Easy spindle repair saves disassembly
Turn a replacement part or use the old one if it can be repaired. You may need to shorten one tenon so you can wiggle the damaged piece into the original position. Drill a 1⁄4 " hole into the center of the shortened tenon deep enough to accept a 2"-long dowel and a ballpoint-pen spring. Next, bore a 1⁄4 " hole at least 1⁄2 " deep into the middle of the plugged spindle hole as shown in the drawing above. Apply glue to both ends of the rung and slip into place as you would reload a roll of toilet paper. The spring will push the dowel into place and, when the glue sets, the dowel will make the repair permanent.
—Earl W. Zieg, Fairfax, Va.