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a better chassis for the body makers
by Paul Brockington IF chassis makers catered more for van builders, the job of providing the user with the kind of body he required at an acceptable cost would be radically simplified, according to technicians of Wilsdon and Co Ltd, Solihull, West Midlands.
The obtrusion of chassis components into the area which the bodybuilder considers should be reserved for the superstructure could be avoided by the chassis-maker without costly redesign or modification, although, in specific cases, this may be debatable. But the chassis could be modified at little extra cost.
Clutter of components is one of many problems which the bodybuilder has to contend with. Body-mounting recommendations are frequently non-decisive and, of special importance, affording adequate body-load restraint at the front end is typically frustrated in one way or another.
In the Wilsdon view, bodyload restraint should be a priority consideration in the interests of safety. Obstacles to providing it include chassis frame members which are cranked too acutely, obstructions on the outside of one or both members which may make it impossible to bolt on reinforcing bulkhead stanchions which Wilsdon regards as an essential safety feature on most vans. Modifications which are necessary on this count have to be compatible with those required to overcome 'body location difficulties derived from obtrusion above chassis level of, for example, a crossmember, air cleaner, brake servo or battery box. To locate the stanchions appropriately and/or to mount the body in the best possible position, these modifications could include re-routeing air-cleaner pipe connections and mounting the air cleaner in a different place, increasing the gap between the cab and the body or raising the floor level.
Weight problem
Moving the body back usually creates a weight distribution problem and mounting it at a higher level would be unacceptable to an operator who had stipulated a low floor with wheel arches.
In the Wilsdon view, too little regard has been paid by bodybuilders and operators to the safety aspect of body load restraint in a van.
The danger of a load shifting and hitting the cab when a platform truck is braked hard, and the greater danger of injury to the driver in a head-on impact, have been acknowledged over the years by safety-conscious associations and individual operators.
It has generally been assumed that a shifting load is less likely to be a hazard in a van, even if the load can move as a unit and if the bulkhead is the only farm of load restraint provided apart from floor friction.
But although the hazard is reduced by containing the load in a van body it can still be a very serious one, the more so because an insecure load is less likely to be recognised as such than it would be if it were being carried on a platform vehicle.
Moreover, high loads are normal to van operations, and impact high on the bulkhead can be more destructive than a force applied lower down. In the absence of multiple load restraints in the body, providing a sufficiently robust bulkhead is the only safety option. U-bolt mounting is claimed by Wilsdon to be quite inadequate and conventional mountings are unacceptable unless there are multiple load restraints.
Elaborating on methods of stanchion mounting, Wilsdon points out that spreading the attachment area and bolt locations is normal practice with large bodies, although this exacerbates access-to-web difficulties and may necessitate temporary removal or permanent repositioning of a fuel tank, air reservoirs and so on.
While modifying a body or its mountings to accommodate a protruding gearlever, cross member or other component by raising the floor level (if acceptable) locating the body to the rear of its normal position or by recessing the structure is a straightforward exercise, it adds to cost and, if the chassis is not a known type, to the planning time.
Typically, the brake pipes and electric cables are mounted centrally on the inside of a chassis member web or are spread out and have to be re-routed along the bottom flange to enable the body to be attached to a chassis. Surely, says Wilsdon, this could be done by the chassismaker at no extra cost. It would be welcomed by all van builders.
Mercedes-Benz, says Wilsdon, is the outstanding example of a chassis-maker who shows awareness in a practical way of bodybuilders' problems, notably by providing mounting brackets on all nontippers in the company's range.
Although the Ford code of body practice is regarded as good it doesn't go far enough. If it is not convenient for brackets to be fitted in the factory, holes should be drilled to accept brackets. Having made a good start with special vehicle options (SVO), Ford could have been leaders of the field, according to Wilsdon, in easing the prob-, lems of bodybuilders.
Spares location
Spare wheels are often "located in diabolical places," in the opinion of Wilsdon staff, a particular example of this practice being the Bedford CF on which the spare is housed at the rear in the centre.
Equipping the van body of a CF with steps involved changing the position of the spare. And the CF is not an isolated case of misguided location of the spare.
A number of chassis originally designed for application to platform trucks are now mainly supplied to van builders without modification, and such vital procedures as filling the fuel tank and topping up the battery are virtually impossible if a conventional van body is fitted to the chassis. In the notable case of the British Leyland FG chassis, models were delivered with vertical filler pipes which could not be accommodated in a vehicle with a van body. Reacting to Wilsdon's insistence, a suitably modified filler pipe for vans was later included in the available optional equipment.
As a sign of the times perhaps and a regrettable one in the Wilsdon view, rear onepiece light clusters are now too costly, too big and too difficult to house, and with the exception of the bulbs, damage to any part of the cluster reduces the whole unit to scrap. Moreover, a cluster is very easily damaged in the workshop as well as in service.
Tribute is paid by Wilsdon to the progress made by specialist manufacturers of load-retaining devices and to the variety of load-control devices that have been developed. But it is emphasised that the efficiency of any loadretaining system may well depend on whether the body is properly secured and robustly built.