Help with aluminum railing mounting

By whiteyz Date 01-22-2009 13:33

Ok guys I am trying to come up with a different mounting system on an aluminum cable ray that will be mounted on the outter edge of the roof at a school ( couple hundred feet of it ). Everything is clear anodized also. The posts are 4x2x3/16 tube and the top and bottom rails are 4x2 also. The posts will be be bolted to some knife plates that will be sticking through the brick with aluminum zee's bolted to to both sides of the post that will bolt directly to knife plate. My problem is that this basically gives me NO room for adjustment at all. Also if the knife plates are out of plumb at all the post being 6ft tall will show greatly. I really need to come up with another way to mount this then submit it to see if it will fly. It's almost going to have to be built on site just cause I am scared of warping in the shop in the slightest amount. But being anodized I will have to come up with a way for everything to be bolted or screwed together. These posts are 3' on center so there is going to be alot of them. I will try and get a pic up of what I am looking at to see if anyone else has a better idea. Thanks

Attachment: 5608Sketch-Justin.doc (206k)

By DaveBoyer (*****)

Date 01-23-2009 04:16

If You do a search You will find a thread on welding anodized aluminum, there is a link to an article about Tuna Towers on boats.

My opinion is that unless You weld the joints it will look like a farmer built it.

With the mounting detail shown, You would have to use shims to get the posts plumb.

If the connecting part was an angle instead of a "Z" You could bolt through the 4" dimension of the post and locate the holes so that the posts are plumb even if the mountings are not. This would allow enough freedom that You could fabricate as large a sections as You can handle in the shop.

The top rail may tend to warp from the post welds. You can build a simple jig with a porta power cylinder to true it up after welding. One of the marine rail builders I know does this.