X-Frame

The more I research the more I believe that I am correct and here is why. Many references to the Rover car company history state that they first decided to enter the motor car business on December 16, 1903 and revealed their first prototype on July 11, 1904. By this time Phelps was already building and selling cars. Even though Rover clubs and books state they invented the backbone chassis this can't be true since the Phelps, even if it was limited production and short-lived, was actually the world's first unless someone finds different? There is also a patent for Phelps' backbone design registered in 1903 and ads for sales in late 1903 while Rover didn't start selling until December 1904.

BTW, his business partner Elliot Cabot Lee (1854-1920) was once the president of the Automobile Association of America. When Phelps left abruptly, Lee didn't have a car to sell and changed the company name to Courier Motor Co. in 1905 but never made any cars under that name (there was another company named Courier in Ohio around the same time). Then he started the Shawmut Motor Co. which made cars from 1906-1908.

I didn't see a forum for brass era cars so posting here. Many books and references cite the British 1904 Rover (designed by Edmund Woodward Lewis 1870-1941) as the first vehicle utilizing a backbone frame (think Tatra style) but I have run across another vehicle released a year earlier made in Stoneham, Massachusetts (USA) as the Phelps Motor Vehicle. The body tilted up to access the mechanics and was a car built to order. The founder Lucius Joshua Phelps (1850-1925) was an enigma. Phelps was an inventor and his business partner a lawyer. The cars were not advertised, expensive, and sold in Boston. One car ran an endurance race and won two gold medals. But all of a sudden, Phelps upped and abandoned the company in 1905 to get out of the automobile industry. He was a world traveler and in 1925, left from his son's house in NJ to NY to board a train and vanished never to be heard from again. Does anyone know how many Phelps cars were built between 1903-1905? And since Rover did not introduce their cars until December 1904 and Phelps in January 1904, I would say Phelps was the first backbone frame vehicle unless you know of an earlier vehicle (other than horse drawn wagons)? Eric

Thanks, Roger. Possibly the repair shop used an aftermarket fender or hood and not one from the factory or from an original parts car? Aftermarket panels are notorious for not fitting properly unless there is some alignment issues with the cowl from the accident? I am noticing the rear being up higher than normal... air suspension?

Roger, congratulations. This is one of my favorite year and model as well as color combinations. Low mileage, still have the correct original whitewalls. But you have a sharp eye obviously with your 1/12 scale cars like me having managed auto detailing for major dealerships many years ago. My concern is where I circled on your photo... where the hood meets the door. There is a fit and finish issue and since the paint shade does seem to be off on the fender and hood, possible a fender bender in the past occurred and the new fender is not a good fit (alignment)? There should not be a big gap there but tight. Examples attached as well.

1940 Cabriolet Chassis Question... I am new here but have been gathering information for an academic book on the design and development of vehicle chassis for the past 9 years. The '40 Convertible fame has been a puzzle for me and hope historians or those who own them can help solve this one? We know that there was no 1939 Convertible offered in the states but there was one exported to Australia. The frame had a conventional X brace added to it by Holden prior to assembling the kits. The '40 models were also delayed. The chassis design is a one year, one model only design not shared by any other GM line and is a bit awkward and overbuilt. Even though GM had been using some form of X bracing since 1933 and even Chevrolet used it on their 1935 Standard models (another one year only frame). It is known that Marvin Coyle "Mr. Facts and Figures" was a penny pincher and as soon as he took over the Chevrolet helm, ordered the new KY design frame to be redesigned since it was costly in many ways to produce. So, why was this massive one year only tooling allowed? The frame is not mentioned in any sales materials. Not even shown in shop manuals. I have only run across one body shims chart from a service bulletin and the layout is not 100% of what the production version ended up. I did find a mention in the 1941 Chevrolet Engineering book about how this design was a failure and the new 1941 frame, which is basically a traditional X braced style, was much stronger. Something they could have utilized in 1940 but didn't... why? Who designed this frame? Who authorized it? And why was this particular oddly laid out design chosen over tried and true X bracing other GM cars were already using? Thanks for any information! Eric Photo from Bob Johnson's online collection

Want to bring this topic back up and hope new members may have something to contribute. I can add that the new London Taxi TX5 is a unibody car and so, the TX4 was their last to use an X frame configuration. Now, are there "any" cars (or trucks) being made, worldwide, that still uses a cruciform or X braced chassis frame? Thanks!

1907 Imperial double-drop still being used on vehicles today

A tech question hoping someone here may be able to add to this? The double-drop chassis frame design has been a standard part of vehicle technology since the 1930s but dates back much earlier. Supposedly, the world's first car to use it was the 1907 Imperial (not Chrysler) from Williamsport, PA. But prior to that, there was the single-drop design which the 1905 Peerless is credited again in the USA. I found an earlier version with the UK 1904 Wilson-Pilcher. Does anyone know of even an earlier version of the single (or even double) drop frame?

CY is the manufacturer UD is the tire size F317 is the tire type / model 19 is the week of the year 5 is the year Since tires have shelf life, no one would be expecting to figure 20+ years later what year it was made

Where did you come up with 1971? The last digit in these DOT codes is the year and it is a '5'. I wasn't sure about when the lettering code changes before 2005? Thanks.

It's a McCreary tire P315/45 16 possibly made the 19th week in any year with a 5 in it such as 2005, 1995, 1985, 1975 Hard to tell.

Does anyone have a high resolution scan of this Zephyr X-ray illustration that you can share? Thanks.

Actually, Chevrolet used this chassis layout from 1934-1936 (only on the Master in 1936) and Pontiac also used it the same years. Not an "X" but is called a K-Y frame yet functions the same way. Chevrolet went to the boxed girder ladder frame in 1937 (1936 on the Standard model) and Pontiac went with a more traditional X braced frame in 1937. Chevy played with a X brace ladder frame on the 1935 Standard model, one year only. And the 1935 Pontiac Deluxe had a different frame which was a cross between the K-Y and X. Would like to find the original photos of this to get a scan.