Limber and Lego

I use a Plastruct 1.6mm Buty. Coated Wire number 90102 as the axle.  These are hard to cut and I use a big pair of wire cutters.  The metal is very tough so make sure you have a good cutter for it.

The groove in the brick should be deep enough that the wire will fit below the level of the edge of the brick.

I use a tiny rat tail file that is only slightly larger in diameter to the wire.  Tools like this are found in model railroad shops.

Here is the file in the brick.

Since the file tapers it should file the brick from both sides.

Once the groove has been made glue a bit of sheet styrene to the bottom of the brick.  I use Evergreen Scale Models .040 thick plain sheet plastic or thinner.