to provide positive drive between hub and blade the blade sides of the inner plate 23 and the outer plate 20 have radial grooves or slots 36 and 38 respectively which segment the surface of the plates in a pie like fashion when saw blade 14 is assembled with the plates passageways are formed at the slots 36 and 38 through which coolant can flow along the radial lines beginning near the center of each plate and extending outwardly toward the perimeter of each plate a collar 25 is fitted over the inner hub 16 and separated therefrom by o ring seals 24 and 26 an inlet fitting 27 affixed about an opening in collar 25 provides a means for connecting an inlet hose 28 such that coolant can flow from the coolant supply 29 along the path a 0 and into the fluid inlet cavity 30 by directly connecting the inlet hose 28 to the collar 25 coolant can be introduced to the hub assembly under positive pressure the inlet hose 28 is routed away from the saw blade so as to avoid damage when the saw is in use one way fittings 33 are attached to the collar 25 such that grease or other lubricants can be applied to the seals 24 and 26 and the rubbing surfaces at 29 and 31 this feature also provides a means for purging any coolant that might be trapped in the lubricating cavity and cause rust to form during periods of non use the hub assembly 10 is closed at the shaft end by means of a washer 32 which is affixed to inner hub 16 by means.