What gate post on concrete?

[PscottDIY]

Hi Chaps, my latest conundrum;

re-purposing an aluminum slat gate down the side of the house. The gate is approx 1500 wide. Issue I came across today while trying to install is that the post i bought and installed whilst being firmly bolted in to the concrete the post is 50mm aluminum and too lightweight and flexes way to much to support the gate. Back to the drawing board, what type post should I use ?

  

[JacobZ]

Hi @PscottDIY,

Thank you for your question about your aluminium gate post.

Are you planning on putting anything to the right of the post?

Aluminium tends to be quite soft and flexible when compared with other metals such as steel, but a lot of your issue is because the post is not braced to anything horizontally. If the fence was extended, the aluminium slats would transfer some of this load sideways into the next post.

A steel post such as this RapidFence 50 x 50 x 1300mm Flanged Steel Fence Post is going to be less flexible, but it would likely still have some issues if it is not braced horizontally.

Let me know what you think and if you have any further questions.

Jacob

[PscottDIY]

Yes thinking steel will be the way to go. I have a family member going to weld up a frame for me which I will then infill with the slats. 2 things : - 65mm or 50mm steel ? 
- what’s the best way to level the concrete so the base plates are on an even footing? , frame something like this ;

 

[JacobZ]

Hi @PscottDIY,

I'd just choose the width that matches your gate the best, the dimension of the post won't make a huge difference, just make sure they use decently thick steel such as this Australian Handyman Supplies 50 x 50mm Galvanised Steel.

The concrete looks fairly level already, so the easiest way to set the post level is to use packers under the base plate before bolting it in place. Once bolted down, you can use a hammer and chisel to cut them flush with the edge of the base plate, so they won't be visible.

Let me know if you have any further questions.

Jacob