A strap winding mechanism for the winding of truck load straps and the like comprising a stanchion having a clamp at the lower end thereof for generally vertical demountable attachment to any selected stake hole of a conventional flat bed truck. The upper end of the stanchion has a plurality of generally horizontal journal apertures at various azimuthal attitudes for selective journalling of a reel handle and a bifurcated open-ended reel assembly in any of the journal apertures. The reel handle and reel spindle are threaded complementarily and thus readily assembled and readily reversible in the journal apertures, and readily disassembled for compact storage.