Convertible
A potential drawback of convertibles is their reduced structural rigidity (requiring significant engineering and modification to counteract the side effects of almost completely removing a car's roof).
[2][3] The majority of convertible roofs are of a folding construction framework with the actual top made from cloth or other fabric.
[23] Optional air conditioning was gradually becoming more popular, and the availability of sunroofs and T-tops limited the appeal of the open body style.
[23] The popularity of convertibles was reduced by the increased travel speeds on roads (resulting in more wind and noise for occupants) and the emergence of more comprehensive vehicle crash safety standards in the United States.
[13][24] The market share of convertibles fell to two or three percent of total sales and the U.S. automakers discontinued the body style from their lineups.
Making convertibles on the assembly line was both expensive and time-consuming, thus not worth the problems needed to sell the limited number of cars.
[23] Specialized coachbuilders were contracted to make dealer-available cars such as the Targa top versions of the AMC Concord and Eagle "Sundancer" as well as the Toyota Celica "Sunchaser" as specialty models.
By 1955, the most popular materials were latex and butyl rubber fabrics that each accounted for around 35% of the convertible top's weight, with others included vinyl (12%), jute (8%), along with rayon and acrylic fibers (Orlon), amounting to about 1% each in the compositions.
[39] Designs that fold down to a lower stack height offer a smoother silhouette for the car with the top down while concealed side rails allow room for three passengers in the back seat such as on the 1967 Rambler Rebel convertible.
[41][42] These usually provide greater weatherproofing, soundproofing, and durability compared to fabric-based tops; some are available with integrated rear-window defrosters and windscreens.
During the 1950s and 1960s, detachable hard-material roofs were offered for various convertible sports cars and roadsters, including the 1955–1957 Ford Thunderbird and Chevrolet Corvette, as well as the 1963–1971 Mercedes-Benz W113 series of two-seaters.
Because the convertible top mechanism is itself expensive, the hard roof was customarily offered as an additional, extra-cost option.
On early Thunderbirds (and Corvettes through 1967), buyers could choose between a detachable hardtop and a folding canvas top at no additional cost, but paid extra for both.
The metal-framed "Carson top" was a popular addition for the 1930s Ford convertibles or roadsters because it turned these models into an almost instant hardtop.
[41] The design mimicked a convertible top, but lacking the bulky folding mechanisms enabled the removable hardtop to have a much lower and more rakish profile.
The benefits of improved climate control and security are traded off against increased mechanical complexity, cost, weight, and often reduced luggage capacity.
[citation needed] Folding textile convertible tops often fail to completely hide their internal mechanism or can expose their vulnerable underside to sun exposure and fading.
However, the cabrio-coach retains all bodywork to the top of the door frames and just replaces the roof skin with a retractable fabric panel.
[54] Produced by French coachbuilding specialist Heuliez, the Macarena's top can be folded in 60 seconds,[54] with a steel reinforcing beam behind the front seats incorporating LCD screens for the rear passengers into the crossmember.
No rear side windows and equipped with a soft top that can be raised partway, leaving the area above the front seats folded back.
