Classic Refuse Trucks DEMPSTER

Dempster in the late 1950's

"The nearest thing to automation in the rubbish collection field" is how Dempster described their new 1957 Dumpmaster front loader. Though similar in principle to the original 1955 edition, this machine was so new and so advanced that it is somewhat astonishing how quickly the firm developed it. The new Dumpmaster was the result of a collaboration between George R. Dempster and an engineer by the name of William R. Herpich. Herpich was responsible for the Hydro E-Z Pack side loader built by Hercules Galion, which was one of the first heavy-duty, all hydraulic side loaders on the market. Accordingly, the 1957 Dumpmaster packer body is based on a very similar concept with a top loading bay and full-travel packer panel powered by a double-acting telescopic hydraulic cylinder. In fact, the use of this type body on a front loader is arguably a more practical application since manual loading height was not a factor. The heavily reinforced body supported packing pressures of up to 58,000 pounds, more than twice that of the old mechanical Pak-Mor body. The result was a claimed 3:1 packed volume reduction, giving the Dumpmaster an unprecedented range of operation before unloading was necessary.

If this were not impressive enough, Dempster and Herpich completely redesigned the lift mechanism and container coupling, creating a new industry standard. Like previous front loaders, the lift arm pivot axis was near the lower front section of the body, just behind the cab. But instead of straight, horizontally inclined arms as before, the new arm rose vertically to a point above the vehicle cab and then curved forward and dropped again just ahead of the font bumper. This "curved arm" completely cleared the vehicle cab door area and rear view mirrors during all phases of the loading cycle, eliminating a major safety hazard to the driver, as well as doing away with the need for retractible mirrors. It was perhaps the single greatest advance in front loader technology of all time, and has been imitated ever since. As a side benefit, the vehicle could be safely maneuvered and even driven with the arms in the lowered position.

The third major change on the new Dumpmaster was in the container coupling and dumping method. Instead of the claw and stud method, coupling was now achieved with a set of forks. Fork coupling had already become the standard of west coast front loaders, which used a set of flat forks engaging slots in the bottom of the container. Dempster's new method set the forks on edge and moved them to the outboard ends of the loading arm assembly to engage shallow pockets welded to the sides of each container. These new "side forks" gave the driver a much better view of the coupling during hook-up. The side pocket slots were also far less hazardous to pedestrians than the studs of the 1955 Dumpmaster container, which protruded from the containers at eye-level. The forks were affixed to a rock shaft connecting the ends of each lift arm, which was pivotable by a pair of cylinders allowing pitch control of the container and full inversion once over the loading hopper. This pivoting shaft method was first used on the short-lived Cook Brothers front loaders and soon became standard on virtually every front loader design.

Those who still preferred the old Dumpster System, and used it with transfer trailers could now order a Dempster-built compaction trailer, a high capacity unit with full travel hydraulic packer-ejector panel. Coupled with a GRD hoist on a short wheelbase truck, it added up to an efficient satellite system which found favor in communities large and small for many years to come. Added to this lineup was the all new Dinosaur roll-off system, and by decade's end Dempster was the undisputed leader in detachable container refuse storage and disposal systems in the nation. It is an amazing feat for a firm that was mostly one-dimensional in 1950, when development of the rear loader was the focus of much of the refuse body industry. By addressing problems associated with commercial & bulk refuse disposal, and coming up with innovative solutions, Dempster was able to grow into an industry powerhouse while Leach, Heil and Gar Wood mostly battled over rear-loader supremacy. Though the Leach had come out with a decent container system for the rear load Packmaster, it paled in comparison to the broad range of products offered by Dempster at decades end. Other popular rear loaders were somewhat clumsy when adapted for container work (such as Roto-Pac) or even completely unsuitable, as was the the case with Gar Wood's popular Load-Packer 200.

The all new look of Dempster in 1957 (clockwise from top) A Dinosaur hoist hooks up and loads a 35 cubic yard container: New Dempster compaction trailer is fed by a truck mounted GRD-304 F2 high lift hoist handling a Dumpster container; The revamped Dumpmaster front loader

With innovate products appearing across the country, it's easy to see how the Dempster name became synonymous with refuse containers. George R. Dempster further cemented this association, when in 1959 he appeared as a contestant on The $64,000 Question, a nationally syndicated game show. In a previous episode of the show, a sanitation worker had been a contestant, and had mentioned that he drove a Dempster Dumpster truck for a living. The host remarked jokingly that the show typically received a sample of any product mentioned on the show, but in this case they didn't expect anything. George Dempster heard about the remark, and showing a keen sense of humor, had one of his Dumpster containers delivered to the host's front lawn! Dempster was himself then invited on the show, appearing over several weeks time and accruing winnings of $32,000 before voluntarily withdrawing from competition. He was perhaps the first (and only) refuse truck manufacturer to appear on the "small screen" !

1/7/06