The diameter of {HEAD ~ the head sprocket} 8 must be sufficiently large to prevent {TAIL ~ development} of excessive stresses in the wood fibres of the wood components of the assembly 7 
The diameter of { HEAD ~ the head sprocket } 8 must be sufficiently large to prevent { TAIL ~ development } of excessive stresses in the wood fibres of the wood components of the assembly 7
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH