Cars 2, Mater, and Whitworth

When the movie Cars 2 hit theaters a few weeks ago I had to go and see it. Being a car guy, of course I had to go see a movie called Cars anything the first day it was in theaters. I also don’t mind saying that my kids were not with me. I did the same thing when the first Cars movie was released. No sense in taking the kids and run the risk of ruining my enjoyment. The movie itself was great and I enjoyed it very much as a movie goer but also as a car guy.

Like the first Cars movie there was a great deal of jokes, gags, and visuals that only a car guy would fully understand but one plot point in Cars 2 was so specific that I’m sure that I was the only one in the theater that really understood it.

As many of you know there used to be a rule when you were working on a car that said that if the car was American: Chevy, Ford, Dodge, Jeep, then you used standard tools on all of the nuts and bolts, and if the car was foreign: Honda, Toyota, Volkswagen, BMW, then you used metric tools on all of the nuts and bolts. This is not true anymore and really hasn’t been true for about 25 or 30 years. All cars in the US have metric fasteners almost exclusively. Once in awhile you might still find something standard on an American car, but it’s pretty rare. My screen name metricwrench comes from the fact that I am a mechanic that works on cars so I primarily use metric wrenches. Isn’t that clever?

Anyway, standard tools are those that show measurements in inches and fractions of inches. 1/2”, 5/16”, 1 1/8”, are examples of this. These labels on the tools refers to the size of the head of the bolt but having a head that measures in inches like this means that the diameter of the shaft of the bolt and the size and pitch of the bolt threads will also follow this standard.

The name “Standard” actually refers to what is officially called the American Standard Units which are essentially a copy of the old British Imperial Standard but some of the exact numbers vary a bit. These units, such as inches and feet, have been around since the early 1800’s and are not used much by the British anymore. They have officially adopted the Metric System but we stubborn Americans have not, not that it really matters that much.

Metric tools come in sizes ranging in millimeters usually starting at about 4mm and going up from there. Some common metric sizes that are used on cars are 10mm, 12mm, 13mm, 19mm and many more. Metric tools are sized for the heads of the bolts and for the nuts and like the standard fasteners, the real difference is in the width of the bolt shaft and the pitch of the threads.

Metric tools are easier to get used to because if you grab a 13mm wrench and it’s a bit too small then you know what the next size up is going to be. With standard tools if you grab a 5/16 wrench and it is a bit too small you can’t easily tell what the next size up will be unless you are an experienced mechanic. Just so you know the next size up is 6/16 but it won’t be labeled as such, do some simple math to figure out how it will be labeled.

So what does all of this boring stuff have to do with Cars 2 and Mater. Well, there was actually a third system or standard, but this standard of measurement applied strictly to fasteners, meaning the size of a bolt shaft, threads, and heads. This standard is known as Whitworth. In the 1800’s Whitworth was developed by an engineer named Joseph Whitworth in Great Britain. Whitworth bolts and nuts are not used anymore and have not been used for some time, but any mechanic who has worked on any old British cars may have come across some Whitworth fasteners.

An old MG made in England that likely has Whitworth nuts and bolts

As Mater says in Cars two, “they ain’t metric, they ain’t inches, you never can find a wrench to work on them”. Whitworth bolts are used on the engine in the photograph that Mater, that they assume will lead them to the bad guy. Just as some metric and standard sizes are very similar, some metric size and standard size wrenches fit on Whitworth bolts, but sometimes not well enough to work effectively. This is why at the end of the movie when Guido is trying to remove the bomb from Mater he can’t because he doesn’t have the right socket size to remove the bolts holding the bomb to Mater’s engine.

The other part of all this is that the bad guy, Miles Axlerod closely resembles a Land Rover which is a British car, therefore he would use Whitworth bolts, and most of the old British cars that used Whitworth bolts in the past were, and are considered to very unreliable and prone to break down. Just like all the bad guys in the movie were lemons. The best quote of the movie regarding British cars comes from Mater when he is talking about how much oil British cars leak, “If a British car ain’t got oil under it, it ain’t got oil in it.” of course this whole British cars are lemons theme doesn't reconcile very well with the fact that the character Finn McMissle, who was a good guys, closely resembles an Austin Martin DB5 which is an old British car. 

The cars from Great Britain today are not like the ones from the past in that they are not the lemons that they once were but it takes awhile for a reputation like this to die. Not only that, but in the movie most of the cars that where part of the evil plot and were considered lemons were made by companies that are not around anymore. Things like the AMC Pacer, and Gremlin, the old British cars, and there were even a few old communist cars from Eastern Europe if I’m not mistaken. I could think of a few cars that are still on the road today, or are still for sale at dealerships today that they could have put into the movie, but I’m sure that the lawyers would not have allowed it.

So all the jokes about Whitworth from Cars 2 refer to an outdated standard for nuts and bolts, and more specifically a standard that was last used on old British cars. So how many people in the theater really understood the joke? If they have experience working on old British cars then they will get it. Probably not too many others will, but I think people will understand just enough to still enjoy the movie.