Second Shelf Attachment

Yes, the second shelf appears to be attached just fine, resting on two rails and a tongue and groove. However, the shelf was a tad warped and needed to be pulled down in the center of its long spans. Also the tongues and center could use extra support.

I glued two new side rails under the tongues for support, being careful not to glue the shelf, itself, because it needed freedom to expand/contract. The center support would be tricky because I can't use glue and I need to pull the shelf centers down without prohibiting movement. I decided to use figure eight screw mounts. A forester bit made a quick slot for the figure eight...

...which must be countersunk below the bottom of the shelf.

Using pocket holes to attach the center rail, the figure eight screw mechinisms allowed me to pull the warpped areas down onto their supporting long rails, without prohibitting movement. We'll see!