After 17 years, a gate post that a contractor had installed into a slab had finally rotted, and I was left pondering a solution.
First I rocked the post and broke through the last of the unrotted wood. Discovering that all the rot was below the surface, I was able to trim it off and use the original post.
First I used a 1 ¼” auger with an extender and drilled out as much of the old wood as I could. With the help of a 6' wrecking bar and a pry bar, I was able to break up and auger out the existing wood down to about 14”.
Next, I used a 2” spade bit with the same extension piece to drill into the bottom of the post 6”.
I glued a 1 ½” outside dimension 12” nipple using Gorilla Glue into the post. I then added a connector piece to lengthen it and give the concrete something extra to hang onto.
I let the glue dry overnight, then I inserted the pipe into the hole and attached it to my sawhorse in order to hold it level. So that I wouldn’t have to worry about the height, I added enough gravel so that when the pipe rested on the gravel, the bottom of the post was ½" above the concrete. This method should protect it from rotting in the future. (I took this into account when I trimmed the post.)
Before I mixed the cement, I made sure all my tools were in place and laid down cardboard to protect the existing concrete. I leaned the post to the side so that I could get the concrete into the hole easily, knowing that I could re-level it to my sawhorse while it was loose.
Carefully following the Rapid Set cement directions, I mixed the cement and filled the hole just about to the top. I then leaned the post the other way and found that I needed more concrete.
Once it was close to the top of the hole again, I leveled the post, carefully pushed the remaining concrete into the hole, and smoothed it with a trowel. I followed the recommendation to mist the surface of the curing concrete so that it wouldn’t crack as it cured.
Lastly, I let the cement sit overnight, reattached the hardware, and rehung the gate.