Adding to Ed's description... there is an additional 5th consideration... "Knowing how to work with the material at hand."
Specifically, you are working with a plywood with a thin "Veneer"... If you use some blue tape to cover the edges of where you are going to route, Mark the edge with a pencil... Then score that edge (the veneer) with a craft knife (scoring the veneer), then you can cut it without all that tearout. Just scoring without tape would help. The tape would add extra support to keep the veneer from "lifting."
Another method would be to back the veneer by using an edge such as hard board at the edges, so that it acts as a zero clearance backer to help support the veneer and help it get cut cleanly. (To hold the veneer in place as it's being cut...)
"Don't worry, I saw this work in a cartoon once."
"Usually learning skills and tooling involves a progression of logical steps."
Last edited by MAFoElffen; 11-30-2013 at 02:47 PM.