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Ace, Aceca & Greyhound Forum / REPORT - New splined stub axle's from Winchester
« on: October 11, 2012, 13:08:32 »
Nigel's set up certainly looks beefy enough and the last post obviously answers the concern on the securing of the retaining nut, this is one solution to the problems in hand.
The assembly of the original AC rear stub axle assembly is critical in its original form. The pre load and positioning of the bearings is critical and can only be achieved in conjunction with full contact of the taper on the stub axle, The key way only represents a percentage of the drive load required, the majority of torsional drive should come from the correct linear load and full seating of the stub axle taper to drive hub.
Any damage, corrosion pitting, grinding marks or disparity between tapers on the hubs and stub axles will reduce the coefficient of friction between the two components also the incorrect linear prelaod on the tapers due to incorrect assembly to achieve the correct pre load on the bearings will result in the reliance of the 'Key' having to transmit more torque than its design limits.
There are stress risers associated with the key way and is more likely to be a point of failure coupled with incorrect material specification or heat treatment if all is assembled correctly.
We have found that if the assembly of these items is carried out correctly to the correct specification the original design is capable, with good reliability, of transmitting 150 FT/LB of torque for a 900KG car on 550x16 Dunlop Racing and 200 Ft/Lb for a 750Kg car on 550x16 Blockley 5 std tyres. On these two examples we have 'Never' had a stub axle breakage or significant key way enlargement in 7 years.
www.bristolengineering.co.uk
The assembly of the original AC rear stub axle assembly is critical in its original form. The pre load and positioning of the bearings is critical and can only be achieved in conjunction with full contact of the taper on the stub axle, The key way only represents a percentage of the drive load required, the majority of torsional drive should come from the correct linear load and full seating of the stub axle taper to drive hub.
Any damage, corrosion pitting, grinding marks or disparity between tapers on the hubs and stub axles will reduce the coefficient of friction between the two components also the incorrect linear prelaod on the tapers due to incorrect assembly to achieve the correct pre load on the bearings will result in the reliance of the 'Key' having to transmit more torque than its design limits.
There are stress risers associated with the key way and is more likely to be a point of failure coupled with incorrect material specification or heat treatment if all is assembled correctly.
We have found that if the assembly of these items is carried out correctly to the correct specification the original design is capable, with good reliability, of transmitting 150 FT/LB of torque for a 900KG car on 550x16 Dunlop Racing and 200 Ft/Lb for a 750Kg car on 550x16 Blockley 5 std tyres. On these two examples we have 'Never' had a stub axle breakage or significant key way enlargement in 7 years.
www.bristolengineering.co.uk