Classic-MG production used a mix of fastener standards through the years, UNF (Unified National Fine) for the bulk of post-war production, UNC (Unified National Coarse) on engine and chassis components, Whitworth and BSF on the earliest cars, and a creeping increase of metric fasteners as the production years moved into the 1970s and the BL parts-bin commonality with Rover and Triumph cars took effect. The Hardware section gathers the bolts, screws, nuts, washers and locknuts in the threads and head specifications that come up across classic-MG service and restoration work.
Thread Standards
UNF is the dominant thread standard across MGB, MGA, Midget and MGC production, used for the bulk of bodywork, suspension, brake and trim fasteners. UNC appears on heavier-duty applications where the coarse thread holds better in soft materials or under vibration, engine mounts, gearbox cases, some chassis components. Whitworth and BSF (British Standard Fine) appear on the earliest cars, the MG TD and TF, the MGA in its earlier specification, and the pre-war classics. Metric appears on later 1970s production where Rover and Triumph parts-bin items crossed into MG cars.
The Hardware section covers all of these threads in the head sizes used during production, hex heads in the BMC standard sizes, set-screws, cap-screws, countersunk machine screws and the various specialist fastener heads that come up.
Material Specifications and Finishes
Standard production fasteners were typically zinc-plated mild steel, the cheap, cheerful finish that does the job for several decades before the plating eventually fails and the underlying steel rusts. Stainless-steel fasteners are stocked for owners restoring cars where the original plated finish has failed and where the long-term solution is to move to a material that will not corrode. The trade-off is cost (stainless is more expensive) and torque tolerance (stainless threads are more prone to galling under high torque, so anti-seize compound on the threads is recommended for any high-torque application). Black phosphate and yellow zinc finishes are stocked for owners restoring cars to the period-correct visual finish where the original fasteners had a specific colour treatment.
Washers, Locknuts and Specialist Hardware
The supporting hardware covers the items that go with the fasteners, flat washers, spring washers, internal-tooth and external-tooth shake-proof washers, plain locknuts, nylock locknuts, and the specialist castellated nuts that take a split-pin retention. Where a fastener is being renewed, the matched washers and any associated locking hardware should be renewed at the same time, the small additional cost is dramatically less than the consequence of a fastener that comes loose in service. The technical team is available to advise on the right specification for any specific job, including the original-equipment matching for owners restoring cars to concours-correct finish.