Concrete Sink: Molds and Waterproof Materials Needed

Sounds like one of those 'simple' projects which you'll live to regret...or maybe you'll get eaten by an angry Lobster.
Sorry I have no good ideas on the subject...
Good luck
Del

Try 'Ferro-cement', using a wire armature starting with a mesh of #9 wire over a #3 re-bar frame, build up with hardware cloth and chicken wire. Use tie wire to compress the thicknesses to about 1/2" - 3/4" max. A fairly stiff sand mix, or prepackaged floor leveling mix is pressed in from both sides and polished with a spoon or similar tool. Keep it damp for as long as you can (at least a week or more). Installation will be aided by incorporating tabs or struts into the wire work.

Ferro-cement has been used for owner built sailing vessels, and is still used for barges and other watertight vessels. There is probably a wealth if info if you google it. I built a hot tub with it, and no further treatment was necessary to keep it waterproof. It polishes beautifully, and you can add some cement dye if you like.

Thank you. Anyway, the guy talked himself out of it and bought a stainless steel sink today. Thank God! No more joking suggestions. I can just drop it in anywhere in the wall. Whenever work slows down, I want to make a sunken water tank/pond in my back yard so the fero cement tip will come in useful. I am scared to use rebar in a pond. I have seen rusted rebar split concrete. I like the idea of hardware cloth though. It can be plastic. I have broken concrete that had plastic garden fence mesh in it and it was very very difficult to break. Anyway, I am still interested in the sink tech. I occasionally do garden ponds so any extra technical info is useful. Brian

I am scared to use rebar in a pond. I have seen rusted rebar split concrete.

You will find this very interesting...

Check out "Fine Homebuilding", there is an article on concrete countertops and sinks,(pay of course), but someone may have the magazine. There is also a book available for pouring concrete countertops. Rusty rebar is no problem, you can use hot dipped galvanized, or maybe try the poly shorts mixed in the concrete.

Hi vtbgiraud,

Good suggestions, but; "try the poly shorts mixed in the concrete." ?

You mean the ones with the hula girls printed on them? Or is that the concrete block coating with the fiberglass mixed in. It goes under various trade names like BlockBond, Dura..... whatever. Very good for a surface coating about 1/8" thick, but won't force through a wire armature.

I suspect the rusted re-bar had already started to rust before pouring with an inferior grade of concrete. Common with amateurs and "professionals" skimming/skimping on materials. Zinc chromate paint (nasty slime green) is used on all re-rod for bridge work nowadays. BTW: Iron filings can be added to concrete to increase resistance to hydraulic pressure. The rust fills the microscopic cavities.

Happy mud pies.

"This Old House" (TV show) did an episode where the homeowner went to a shop where they built her a one-piece concrete countertop and sink (built-in drainboards & all) during the show. They spelled out the mix in considerable detail, and the procedure was shown in sufficient detail that almost any handy person with access to the tools & equipment could replicate - should be a snap for a stonemason. By chance, that episode was re-run locally (Madison, WI channel 21) just yesterday evening. This seems to be the TOH Magazine variant of the story: http://www.thisoldhouse.com/toh/photos/0,,20050150,00.html

check these guys out...........i think there may be other competitors.....

http://www.concretenetwork.com/concrete/countertops/

How would a nice layer of epoxy paint applied over the finished (and properly cured) product work? It's durable, and I think it's waterproof as well. Your choice of colors.

Cheeries !