Taking the Mystery Out of How to Make a Concrete Sink Mold
With more and more architectural concrete companies offering various decorative sink lines, we present the following “how-to” guide so you too can make your own. Concrete is an attractive material with a unique quality look and feel. Concrete is a "perfectly imperfect" material, it will vary from piece to piece and that is part of its charm and uniqueness.
The following step-by-step uses Smooth-On's VytaFlex® 40 mold rubber to achieve perfect concrete sink molds that can handle multiple castings. Just remember that you can make a mold of just about anything so get creative in designing your new sink basin.
1 - The model: concrete sink basin.
2 - Sink basin is measured for dimensions. Acrylic coated boards are used to construct the mold box walls, spacer board and two baseboards.
3 - Basin is centered on the acrylic coated board.
4 - A pencil outline is drawn around perimeter of basin.
5 - Use a jigsaw to cut out the
circular pattern. This will be used as a spacer.
6 - Remove plug.
7 - Place sink on baseboard and place spacer on top.
8 - Mark alignment on baseboard and spacer board.
9 - Use modeling clay (sulfur free) to create gasket around perimeter of basin.
10 - This will prevent rubber from going underneth model.
11 - Placer spacer down over basin.
12 - Use modeling clay to fill in negative space caused by the spacer.
13 - Glue down acron nuts in corners for registration keys.
14 - Place one extra acron to help with alignment.
15 - Assemble mold box with drywall screws.
16 - Seal seams with hot melt glue.
17 - Release all surfaces with Universal Mold Release.
18 - Measure and dispense VytaFlex® 40 mold rubber.
19 - Mix thoroughly for three minutes, scraping bottom and sides of container.
20 - Pour VytaFlex® mold rubber 40 slowly over model. DO NOT COVER BOTTOM OF ORIGINAL MODEL. Exposed area will represent pour spout.
21 - Let VytaFlex® 40 mold rubber cure for 16 hrs. at room temperature (72°F / 23°C).
22 - Use modeling clay to fill in any surface irregularities.
23 - Place reverse baseboard down over cured rubber.
24 - Secure board with drywall screws.
25 - Turn over mold box.
26 - Remove original baseboard to expose model.
27 - Remove spacer board.
28 - Remove clay gasket and wipe surface clean.
29 - Fill any screw holes with modeling clay.
30 - Hot glue exposed seams.
31 - Apply Univeral® Mold Release to all surfaces.
32 - Measure and dispense VytaFlex® 40 mold rubber.
33 - Mix thoroughly for three minutes, scraping bottom and sides of container.
34 - Pour VytaFlex® 40 mold rubber over model and existing rubber to create second half of mold.
35 - Let VytaFlex® 40 mold rubber cure for 16 hrs. at room temperature (72°F / 23°C).
36 - Once cured, remove mold box side walls.
37 - Slowly remove top section of mold.
38 - Remove original sink basin.
39 - A perfect 2-part mold of the original model.
40 - Apply In and Out II® release
agent to all surfaces.
41 - Place mold between boards and secure.
42 - Place mold on a vibration table and fill with concrete.
43 - After concrerte cures for 24 hours, demold casting.
44 - A perfect concrete reproduction of the original.