Painting Inside A Water Tank

[echnidna]

Painting Inside A Drinking Water Tank
I've scrounged a couple of tanks that are mechanically sound.
I would like to paint inside them, would expoxy resin be suitable instead of paint?

[Steve Fryar]

Beleive me this works.Mix up powdered milk with cement and mix with water till you get a consistency where you can apply with a brush.My grandfather was a tank maker and repaired many with this method.It will add years to the life of your tank.
Cheers, Steve.

[elmoticus]

I agree, have used the cement and water trick in the past on the inside of a concrete tank.

[rotten_66]

Please be careful.
:o

Using epoxy resin in a confined space can be fatal, fumes build up and often before you know it "game over". Use breathing apparatus, have a rope system set up and have a buddy outside watching everything you do. Anything goes wrong they can pull you out, but not climb in themselves.

[RETIRED]

What sort of tanks?

[joe greiner]

I have almost no idea what the powdered milk adds to the recipe; maybe to stiffen the mix. The cement sounds good to me. If you've scrounged the tanks, they must be light enough to lay down for easier escape, but be careful anyway.

I've designed several water tanks for drinking water - all concrete, and up to 20 million gallons (about the size of a football stadium). I don't recall any of them needing additional cement coating, initially. But I'm not a plumber.:rolleyes:

Joe

[Skew ChiDAMN!!]

Cement by itself is very brittle. I could understand if a powdery sand was added as the aggregate, but powdered milk?

I can see that the next time I'm out on-site I'm gonna get empirical on this one. If it works, it'd be a really handy little trick for all sorts of things. :D

[joe greiner]

The powdered milk might make it more of a gel than a slurry, thus reducing brittleness. Just a guess, of course.

Joe

[ian]

Cement by itself is very brittle. I could understand if a powdery sand was added as the aggregate, but powdered milk?

I can see that the next time I'm out on-site I'm gonna get empirical on this one. If it works, it'd be a really handy little trick for all sorts of things. :Dpowered milk contains cassen (spelling?) aka animal glue would help the cement bond to tank walls — think of how bondcrete is used


ian

[echnidna]

its a plastic tank so cement won't stick.

dunno what sort of plastic but the outside has a 5/6mm thick fibregalss skin so epoxy should stick to the inside.

[Steve Fryar]

Oops sorry.I thought it was corrugated iron.The powdered milk with the cement acts as a bonding agent.It sticks to galv like you know what to a blanket.

[Skew ChiDAMN!!]

Thanks Ian, Steve.

I'm still going to try it out... although I must admit not on gal. Like Bob, we've a plastic 400L tank on site that leaks. It has a micro-fracture in the base, which is OK until the tank is about 1/3 full and then it starts weeping. Becoming worse as the tank fills, of course.

I've been meaning to try a hot soldering iron on the inside, but being only 400L it's a small, cramped space and who really wants to breathe hot plastic vapours? I think I'll try the conc/powdered milk trick first. :2tsup:

As the tank will be a throwaway if I can't fix it and I can't stand powdered milk, what have I got to lose? :D

[wheelinround]

Echnidna try plastic welding it o find someone who does it

[echnidna]

its mechanically sound but was used for storing detergent so I want to apply a safe sealer coat inside.

[Skew ChiDAMN!!]

I can't see why Epoxy wouldn't work...

Perhaps wash it out with a dilute caustic solution first, to help the epoxy to key in? Hmmm... maybe not.

[Master Splinter]

If it was just used for detergent, pressure wash it. Normal detergent isn't the most toxic of substances and you'd get more of a detergent dose from a glass you didn't rinse properly.

I'd be much more worried about leftover compounds from the epoxy. (WEST don't recommend theirs for lining vessels used to store drinking water).

[ian]

its mechanically sound but was used for storing detergent so I want to apply a safe sealer coat inside.Bob
If you can get the tank clean enough that the coating will adhere to the sides, I can't see any valid reason to apply any coating

But if you insist
Don't use epoxy — the fumes confined inside the tank will probably kill you
I'd be similarly concerned with oils based paints

look at one of the latex waterproofing paints



ian

[echnidna]

If it was just used for detergent, pressure wash it. Normal detergent isn't the most toxic of substances and you'd get more of a detergent dose from a glass you didn't rinse properly.

I'd be much more worried about leftover compounds from the epoxy. (WEST don't recommend theirs for lining vessels used to store drinking water).

It was hospital detergent. Don't know what.

I was thinking wests epoxy as its a lot cheaper than bitumeous,
thanks for that MS, looks like its hydroseal for the job.