 3/4 thread on the 'outside' end.

 

Super satisfying work though, it looks so good when it's done! A neighbouring boater suggested today that I should buy a light colour of epoxy (not black) so that it's easier to see inside the tank in the future... ? A good thought but I guess it depends on what colours you can buy the potable epoxy in, hopefully they do rainbow...

[Machpoint005]

Choose an old pair of shoes, use them whenever you are inside the tank.  Once the job is completely finished, throw them away.

 

I notice you're using epoxy, but I suspect the following remarks may still be somewhat relevant. I'm using Rylard, for which the solvent (brush cleaner) is no.3 thinners. Have you seen the price of that stuff? I've adopted a "disposable brush and roller" approach - cheaper than a litre of thinners and a lot less trouble!

 

 

 

 

[Tracy D'arth]

19 hours ago, WillCful said:

A neighbouring boater suggested today that I should buy a light colour of epoxy (not black) so that it's easier to see inside the tank in the future... ? A good thought but I guess it depends on what colours you can buy the potable epoxy in, hopefully they do rainbow...

A good thought, blue would be appropriate, perhaps not green!

TD'

 

 

Edited July 27, 2020 by Tracy D'arth