You don’t need a biscuit joiner to cut biscuit slots. A slot-cutting bit in your router can do the job in most situations. Any 5/32-in. slot cutter will work, but special kits like this one include bearings that control the depth of cut to match the three standard biscuit sizes. Video: Become a master of biscuit joints!
A planer bit in your router isn’t the fastest way to flatten wood—in fact it’s pretty slow. But if you don’t have a planer (or if your planer is too small for the job), this bit is the solution. A standard straight bit can also flatten wood, but a planer bit provides a smoother finish in less time. Various sizes are available. See how to flatten wood with a router.