Built in 1951, this was a very basic and
simple utility three-wheeler which shared several common features
that were already being developed for the Mark C. The broad outline
of the design specification was to meet two criteria: The first
was to build a service vehicle that could either be used to transport
dry goods around at docks and development sites or to pull luggage
trains at railway stations and airports. The second was for an invalid
carriage capable of carrying a wheelchair that would comply with
the regulations set out by the Ministry of Pensions.
As
with the Mark C, the main centre section of the stressed skin aluminium
body obviously had its origins with the Mark B. The curved Triplex
glass windscreen sat on a full width dash incorporating the cubby
hole and the curved bulkhead extended towards the bonnet. Moving
forwards, the front end also bore more than a passing resemblance
to a Mark A or B although the styling changes were more radical.
The externally hinged bonnet was the same depth but a much squarer,
flatter front end replaced the rounded type. The vertical body sides
followed the bonnet profile and then turned a 
corner to present a flat vertical front.
In the centre was set a square grille divided down the middle with
more upright slats on either side. Underneath the grille was a full
width bumper which also carried the number plate. Although not shown
in the picture on the sales brochure cover, a pair of "Butler"
or "Lucas" type headlamps at the front corners were mounted
on a sort of vertical tube arrangement which went through the front
bumpers and were then secured at the bottom. Behind these mounting
tubes was a feature definitely unlike any Mark A or B. Between the
rear of the bumper and a point in line with the back of the bonnet
and extending upwards nearly to the bonnet was a large rectangular
bulge - one on each side of the body. The need for these unusual
bumps becomes apparent when it is realised that the Sharp's Commercial
had the same newly designed worm and sector steering arrangement
as the Mark C. Without these, the front of the engine when using
the 180o steering lock obviously fouled the two
body sides. (Of course, the Mark C overcame the same problem by
the introduction of the front wings on either side of the bonnet.)
The rear body contrasted to the Mark A or B, although it did use a pair of the smaller Mark B type rear wings to cover the wheels. Moving rearwards from the base of the windscreen, BOTH sides of the body had large square cut-outs (but no doors) for gaining access to the interior. These did not extend completely down to floor level, but stopped approximately 6" short. The rest of the body continued to just behind the-rear wings where it then turned the corner, but instead of sloping inwards like the Mark A or B it remained vertical. This gave the boot area behind the driver an enormous 25 cu. ft. carrying capacity. (Having a vertical rear boot panel was exactly the same idea that was used on the later Minitrucks, but the Sharp's Commercial pre-dates the earliest Minitruck by approximately six to nine months.)
Because of the two large cut-outs in the body sides, to stop the vehicle folding in half required a large amount of strengthening. Under the floor, a steel girder backbone and a steel crossmember between the rear wheels formed a "T" shape to look after the main body bracing. Internally, the floor was further braced in the rear by a triangular box member whilst at the front - below the windscreen and at the front corner of the "door" aperture - triangular gussets between the sides and the floor helped to prevent the body twisting.
The interior by the very nature of the
work that it was intended to be used for was very spartan. Bodysides
and the front floor were covered with "Hardura" plastic
coated felt, whilst the rear boot floor comprised nothing more than
wooden slats. A centrally positioned front seat consisting of a
single pressing covered with foam rubber was mounted on short coil
springs to give the driver a small degree of comfort! All the pedal
controls were conventionally laid out and starting was by the usual
manual operation. It was the steering wheel and gearchange lever
that departed from the normal Minicar position. Both of these were
mounted centrally on the dash with the gear lever positioned, unusually,
to the right hand side. The speedometer was set in the dash opposite
the cubby hole and rear vision was by a single mirror fixed vertically
on the outside of the bulkhead, also offset to the right.
Mechanically, the Sharp's Commercial was almost identical to the Mark C. It too had three-wheel braking but used the same adjustable coil spring rear suspension as that already fitted to the Mark B. The front bulkhead, 180o worm, sector and downtube arrangement was exactly the same as the Mark C but with a few notable differences:
The motive power came not from the familiar
Wolverhampton-made Villiers two stroke unit but from a 250 cc side-valve
four stroke engine made by Brockhouse Engineering of Southport.
This was mounted on top of an Albion gearbox providing three forward
gears and a reverse. As the driving sprocket on this type of gearbox
was on the right hand side, (Villiers were always on the left) the
tubular trailing arm and front hub mounting was reversed to that
of the Mark C, i.e. the trailing arm pivoted on the right hand side.
(Notice the picture is almost identical to the Unicycle with the
exception of the fuel tank mounted above the cylinder head.) The
Brockhouse and Albion combination was claimed to give the Sharp's
Commercial a top speed of 40 to 50 m.p.h. even when fully loaded,
whilst still returning 70 to 80 m.p.g.
Announcement of the Sharp's Commercial 3 Cwt. was made at the 1951 Motor Cycle Show where it was also displayed on stand number 70 alongside the new Mark C and the Motorised Unicycle. The price was stated as being £199 10s 0d plus £56 3s 4d purchase tax making a grand total of £255 13s 4d (£255.67p). The vehicle on display had a yellow body and black rear wings. Shown with the open utility type body, the publicity material talks about later models having detachable hoods or even van bodies. It also suggests that it would be "ideal as a factory runabout, a light delivery tuck, an airfield dispatch carrier or as a general runabout for garages, haulage contractors and agricultural representatives."
Fortunately, researching this vehicle was made easier by being able to discuss various points with Mr. Steve Driver who worked on this prototype as well as the early Mark C's. It appears only the one vehicle was ever built and even that was never completely finished properly. Mr. Driver informed the Club that the vehicle was regularly driven with a housebrick at the side of the driver's seat because the handbrake mechanism was incomplete and the only way to keep it on was to wedge the brick underneath it!
The unusual single front seat arrangement was apparently for two reasons: Firstly, without a second seat the goods carrying capacity was greater and a larger space was available. Secondly, it had many advantages when submitting a design to the Ministry of Pensions for use as an invalid carriage. Sharp's Commercials had already tried unsuccessfully to gain Ministry approval with conversions to the Mark A and Mark B. The Sharp's Commercial went a long way to meeting the regulations for ease of entry for a disabled person, ability to stow a regulation standard-size wheelchair in the rear, designed for one person only, easily converted to hand control operation, economical to run and reasonably cheap to buy. Why it never progressed beyond the prototype stage can only be guessed at.
