Build a custom L-shaped workbench of three separate tool benches that join to form a fourth work surface--a dropped well for your miter saw. Construct the base units of two-by four components surfaced with medium-density fiberboard (MDF) that can be replaced easily when scarred and dented beyond use. Use screws, glue, and double-faced tape to secure and join components.
Plan your workshop workbench carefully and diagram the dimensions. Make a cut list of pieces to cut, especially when several are the same size. Set up saw horses and lumber as a temporary woodworking bench for cutting components.
Transfer the bench leg length onto a two-by-four and clamp a stop block at the mark. Butt each two-by-four against the stop block as you cut to ensure consistent length. Repeat the process for each component of a different dimension.
Mark and then position a pair of bench legs for repeated cuts with a sliding compound miter. Cut half-way through each two-by-four to notch out matching mortises across each pair. When joined, the two-by-fours will become four-by-fours with a mortise.
Apply glue to the interior surface of each pair of leg components and their mortises. Sandwich a cross rail between the two and secure with screws. Glue and screw another brace across the top of the end frame.
Position and clamp together two end frames with two side rails for each workbench base. Attach them at the upper end and secure the rails with screws.
Lay multiple bottom braces/planks side-by-side to span the space between the cross rails. Secure each with screws driven through them and into the cross rails beneath to provide structural reinforcement and a handy shelf.
Measure and mark cut lines for workbench tops on sheets of 3/4-inch MDF. Use a clamping straight edge and a circular saw to ensure straight cuts every time. Attach tops to the bases with countersunk screws to avoid scratching projects.
Set bases in an L-shaped configuration, leaving a gap for the well. Span the gap for the well with two-by-four rails and slide in the top. Secure replaceable MDF panels on top of each bench top with double-faced tape.