Home and Office Improvement: Box Holding Brackets. I Made It at TechShop.

Background:
      At times, we might have need to hang a box on a dry wall or metal cabinet.  Or we simply need the bracket to rest against the wall.    How could we accomplish in a practical way?

Goal:
        Make a bracket that could use tiny nails (like the ones used for picture hooks).  Adapt similar bracket and use magnets to hold the bracket sides of refrigerator or metal cabinet.

Design Consideration:
        I made a design that user could shoot small mail at an angle to the drywall.  Make sure the nail is long enough.   Upto 4 nail could be used.
        The height of the bracket could be adjusted so that it fit different box thicknesses.  Similarly, the bracket could be made Left or Right hand side or Top or Bottom position. 
        To avoid damaging the nail holes, I drill each hole by a drill bit in a screw driver (see picture).  Since the drill bit is long, I have to constraint it while drilling it so it point to the intended direction.   I think fit all the 4 nails and check the alignment (see picture).
The next paragraph  attempt to explain why the drill bit need to be guided despite the hole suppose to be straight through.

3D Printing Lesson Learned:
       Normally, one could use 10% ( or 25% ) fill to get a relatively strong part.  The solid part that merged with the flat solid portion was also filled using 10% (see picture).   ideally, I prefer that the tube is 100% filled across the depth to make it stiffered.   If the part of the bracket become too weak, them we could try 50% to 100% fill next time.  I don't think the amount of time woiuld increased by same proportion. 
      I wish MakerBot software could create separate zones where the users might want a different % fill.  Should anyone has a work around, please let us know.  Thank you in advance.

Additional Note:
    Always use 100% fill for final parts whenever material strength is required.