Plan seams so that they are not next to sinks. To join countertop sections, use this process:
1. On a sturdy, level surface, set out spacer bars of uniform thickness and place the countertop sections on them. Between the slabs, leave a gap slightly less than the width of a straight-edge router bit.
2. Clamp on a sturdy straightedge to use as a fence and run the router down the opening, so that the bit shaves off a thin section of both edges at once. This will create edges that mate perfectly.
3. Then set up for mechanical strengthening and aligning of the joint. There are two options:
- Cut slots for standard wooden "biscuits," using a biscuit jointer.
- Or rout out the necessary holes for the type of tight-joint fasteners typically used to connect sections of laminate countertop.
4. Glue the joint using a slow-drying, two-part epoxy. Tint the epoxy by mixing in some of the sanding dust from the countertop. Once the joint has cured, lightly sand it to blend the seam with the surrounding area.
It's also possible to seal joints with standard caulking sealants. Typical areas for this treatment are the underside of the backsplash and around under-mounted sinks. Use a moderate amount of caulk in a color compatible with the countertop.