*Compared to previous equivalent models
W.K. Dahms Mfg. Ltd. has been manufacturing the Stone Slinger™ truck conveyor system for more than 43 years and continues to set the standard for efficient delivery and placement of aggregate materials. The original Stone Slinger design was an innovation of W. Keith Dahms, who fitted a truck body with an outboard rear conveyor to replace the wheel-barrow method of distributing material on construction sites.
Today, the company is still family owned and operated. They produce an array of Stone Slinger equipment for precise, high-speed placement of gravel, stone, sand, soil, compost and mulch. Its latest innovative offering is the Stone Slinger OS7 machine. Unlike traditional Stone Slinger units, which are truck-mounted, the OS7 is a self-propelled all-terrain system designed to stay on a jobsite and place hundreds of tons of material until a project is done. The machine is loaded from onsite stockpiles so that it can place material continuously throughout each workday. The OS7 also has increased hydraulic capabilities compared to truck-mounted Stone Slinger units – it will throw stone up to 130 feet in distance, and an average offload of four tons per minute.
A Cat® C4.4 industrial engine powers the machine’s hydrostatic drive, and operators use a handheld control system to drive and steer the OS7, operate the conveyor and unload material.
One of W.K. Dahms’ main objectives was to make the OS7 machine sit as low as possible, allowing it to be easily filled with a skid-steer or wheel loader. That required a design with the engine placed beside the machine instead of underneath the loading belt. However, the company knew this design would leave minimal room for the drive and unloading system, and so it sought an engine with a narrow width.
“We also knew we had to make the leap to Tier 4, but the idea of doing that was intimidating,” Todd Nelson says. Therefore, he turned to Cat dealer Toromont Cat for assistance. Toromont experts worked closely with Nelson, supplying helpful documentation, answering questions and guiding him through the process of specifying the C4.4 and integrating it into the Stone Slinger OS7.
Right engine. Right design. Featuring an engine-mounted aftertreatment, the C4.4 is the ultimate solution for tight-fitting engine quarters. In fact, Nelson says the C4.4 was pivotal for completion of the OS7 model’s wider, lower-sitting profile. “The compact width of the C4.4 engine is what really helped us out with the design of our new machine,” he remarks, noting the machine’s loading height is just slightly over six feet to accommodate smaller-size loaders. Furthermore, with an overall height of only nine feet, the OS7 can fit through a standard overhead door to place material inside a building – a big benefit for many customers.
The benefits keep piling up. This updated engine helps end-users save big by reducing lifecycle costs, thanks to 3% DEF consumption and up to 20% lower fuel consumption compared to previous versions. “Plus, it’s a nice selling point to say we have a Cat engine in the OS7 machine, because the Cat brand is synonymous with high quality and performance,” Nelson states.
See what other Cat industrial engine customers have to say about our engines and related products, and the support they receive from the Cat dealer network.