While cleaning up my workshop, I decided to sell an old table that I had been using as my outfeed table. I decided to replace it with this drop down extension that can move out of the way when not in use. For my particular case it was important that the surface be below my actual router table surface and extend out in front of it a few inches. I designed this hinge and support system to use a piece of ¾" plywood as a drop down extension table. When raised to the horizontal position it will slide forward about 6" giving me exactly what I needed. It uses ¾" PVC pipe for the hinge pin and for the support rods. When not in use, the support rods store behind it out of the way so they won't get lost.

While I used this for an outfeed table, it could easily be used for a drop down wall mounted shelf or light duty work surface. I tested it with my 45lb vertical clamping mechanism and it didn't flinch.

There is one wall bracket that is open with a plug so the pin can be inserted/removed without removing the bracket from the wall. There's also an additional open bracket to go along the length of the pin (in the middle in my case) for additional support. You could theoretically make a drop down shelf up to 10ft long using the additional brackets along the length to keep the pipe from flexing.

I printed it in PLA because that's what was loaded, but PETG would arguably be a bit better. I used 3 walls and 15% cubic infill. All parts are screwed to their pieces with #10 pan head sheet metal screws.