I built this binder over a few weeks ago.  The binder body is made from 1/4" soft aluminum sheet.  The brass pulleys were turned from solid brass bar stock, down to an inch in diameter, then center bored for the axle.  I used nylon spacers for the wide grooved pulleys, mainly because I made a mistake in measuring the center of the pulley groove.  The nylon spacers were picked up from the local Home Depot in the nuts and bolts section.  I used a 3" pulley as the drive pulley, and fashioned the turning handle from some 1/8" scrap aluminum, and 1" hardwood dowel.  There's a 1/2" nylon spacer inside the pulley hole, and I used washers to get the correct stand off distance from the binder body.  The cradles are made from 1/8" aluminum, with the cradles themselves cut oversized based on someone's recommendation on the list.  The binding thread "director" is made also from 1/8" aluminum.  The thread tensioners are made from 1/4 - 20 bolts, washers, compression springs, and a nylon inserted locking nut.  The binding thread "eye" is made from music wire, inserted into a 1/4 - 20 bolt that had a hole drilled in the top, then super glued in place.  The thread spool holder is a 1/4 - 20 x 7" bolt.