posts in concrete

What is the best way to install traffic signs in concrete.Do I need a core drill about 12 inches wide or what??

Are you going to use a steel pipe? if so, then yes a 12" core would be easiest, you can also saw cut a square and jack hammer it out. If you are just installing the u-channel or tele-spar posts, then you can use a smaller diameter core. We have also used surface mounted plates, that bolt to the concrete. Here is a link to them [url]http://www.sa-so.com/egiWeb/Controller.jsp?pageId=5&i… [/url]

We have chiseled out a 4"x4"x4" Square with a 1-1/2" SDS Hammer Drill. We use 2" Square Tubing and set them with Shep-Rock or Rocktite. They set firmly within 10-15 minutes. Either Product is easy to work with & semi self leveling. More can be added to achieve a smooth finish to blend with the surrounding concrete. Domingo

I have seen some 2 5/8 post core drilled with a 3 or 4 inch hole in concrete. How do you get the hole cleared out, and what do you use to hold the post in, and how far down do you need to go? I need to install 21 posts with 60" from the bottom of the h/c sign this way and need a little help.

Core drill, drive the posts to depth, then backfill with patch.

Typically, I core drill a 4 inch hole and back fill with some type of quick set concrete. I've also used the "surface mount" bases. There's pictures of both on my website(signs page). I tend to shy away from the round 2 3/8 posts in concrete. I usually use the 2' square posts set in a sleeve.