Paradox Box



Introduction: Paradox Box

A paradox is simply a contrary expectation, allowing for wonder and thought, opening the door for creativity.

Here is a box that unexpectedly opens on either side, take your pick!

Improbably, both sides can easily function as an opening OR a solidly connected hinge. A parabox?

The box also incorporates a fable by the Greek poet Archilochus, 680 - 645 BC.

"The fox knows many things, but the hedgehog knows one big thing."

This statement contrasts two ways of reasoning. The fox is wide ranging in thought and action, opposed to the hedgehog's single minded defense of rolling itself into a spiked ball. Objective analysis vs subjective focus, a floodlight vs a laser, a thinker vs a doer. The paradox is that both strategies are very effective, both with obvious pitfalls.

Which is the more effective process? The answer is given at the end of this instructable.



3" PVC - 5 3/4" length.

Scrap wood glued to 1 1/4" thickness.

Spool of black 5/8"width woven fabric ribbon (Offray).

4 - 5/16" rare earth magnets (Harbor Freight).

8 - # 6 x 1" wood screws.

Contact cement.




Disc sander (useful).

Jig saw.

Drill press.

Hacksaw with fine tooth blade.

Drill and bits.

Access to vinyl cutter/plotter and vinyl.

Follow all standard shop safety procedures.

Step 1:


Cut a section of 3" PVC pipe 5 3/4" length. The cut must be an exact 90 degree end cut. I used a disc sander to true both ends to 90 degrees.

The wood end plugs must equal two thickness of the 5/8" fabric ribbon used for hinges (described later) , or 1 1/4" total thickness. I glued up pieces of scrap wood to achieve the 1 1/4".

Mark (compass) and cut out (jig saw) the two wood circles so they are slightly oversize of the inside diameter of the PVC pipe. Drill a center hole (drill press) to accommodate the truing jig axle described below.

To get an exact fit for the wood end plugs use the jig pictured along with a disc sander. Clamp the jig to the disc sander table (table set at 90 degrees to the disc ) with the out most edge of the wood circle just touching the sanding disc. Gradually moving the jig towards the sanding disc while slowly and carefully spinning the wood circle around the jig's axle will allow you to sneak up on an exact fit. Focus and mind the fingers.

Step 2:


Epoxy the wood end plugs flush with the PVC ends. Roughen the epoxied areas to insure a good bond.

Drill 4 holes in each end at 2, 4, 8, and 10 o'clock positions, 1/2" from the edge. Install #6 - 1" wood screws being sure to countersink so they are flush with the surface of the PVC. The screws are necessary to stabilize the wood plugs once they are cut in the next step.

Mark a center line along the length of the box, then mark 3/16" lines on either side of that center line. This 3/8" section will be cut out and actually helps balance the round box when placed on a flat surface.

Step 3:


I cut out the 3/8" middle section with a fine blade hacksaw, slowly going around the outside, alternating the cut on both sides of the center line. The cut was made while the box was lightly held in a vice, wrapped with a towel for protection.

The rough cuts were sanded smooth by rubbing each side on a flat surface covered with successively finer grades of sandpaper.

Mark a center line down the middle of each inside half. 1/2" in from the ends mark the center to drill four 5/16" shallow holes to hold the rare earth magnets. Take care in drilling these holes so proper alignment of the two halves will occur. The magnets will hold the box closed when completed.

Epoxy the magnets in the holes flush with the surface (roughen the back surface/sides of the magnets). Note the polarity of the magnets before you epoxy them in place to insure the lid halves will attract, not repel.

Step 4:


The hinges are based on the popular falling blocks vintage toy called a Jacob's ladder.

The hinges are 4 - 5/8" x 24" lengths of a heavy weight fabric ribbon. They are wrapped around the box in the pattern illustrated above.

The two inner "B" ribbons are attached in the opposite direction from the two outer "A" ribbons.

Use contact cement to attach the ribbon everywhere but the inner diagonal crossover pieces. Note the two halves are shown slightly separated in the illustration for clarity. I discovered that contact cement will bleed through on any light colored ribbon. Follow the manufactures directions on how to use contact cement. I used the small bottle of Weldwood, comes with a brush.

Start by gluing each of the four ribbons to the flat part on one of the box halves. "A" ribbons going in the opposite direction of "B" ribbons. Next glue the ribbons to the outside of the first half of the box. Then position the four unglued crossover ribbons. Temporarily clamp the two sides together and glue the ribbons to the outside of the second half of the box. Finally unclamp and open the box (one side at a time) and glue the ribbons to the flat section of the second half of the box. Trim any excess.

Step 5:


The graphics (SVG file) are cut with a vinyl cutter/plotter and placed in the appropriate positions. Research tips for applying sign vinyl if you are inexperienced,

The graphics are optional. I have also made this type of double hinged box using more traditional square wooden box construction methods.

Step 6:

The Answer

Who has the more efficient strategy, the fox or hedgehog?

The answer lies in the way the box functions.

Both sides of the box cannot be opened at the same time. However, each side can be opened individually. Also the box stays balanced despite it's circular shape.

The most efficient strategy is to think like the fox when required, switching to the hedgehog when necessary, and visa versa.

The trick perhaps is knowing when and where.

The box is a reminder to stay flexible and balanced in your thinking.

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