GETTING STARTED

Soapstone is softer than marble or granite consequently fabrication and installation can be achieved with most handyman tools. Soapstone slabs weigh approximately twenty (20) pounds per square foot. Due to the excessive weight of the stone, adequate support and assistance is recommended.

CUTTING

A medium priced (approximately $40-$50) 7”or 8” turbo diamond dry cut blade works well to make the cuts, which is available in most hardware or building supply stores. Most fabricators cut the soapstone using a circular saw with at least a 13 amps capacity. It is advised to put masking or duct tape on the metal foot of the saw to avoid scratching the stone. Take care not to drag tools or objects across the stone as it may scratch.

When cutting a soapstone slab make sure the stone is flat and fully supported to prevent breakage at the end of a cut. If sturdy benches or tables are not available to work on, 2 x 4’s or 4 x 4’s on the driveway or garage floor works well. A carpenter level or straight edge clamped to the soapstone makes it easier to make a nice straight cut.

If possible it is recommended to try equipment on an extra piece of stone to familiarize you with the stone.

Let the diamonds do their work, don’t force the saw. The blade will heat up causing it to warp. Use light pressure on the saw for a clean straight cut.

FINISHING

To finish the edges sand the face until the saw marks are removed and then sand the top and bottom edges. This can be achieved by using a sanding block and 80 grit sandpaper. Carefully rounding the sharp corners to an 1/8”radius, then finishing with 120 grit to match the top surface. If you use a power sander be careful. It is recommended to try it on an extra piece of stone. Routers with carbide or diamond bits can also be used to get different profiles.

INSTALLATION

You can place the stone right on the cabinet with out a plywood sub-top, if the cabinets are sturdy and well made. If you have a sub-top you can cover it with a shoe-base molding and finish it the same as the cabinet.

SINK CUT-OUT

When marking the sink cut-out overhang all around the sink about ¼”. It gives a good appearance and is easier to clean and maintain. Use a hole saw to cut the corner radius in the countertop, and then use the circular saw to cut the straight lines between the holes. You can also use a 4½” angle grinder with a turbo diamond blade to cut and shape the larger radius and then to clean up the corners. Make sure the sink cut-out is fully supported, as it will drop down when the last few cuts are made. Finish the edge like you did the front countertop edge, you should relieve the top and bottom sharp edges in the sink cut-out. With square sinks it is possible to just hang the counter slabs ¼” over the edge of the sink and put a soapstone “rail” in front and back of the sink to join the right and left countertop side slabs. Use a (wood) whole saw for the faucet holes or a tungsten grit whole saw will cut faster.

KNIFE-GRADE BLACK STONE-GLUE

Use knife-grade black stone glue (polyester resin with a cream hardener) as the stone will go black with oiling and clear glue or colored glue won’t change with the stone color.

DRY FIT FIRST

Dry fit the countertops first making sure everything fits and looks good because once you glue the stone, it’s done.

Make sure the counters are level and the seams are even. You can use glaziers horseshoe shim to level the counters if the cabinets are not perfect. Use the shim about every 6”, so the slabs are fully supported underneath. You may set the slabs with a good construction adhesive or silicone. It is recommended to seam the counters in place rather than seaming elsewhere and moving them to the cabinets.

TEST MIX GLUE

Make a test mix of glue to see how much time you have to work with. Ambient conditions such as temperature and humility can change the pot life and set up time for the glue.

GLUING THE SEAMS

Separate the pieces to be seamed about a ½” on the counter surface. Put masking tape along the sides of the seam about ¼” from the cut to keep the excess glue off of the soapstone. Make sure the areas to be glued are clean, dry, and free of dust. Follow instructions to mix glue, using a black pigment to color the transparent knife grade glue. Mix in the hardener as directed with a spreader knife on a piece of tile or stiff plastic board with a plastic spreader knife. Butter both sides making sure the glue fully covers the edge and push them together. Use a spreader knife to take off the excess glue coming up from the seam, be careful not to dig any glue out of the seam. Once the seam is tight, carefully remove each tape strip on the side of the seam taking away the excess glue and let it set up.

SANDING

Once the glue has set up sand an area about 8” to 10” on either side of the seam with 220 grit and you will see the glue disappear to a thin line. (Cobra and Mumbai Grey from India are finished to a 400 grit.)

After the seams are sanded you can put a bead of black silicone along the cabinets and sink.