The hub is built from 5 disks cut from scrap plywood on the CNC.  The layer that will be the face of the clock is a full disk with a recess for the battery-operated clock mechanism.  The remaining layers are hollowed rings.  Each layer has a set of 1/8" alignment holes to aid in gluing.  The ring on the right has notches cut for the screws that will fasten the spikes.

A quick test to see how the radius on the spikes fit.  I had cut the spike radius slightly larger than the plywood hub pieces to account for the veneer that would be applied to the hub.  So, the slight gaps you can see here should disappear after the veneer is on.

The final ring has a recessed shelf that will support the removable back piece.

With all the hub pieces de-burred, it was time for the glue-up.  I left a little of myself in the glue-up with dabs of blood from a cut on my thumb that I got when cutting the alignment pins with a utility knife.

With glue applied, I clamped the layers until the next day.

Time to make a final decision on what veneer to use to cover the hub.