Making a large hole as in the above 2 sink options greatly increases the overall weakness of the concrete piece and stress cracks are common around sinks.
Pouring a concrete sink.
The concrete forms are made of 3 4 melamine boards.
On the table saw rip four strips of melamine 2 1 4 wide and long.
Consider concrete tool rental for your big project.
Install as apron front or standard undermount.
Cut one piece of melamine the same size as the finished countertop.
Melamine is readily available at home centers and lumber yards has smooth surfaces that don t imprint on the finished concrete and won t de laminate.
Work quickly when pouring concrete countertops but don t be sloppy or careless.
It will thoroughly blend the mix with much less elbow grease than mixing by hand.
And versatile to boot.
Clean the entire form with denatured alcohol to get rid of any excess silicone and debris.
The box is 2 wider than the sink mold on all sides and sloped in the front to follow the slope of the sink mold.
This concrete farmhouse sink not only looks good but is also hard working with two deep bowls and simple maintenance.
Don t mind that fancy copper patina in the sink.
Then add a thorough coat of a release agent spray to help prevent the concrete from sticking to the edge liner and sink knockouts.
Choose a high strength concrete mix it doesn t need to be a countertop mix but that variety is also available.