Removing The Old Wooden Balusters
Cut through the middle of the old wooden balusters using a circular saw. For long handrails you might want to leave a wooden baluster or two in the middle for support until you have some of the new metal balusters in place.
Remove the top halves of the wooden balusters from the handrail. The wooden balusters may be glued or nailed into the handrail and require twisting to get them out.
Remove the bottom halves of the wooden balusters from the floor or stair tread. Balusters can be attached in a variety of ways including toe-nailing, glued dowels or screwed in with a double-ended baluster screw. You may need to pull or unscrew them.
Drill the Holes
Drill the first test hole for the metal balusters. Often metal balusters require different size holes than wooden balusters. 1/2-inch metal balusters require a 3/4-inch hole at the bottom and a 1/2-inch hole at the top.
Drill the remaining holes into the handrail. The holes need to be at least 1-1/2 inches deep into the bottom of the handrail.
Drill the remaining holes into the stair treads. Holes should be 5/8-inch to 3/4-inch into the tread. It is possible to square up the holes with a chisel and avoid the need to use baluster shoes.
Installing The Balusters
Cut the balusters to length using a circular saw or chop saw with a metal cutting blade. Measure the distance from the bottom of the handrail to the top of the stair tread and add 1-3/8 to 1-1/2 inches. Each baluster must be measured separately because they vary in length depending on how far out on the step they are.
Remove any burrs on the cut end of the balusters using a grinding wheel or file and test fit your baluster.
Prepare the baluster and the holes. Slide the shoe onto the bottom of the balusters and tape it in place to keep it out of your way. Apply epoxy or adhesive to the top and bottom holes.
Install the baluster into the hole. Slide the baluster up into the handrail. It should penetrate deep enough to allow you to clear the tread and drop the bottom of the baluster into the hole in the tread. Add any epoxy necessary around the balusters.
Remove the tape and drop the shoe into place. Square shoe and baluster up with the tread. Allow the epoxy to dry and tighten the set screw on the shoe.