To wipe out tear-out, call for backup
Backer blocks not only reinforce router-table cuts, they also double as miter gauges for keeping parts perpendicular to the fence more reliably than a miter gauge. Use the drawing, top left, to assemble a backer block from 3⁄4 " scrap sheet goods, or customize it to suit your needs. One advantage of a base this size is that you can trim away the routed edges and use the block again with a different profile. You also can modify the block to cut tenons on end by gluing on a vertical support to steady the workpiece and a heel to push it into the bit.