Some Router Bits Need an Offset Fence
I have a pair of edge-banding router bits (eagleamerica.com, No. 190-2075), but whenever I use them I get snipe at the trailing end of my plywood panels and the solid-wood edge-banding. What am I doing wrong and how can I fix it?
Michael Bourg, Weaverville, CA
The bit that cuts the plywood panel PANEL profiles the entire edge, leaving none of the original surface riding the fence. This creates a gap between the panel and the router fence on the outfeed side of the bit. So near the end of the cut, when the workpiece clears the infeed fence, it is free to plunge deeper into the bit, removing more from the trailing end than the rest of the workpiece.
The solution is to make an offset fence, where the outfeed side sticks out just a bit extra to make up for the wood you are removing from the edge. An easy (and temporary) way to do this is to tape a shim to the outfeed side that fills the gap between the panel and fence.