Bond Minicar is a series of economical three-wheeled microcars which were manufactured by the British car manufacturer Sharp's Commercials Ltd (the company was renamed Bond Cars Limited in 1964), in Preston, Lancashire, between 1949 and 1966.
The basic concept for the minicar was derived from a prototype built by Lawrence "Lawrie" Bond, an engineer from Preston. During the war, Bond had worked as an aeronautical designer for the Blackburn Aircraft Company before setting up a small engineering business in Blackpool, manufacturing aircraft and vehicle components for the government. After the war he moved his company to Longridge where he built a series of small, innovative racing cars, which raced with a modest amount of success. In the early part of 1948, he revealed the prototype of what was described as a new minicar to the press.
Described as a "short radius runabout, for the purpose of shopping and calls within a 20-30-mile radius", the prototype was demonstrated climbing a 25 per cent gradient with driver and passenger on board. It was reported to have a 125 cc (8 cu in) Villiers two-stroke engine with a three-speed gearbox, a dry weight of 195 pounds (88 kg) and a cruising speed of around 30 mph (48 km/h). At the time of the report (May 1948), it was stated that production was "expected to start in three months' time". The prototype was built at Bond's premises in Berry Lane, Longridge where it is now commemorated with a blue plaque.
Sharp's Commercials was a company contracted by the Ministry of Supply to rebuild military vehicles. Knowing that the Ministry were ending their contract in 1948, and recognising the limitations of his existing works as a base for mass production, Bond approached the Managing Director of Sharp's, Lt. Col. Charles Reginald 'Reg' Gray, to ask if he could rent the factory to build his car. Gray refused, but said that instead, Sharp's could manufacture the car for Bond and the two entered into an agreement on this basis. Bond carried out some further development work on the Minicar, but once mass production was underway, left the project and sold the design and manufacturing rights to Sharp's.
The prototype and early cars utilised stressed skin aluminium bodywork, though later models incorporated chassis members of steel. The Minicar was amongst the first British cars to use fibreglass body panels.
Though retaining much of Lawrie Bond's original concept of a simple, lightweight, economical vehicle, the Minicar was gradually developed by Sharp's through several different incarnations. The majority of cars were convertibles, though later, hardtop models were offered, along with van and estate versions. Minicars were generally available either in standard or deluxe form, though the distinction between the two was largely one of mechanical detail rather than luxury. The cars were powered initially by a single-cylinder two-stroke Villiers engine of 122 cc (7 cu in). In December 1949 this was upgraded to a 197 cc (12 cu in) unit. The engine was further upgraded in 1958, first to a single-cylinder 247 cc (15 cu in) and then to a 247 cc (15 cu in) twin-cylinder Villiers 4T. These air-cooled engines were developed principally as motorcycle units and therefore had no reverse gear. However, this was a minimal inconvenience, because the engine, gearbox and front wheel were mounted as a single unit and could be turned by the steering wheel up to 90 degrees either side of the straight-ahead position, enabling the car to turn within its own length.
A method of reversing the car was offered on later models via a reversible Dynastart unit. The Dynastart unit, which doubled as both starter motor and dynamo on these models incorporated a built-in reversing solenoid switch. After stopping the engine and operating this switch the Dynastart, and consequently the engine, would rotate in the opposite direction.
The car proved popular in the UK market, where its three-wheel configuration meant that it qualified for a lower rate of purchase tax, lower vehicle excise duty and cheaper insurance than comparable four-wheel cars. The three-wheel configuration, low weight and lack of a reverse gear also meant that it could be driven on a motor cycle licence.
In April 1962 the purchase tax rate of 55 percent, which had been applied to all four-wheeled cars sold in the UK since the war was reduced to 45 per cent. In November 1962, it was reduced by another 20 per cent to 25 per cent – the same rate as that applied to three-wheelers. This rapid change meant that at the point of sale, some three-wheelers became more expensive than four-wheeled cars like the Mini. In response, Tom Gratrix, head of Sharp's sent a telegram to the Chancellor warning that unless a similar tax cut were given to the purchase tax rate for three-wheelers, there would be 300 redundancies and possibly the closure of the Sharp's factory. No cut was forthcoming, sales of Minicars declined rapidly from this point and the final Minicar was produced in 1966. At the end of production 24,482 had been made.
Sold as the Bond Minicar (the Mark A suffix being added only after the Mark B was introduced), the car was advertised as the world's most economical car. It was austere and simple in design, without luxuries. Production began in January 1949, although 90 per cent of the initial production was said to have been allocated to the overseas market.
As with the prototype, a large proportion of the Minicar was made from different aluminium alloys. The main body was a very simple construction of 18 swg sheet with a 14 swg main bulkhead. The integrity of the main stressed skin structure was enhanced by the absence of doors, the bodysides being deemed low enough to be stepped over without major inconvenience (unless you were wearing a skirt). Most of the bodywork panels were flat or fairly simple curves whilst the compound curves of the bonnet and rear mudguard arches were pressed out as separate panels. The windscreen was made from Perspex. The car was alleged to weigh only 308 pounds (140 kg) “all-in” or 285 pounds (129 kg) dry and its light weight was regularly demonstrated by one person lifting the entire rear end of the car off the ground unaided. A test run between Preston and London at an average speed of 22.8 mph (36.7 km/h) gave an average fuel consumption of 97 mpg‑imp (2.9 L/100 km; 81 mpg‑US) for the journey.
The car had a single bench seat with a small open compartment behind suitable for luggage. There was also a fold-down hood with detachable sidescreens. The headlights were separate units mounted on the side of the car, though of such low output, they have been described as providing "more of a glimmer than a beam". At the rear there was a tiny, single, centrally-mounted lamp.
The air-cooled Villiers 10D 122 cc (7 cu in) engine had a unit construction three-speed manual gearbox without reverse. This had an output of 5 bhp (4 kW; 5 PS) at 4,400 rpm which the manufacturers claimed gave a power-to-weight ratio of 49 bhp (37 kW; 50 PS) per ton unladen. The engine unit sat in an alloy cradle ahead of the front wheel, together forming part of its support. Both front wheel and engine were sprung as part of the trailing link front suspension system, which was fitted with a single coil spring and an Andre Hartford friction damper. The rear wheels were rigidly mounted to the body on stub axles with suspension provided by low pressure "balloon" type tyres. Starting was achieved by using a pull handle mounted under the dash panel and connected by cable to a modified kick-start lever on the engine. The steering comprised a system of pulleys and a cable usually referred to as "bobbin and cable", connecting a conventional steering wheel to the front steering unit. The bobbin and cable steering arrangement was replaced by a rack and pinion system in October 1950. Brakes were provided on only the rear wheels; they were conventional drum brakes operated by a system of cables and rods.Early on, Sharp's adopted a policy of continual gradual upgrading of the Minicars, either to simplify or reduce maintenance, to redress noted failings or to improve some aspect of performance. Such changes were usually made available as kits to enable existing owners to upgrade their own cars retrospectively.
In December 1949, a Deluxe version was added to the range. This has a Villiers 6E 197 cc (12 cu in) engine, which had an increased output to 8 bhp (6 kW; 8 PS) and a power-to-weight ratio of 51 bhp (38 kW; 52 PS) per ton. There were also a number of modest refinements including a spare wheel and a single wing mirror. The manually operated windscreen wiper fitted on the standard car was upgraded to an electric Lucas type. Although this was found to damage the original perspex windscreen, it was not replaced by a Triplex Safety Glass screen until the introduction of the Mark B in 1951.
A Bond Minicar Deluxe tested by The Motor magazine in 1949 and carrying only the driver had a top speed of 43.3 mph (69.7 km/h) and could accelerate from 0-30 mph (48 km/h) in 13.6 seconds. A fuel consumption of 72 mpg‑imp (3.9 L/100 km; 60 mpg‑US) was recorded. The test car cost £262 including taxes.
Towards the end of 1949 (as unveiled and demonstrated in October at the Motor Cycle Show at Earls Court, London) an optional mechanical reversing device became available which comprised a long lever with a ratchet and a hexagonal socket on the end which fitted onto the centre of the driver's side rear wheel hub. This device could then be operated from the driving seat and allowed the car to be cranked backwards by hand to assist with maneuvering.
Progressive development of the Minicar and Minicar Deluxe continued until the more significant introduction of coil sprung independent rear suspension and the much-needed Triplex Safety glass windscreen. (The Triplex windscreen was subsequently offered by Sharp's Commercials as a retro-fit kit for the earlier Minicar.) This provided an ideal opportunity to relaunch the car as the Bond Minicar (Mark B) in July 1951.
Much of the design work for the Mark B, in particular the rear suspension, was carried out by the engineer Granville Bradshaw. Bradshaw had become involved with the Minicar at the invitation of his brother Ewart Bradshaw, the chairman of Loxhams and Bradshaws Group of which Sharp's Commercials was a subsidiary.
The rear suspension system was of the sliding pillar type, a block carrying the stub axle rode up and down on two guide pillars mounted on a solid casting bolted to the side of the body. The block's vertical movement was controlled by coil springs. The front suspension was upgraded with a hydraulic shock absorber
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