Closing the VW debate, a person who has lived in Germany and owned and drove various Beatles from 1962 onward, offered this explanation to the hex sizes myth. In the olden days, it was common among German manufacturers to sell cars with a set of wrenches and other tools included. The Beatles, inexpensive as they were, came with only two open-end wrenches, one with 8 and 10 ends, the other with 14 and 17 (or similar), and with one tubular wrench with two sizes. Thus 6 sizes altogether. In addition, there was a double-sided screwdriver, one end flat, the other Phillips. VW may have been so skimpy for two good reasons: (1) To support the reliability myth (marketing claim of no need of repairs), and (2) to cut cost. Concerning repairing the Beatles with these tools, these tools were for all MAINTENANCE, not for taking the car apart or assemble it, nor for repairs unless those tools happened to fit a specific task regardless.
In case you'd like a confirmation of your skill in identifying the metric wrench size, here is the solution: M4 (+1/2+1)=7 M6 (+1/2+1)=10 M8 (+1/2+1)=13 M10 (+1/2+1)=16 M12 (+1/2)=18 M16 (+1/2)=24 M20 (+1/2)=30 This relationship between the thread and the hex size assures ~equal stress in the stem as under the head (or nut), i.e. max. utilization of material. Stan J.
