Plywood Edge/End Grain

The convenience and power of plywood material is immediately compromised by problems and quirks resulting from plywood edge-grain. The cut edges of ply are far from the Euclidean ideal we'd prefer. Voids (both small and large), tear out, and gaps due to delamination cause plywood edges perform quite poorly as a surface.

Good Materials

Real quality baltic birch and MDF do not have this issue. BB simply has enough quality that the edge is a real surface and carries enough beauty to even stand on its own. MDF is really just an isotropic billet material.

Filler

DAP "Plastic Wood" filler works decently well to obscure the voids and imperfections in regular edge cut. However, this extra step takes time and effort. Relying on such filler:

1. Adds an extra 2 hours of cure-time to the project.
2. Adds substantial labor for application.
3. Adds yet another round of sanding (the edge must be sanded before and after application).
4. Requires paint to be the final finish of the project.

Tearout

When cutting up ply, tearout is pretty hard to avoid. The creation of tearout is not terminal for a project, but will add costly finishing steps later on and even in the best case lower the aesthetic appeal of the result slightly.

Tearout can be avoided by:

Cutting a 'clearance groove' first.

Cutting a groove in the bottom of the ply first will pre-cut the fibers at the bottom of the sheet first. Then raise the sawblade all the way up so that cutting action on the top of the ply is as vertical as possible. This cuts all top-surface fibers directly downwards.

Using a better blade.

Sharp, carbide blades with higher counts of teeth (50 to 80)

Choice of ply.

Some plys (laminate, for example) don't tearout badly at all. MDF-sandwiched is the same.