I have received delivery of some 6 inch tubing they are about 8 foot long I think they might be used for sighnage on roads as the lad that gave them to me works for a road maintenance company and said they were taken down and going to scrap metal anyway so not hot or anything like that but am wondering would they be good enough to hang 8 or 10 foot light gates off of I was going to sink them 3 foot and concrete them they look fairly strong, I could fill them with strong wet concrete to strengthen them up a bit if required, what we think would they do the job
I think you'd want at least 3mm wall for gate posts.
However, if the gates were sub 12ft then they would work. They would not stand kids swinging on the gate as well, but should be fine for a normally closed gate.
Few lenghts of reinforcement bars in them and then good wet concrete with a good amount of cement in it, well compacted and they should be fine as all they would really be doing is acting as casing for the concrete. On there own they wouldn't have that much strength.
6" diameter , 3' down will last forever. I assume they're galvanized, if not try getting a plastic cap for them - stop water getting in n rotting from inside out.
