There are a number of unusual things about Ford’s 1931-32 Convertible Sedans, starting with the fact that Ford didn’t design them.

When the 1928 Model A was designed, the Ford Motor Company was still years away from opening its own dedicated styling department. As a result, the Model A’s exterior design was a collaborative effort that included Edsel Ford, Ford body engineer Joseph A. Galamb, Briggs engineers, and Amos Northup, chief stylist for the Murray Corporation.  (Briggs Manufacturing and Murray were Ford’s chief body suppliers at the time.) But ultimately, the Model A’s look was largely the vision of Edsel Ford, who scaled down his favorite Lincoln styling elements to suit the smaller proportions. To this day, the Model A is often called a “baby Lincoln.”

From there, numerous body styles were altered or added over the Model A’s four-year production run, the last of which was the Convertible Sedan introduced in May of 1931. The primary contract to produce the bodies was awarded to the Murray Corporation, and naturally, the task of designing the new deluxe body style was assigned to Northup, already an accomplished stylist. (See our feature on Amos Northup here.)

While Ford called Northup’s design a convertible sedan, it wasn’t like any of the other convertible sedans then on the market. First, it had only two doors rather than four. This greatly improved body rigidity, as the four-door open bodies of the time were relatively flexible and prone to squeaks and rattles, especially on smaller cars. Next, the front door glass frames were fixed to the doors and the rear quarter glass frames were part of the body shell. This also added rigidity to the structure by creating a long top rail, and it provided better all-weather protection.

Meanwhile, the top section folded back for fresh-air motoring, as in any open car. For a smaller platform like the Model A, Northup produced an ingenious solution. “The upper structure is a new development in convertible car construction,” Ford declared. “This eliminates entirely all rattles and similar noises that have caused dissatisfaction with other convertible designs.”

As the most expensive standard offering in the Model A lineup for 1931 at $640, the Convertible Sedan got the full De Luxe treatment with cowl lamps, a left fender-mounted spare tire, chrome windshield frame, carpeting, and crush-grain leather upholstery in Deep Tan. But apart from the bodywork, the Convertible Sedan was a Model A through and through, with the standard 40-hp L-head engine and 103.5-in wheelbase chassis with transverse leaf springs front and rear. While Ford’s official designation for the body type was 400-A, Model A experts and enthusiasts generally refer to it as A400.

Considering the late introduction, the Model A Convertible Sedan sold reasonably well at just over 5,000 units, and the body style, now called B400, was adapted to the slightly larger Model B and Model 18 V8 for 1932. (Above and below.) There was now a choice of two interiors, Brown Bedford Cord or Brown Leather. However, the Convertible Sedan sold in considerably smaller numbers in ’32, fewer than 900 cars. The unusual body style was discontinued, and Ford would return in 1935 with a more conventional convertible sedan.