scmrak's Full Review: 4" X 3 - 1/8" Cedar West Coast Post Cap.
When we first moved in to the Great White Elephant on the Edge of the Prairie (an 1895 Queen Anne farmhouse in a small Illinois town) the kitchen porch was this close to collapsing under its own weight. One of the many POs¹ had haphazardly repaired the old porch at some time, and the whole thing listed badly on its rotting support posts. It lasted another winter, maybe two, before I simply demolished the old one and started over. The only thing that survived demolition was the 2x8 cedar ledger board; everything else I replaced. Instead of treated lumber, I went with cedar 4x4s for the corner posts and built cedar railings (much nicer than your typical deck railing, for what it's worth). The original posts included three-inch ball caps, which meant coming up with replacements: I matched the cedar posts with these three-inch balls: the cap is a three-inch sphere resting on a 3-1/8-inch turned, conic pedestal, and it attaches to the top of the post with a double-ended screw (supplied). The whole works is four inches tall, including ball and pedestal.
Since the pedestal is round and 4x4 posts are (duh!) square, the caps don't fully cover the top of the post and would look rather odd. The solution is to insert a second, flat post cap between post and spherical cap; a technique that in fact matched the original construction (an important point for historic houses) and lent the posts the requisite Victorian air (the ovoid "pineapple" caps are more gothic than Victorian). This second cap is drilled on-center to accept the double-ended screw, and can either be glued in place or tacked with a finish nail to prevent rotation. Using two simple finished pieces such as these to create a more complex shape is a common technique in carpentry (but don't tell anyone I told you).
These cedar ball post caps took the outdoor stain we chose quite nicely; and create an attractive, authentic appearance on the porch railing. In addition, caps such as these also function to protect the exposed end of the post from rain and snow, which would hasten weathering. Cedar is rot-resistant, and will very likely outlast the less expensive treated caps, which are prone to cracking because of differential swelling and shrinkage from the treating fluids. I would only caution users to be certain that they inspect the balls for cracks or knots. I had no trouble, but I found these at a Menards lumberyard, which seems to me to carry higher-quality deck and railing parts than do the nationwide BigBox stores.
¹ "PO": old house owner slang for "previous owner" - typically used as a curse
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