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Concrete Vanity: De-Forming, Polishing and Installation The final chapter, wherein Derek, Dean and Dan unveil their finished handiwork. From "Rock Solid" episode DROC-202

In this final phase of the concrete-vanity project, the form is removed from the hardened concrete, the surface is polished smooth and the unit is installed.

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	Before
	After

De-Forming and Polishing the Concrete

Tools and materials:

cordless drill
flat bar or crowbar
grinding wheel or metal file
bolt and hammer
garbage bags
water fed grinder with diamond pads, various grits
potassium silicate
bowling alley wax
clean rags and paper towels

	Figure A
	Figure B
	Figure C
	Figure D
	Figure E
	Figure F

• Uncover the concrete after it's set up for about 48 hours and then de-form it. Clean the concrete residue off of the tops of the rails and the knockouts with the flat bar. Remove all of the screws from the form – and don't forget the screws holding the smaller knockouts to the form. As each edge is exposed, smooth its corners with a metal file or grinding wheel – this makes that edge less prone to breakage.

• De-form the smaller backsplash shelves first. Remove the rails and pull off the shelves. This may take a little elbow grease because they may be attached to the melamine with silicone – but be careful as you work, this concrete is green (new and not at its final strength) and easy to damage. Set the backsplash shelves aside.

• Remove the curved and side rails of the main vanity piece and double check that the screws have been removed from the knockouts. Flip the form onto the remaining rail and then carefully onto its back (figure A). It's helpful to have several people helping. If the melamine doesn't immediately release, gently bend it till it does. If you have difficulty removing the remaining knockouts, you can tap them gently with a hammer and a small wooden block or blunt instrument.

• Once you de-form the concrete, let it set up for a few days before grinding to expose the buried glass. Concrete takes 28 days to cure completely, so the glass is still harder than the concrete that surrounds it – which helps for exposing the glass. Dan recommends renting a water-fed grinder, moving to an area where you can work with water, and wearing garbage bags – this is a wet process (figure B).

• Start grinding the surface with a 50-grit diamond pad on the grinder and work in a circular motion with steady pressure (figure C). Be careful as you work around the edges--they're still easy to damage. Continue to use the 50-grit diamond pad until the buried glass is exposed (figure D). Follow up with finer grit pads, working up to 400- or 800-grit diamond pads. What you're trying to create is a finished surface that's smooth to the touch and has a matte sheen when dry. If you have backsplash shelves like ours, you can save yourself some time by not grinding down the area they'll sit on.

• Let the vanity pieces dry.

• Seal the countertop by spraying it with potassium silicate, a densifier. Apply the sealer until the concrete surface and sides are thoroughly wet but not dripping (figure E). Wipe off excess sealer (figure F) and allow the surface to dry.

• Finish off the vanity top by applying bowling alley wax. Take your applicator and apply the wax in a circular motion. Follow up by wiping it off with a dry terry cloth towel.

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