Bracket 19mm Tube Holder

I have made Improvements to this bracket see http://www.thingiverse.com/thing:1000680

I designed this bracket for my new cabinet to hold a 19mm round wardrobe pole from a DIY store, I printed it solid and include a second round ridge under the main collar to increase strength. I'm not an engineer and not sure its exact load capacity if anyone has suggestions or advice who is an engineer that would be great?, I include the openScad file I created so feel free to modify for your own use, or che