Saving your old wood columns.
Saving those old wood columns. First remove all the rotten wood and replace with Spanish ceder and seal with epoxy sealer. Column base if damaged beyond repair replace with a new one and coat with epoxy sealer. Or remove all damaged wood and replace with fiberglass resin and fiberglass mixture in one. Sand to shape coated with an epoxy sealer and painted with oil primer. Then remove paint at least 48″ up the column with a 60 grit sand paper power tools are recommended take care not to damage the column.. Now apply 2 coats min., epoxy penetrating sealer to seal the good wood. Next apply a coat of fiberglass resin about 46″ up the then the fiberglass fabric then more resin over the fabric to push out all the air. Now sand the column with 80 grit sandpaper to remove any rough areas. Next apply more resin to achieve a smooth surface be careful not to get the resin over the existing paint. now coat with oil primer and caulk all needed areas with NP1 caulking allow to cure before painting. PS if your columns were not installed properly the first time go ahead and replace them with fiberglass ones and be done with it.