Zephyr II Battery Box

Here's my battery box for the Zii.  I made it for two reasons:

• I needed a bit more room for these 4000 mAh cells, so I trimmed a bit from the front and back of the battery compartment.
• Other people have commented that crashes were crunching up the Zii nose, and that a plywood battery box helps prevent this by transferring the crash energy to the rear of the body where there's more foam to absorb the energy.

Here's the cut I made to the the front and back of the battery compartment.  I made it flush with the leading indentation.

Here's a closeup of the front cut.  Ther was some epoxy sealing a gap... I used my Xacto saw blade to cut through the epoxy.

Here are the five pieces of the box.  I routed out two slits for the battery strap.  I don't have measurements as I just marked the cuts against the opening.

I started with the front and back walls, placing them flush against the front and back foam walls.

Next, the bottom.  It sits flush against the front and back walls.  Don't let those boards ride up -- the sides of the fore and aft boards should butt against the bottom board.  See the illustration below.

Finally the side walls.  Also shown are some hinges that I might use to hold the top hatch on.

Here's the side view of the box.  Be sure that the bottom and sides touch the flat surface of the front and back walls.  this will transfer energy from the front of the plane to the back if you nose in.