Petes Trash: May 2007

Hidden Door Bookshelf

brokenon May 6, 2007in home

rating25

intro

introHidden Door Bookshelf

Wall to wall bookshelves that conceal a hidden door. Made without casters.

My home office was messy. After I am done it will still be messy but now it is finished AND it has the secret feature. Well it was secret, till I wrote this.

In one wall of my home office is a 5 feet tall 2 feet wide door to access the storage area and crawl space under the garage. This is where we put holiday decorations, old stuff, and junk.
This wall was the perfect spot for floor to ceiling bookshelves , which I have done lots of , but it had this door in the middle of the wall. The perfect answer was a bookshelf that opened.

One day my father in law visited and we started drawing pictures of how book shelf hidden door could work , how to hinge, where to hinge, how to hide opening, etc. Following are the highlights from the journey that followed.

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step 1calculate dimensions

First thing I did was figure out how big and where a bookshelf would need to pivot in order to clear walls and neighboring shelves with minimum gaps. I positioned the hinge point 7"in from the right and 2" in from the front of the cabinet. For sanity I made a scale drawing of shelves and cut out the rotating shelf shape.

With a pin I tried different pivot ideas, validating my measurements. The goal was to have the vertical gap between moving shelf box and fixed shelves be covered with a single 4.5" trim piece.

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step 2Door Frame - moving steel frame

The next key insight, thanks Jim, was to build a steel frame rather than trying to hinge the wood shelves directly. This would allow the door to swing easily and support 500-1000lbs without a problem ( full bookshelf). I calculated the size for the frame allowing minimum clearance from the floor for trim and base board (2" ) and enough clearance from the ceiling for the metal frame barely below crown. ( 5") and the width was set to just cover the access door and be centered ( 42") . The steel 2x2 box was $90 cut to length with miters. I bought a couple of 3/4" bolts to act as the pivot pins. These were welded 7" in at center of bolt, from ends of the frame , and cut off to fit into 2x2 box anchors. My welding is not super, so I do a lot of welds.

The steel frame would pivot on a upper and lower anchor point, mounted to ceiling and floor respectively.

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step 3installing frame

The ceiling anchor was sized to span 3 floor joist and had a short arm out to avoid rocking (scrap steel). The pivot point on both ends was a 3/4 inch brass flange bearing inserted into a 1 inch hole in the 2x2 box. The floor anchor was much smaller as bolting to the concrete floor made it pretty damn solid. Good luck to the person that has to remove this someday.

This let me position and place the top anchor, base anchor, and frame. I attached top anchor loosely letting it rock, slipped in frame and bottom anchor on pin(with 2 washers on pin above bearing), then slid the whole set into place. A plum bob hanging along the edge of the frame made it quick to tell if it was vertical in both directions. When true, I secured bolts on both ends. I tested the swing of the door frame with ~500 lbs of people standing in it. Dead smooth action.

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step 4add the wood

Into the installed frame I built the first shelf box for the swinging shelf and verified clearance. In my design I made the swinging shelf 2 inch shallower than the other shelves to allow clearance behind it for the arc when it swung. ( If I did this again I would bring all the shelves out from the wall, making all full depth. Then I built the two side shelves and installed trim all around. I used a credit card for gaps between trim and crown to allow clearance.

The 4.5 inch trim left and right of the shelf-door , the right side is fixed to the fixed shelf, the left side moves with the door. I had to bevel notches in the trim on the right because the horizontal trim dives under it as the door opens. I also had to slightly round the horizontal pieces to slip underneath smoothly.

I am not the best woodworker, and the materials ( mdf and particle board ) are less than optimum, and the walls are crooked, but the results were great. Nobody would ever see the finished wall and think "Hey I wonder if that is a door?"

all in all i have about $350 in the project.