I had to make some fluted columns for a fancy entry. Flutes are typically milled using a core-box bit in a router with a guide mounted to one side. But a router will sometimes wander a bit when used with a single guide, and flutes have to be straight as pool cues, or they look awful. As shown in the drawing, I eliminated the problem by adding a second guide.
I put a 1-ft. long 1×1 extension on each guide to ensure good bearing along the edge of my workpiece. Then I linked the two guides with a pair of 20-in. steel rods. I used a couple of sprinkler control rods with their ends cut off. They fit just fine. Trapped between the two guides, the router couldn’t veer off course.
I held the workpiece in place with a 1×2 at each end. The 1x2s also acted as stops at the end of the router’s pass. I set the spacing, ran the router down the board, turned the router around and went back down the other side of the board. Then I reset the spacing and repeated the passes. This method is surprisingly quick and accurate.
Genet Wikoff, Los Angeles, CA