3'x3' Sign On One or Two Poles?

[Sven]

Is a 4"x4" square aluminum pole strong enough to support a 3'x3' 080 aluminum or poly-metal sign, or will strong winds likely weaken the joints or bend the sign in time?? I have five to install, and I'm trying to reduce the number of holes that need to be dug.

 

[Billct2]

You'll only have 16" unsupported so I would say fine, depending on how you fasten.
When I'm concerned about this type of mount I like to put double row of fasteners (probably thru bolts) instead of one set down the middle.

 

[Gino]

Is this a center mount on the pole or a yard arm type hanging sign ??

One or two sided, in other words.

 

[HIGHSPEEDGRAPHIX]

Yeah you will be ok with .80 or dibond. you could always put horizontal braces and inset a few inches top and bottom, to double prevent the sign from being bent. depends on the asstetics of the back of the sign if you want to there.

 

[Mosh]

Lots of stop signs are 36" and they for the most part are .080 and on one post.

 

[FS-Keith]

Do not use a composite for something that big. I would use .080 alum for a 3x3 panel, drill and tap 3- 3/8" bolts

 

[tsgstl]

If they are real estate signs or somewhat temporary then you will be fine with composite panels. Use fender washers and or string 2 3' wide 2"x4"s for added support on top and bottom between the sign face and post. Mdo is only a little more expensive and solves all these problems though.

Edit: don't listen to anything I just wrote I totally miss read your original post
You should be fine with composite, but I have seen it fold and pop through fasteners. .080 bolt through like mentioned is the way to go.

 

[Moze]

I would use .125" aluminum and run VHB tape at the very edges of the 4"x4" - from the top of the sign to the bottom. Then a few dollops of silicone between those strips of tape - like every 6" or so. One bolt at the top, one at the bottom, washers behind the panel to match the thickness of the VHB tape. It won't go anywhere.

 

[skyhigh]

Lots of stop signs are 36" and they for the most part are .080 and on one post.

But the "U" post flexes & twists with the face. His 4x4 post will not move, thus putting a strain on the fasteners.
If these are not "pretty" signs, then you can abandon the 4x4 and use the U-channel & .125 for the face.

If you're locked into using the 4x4 aluminum post, then do as Moze suggests. His is good advice (quick and easy too)

I would use .125" aluminum and run VHB tape at the very edges of the 4"x4" - from the top of the sign to the bottom. Then a few dollops of silicone between those strips of tape - like every 6" or so. One bolt at the top, one at the bottom, washers behind the panel to match the thickness of the VHB tape. It won't go anywhere.

 

[Marlene]

how are you mounting it? pole in the middle? pole on one side? hanging from and arm? what kind of hardware? the only one I can see that might give you problems is the one pole on one side.