Thanks for the reply. I am curious if you mean to not worry about the cut the bit is making just focus on cleaning up the cut with the mill file? I see the bits you suggest but may I ask if the length of the cutting edge of the bit affects the smoothness of the cut? Do I need a short or long 2 or 3 flute? May I be as specific to ask you to tell me which bit on the link you sent me? Thank you for your time
The cutting length has noting to do with smoothness. Only a small part of the cutting edge (the thickness of the veneer) makes contact. Common lengths are 1" for cutting edges. The further the bit is extended, the greater the possibility of cutting into the face where the bearing rides, if the router is tipped at all. This applies to handheld use.
The length of the cutting edge gives the opportunity to have a variance of sharp edge to use over time. In reality, a short cutting edge is all that's necessary, ½" will do. I recommended a 3 flute bit (¼" shank, ½" diameter), to cut the smoothest.
Using a mill file with the veneer face up, hold the file flat to the substrate and push the file into the veneer on the push stroke only using the edge of the file to cut the veneer. The handle of the file should be at a slight angle towards the direction of movement, so the file cuts on a forward/down stroke. This can be done in lieu of routing.
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