New Stone Slinger OS7 Works for Maximum Production

Wed November 06, 2019 - West Edition #23
W.K. Dahms Mfg. Ltd.


The OS7 is fitted with a 7-yd. hopper with wings leading to a 19-ft. long high-speed throw conveyor. It can be loaded with an excavator, wheel loader or even a skid steer loader.
The OS7 is fitted with a 7-yd. hopper with wings leading to a 19-ft. long high-speed throw conveyor. It can be loaded with an excavator, wheel loader or even a skid steer loader.
The OS7 is fitted with a 7-yd. hopper with wings leading to a 19-ft. long high-speed throw conveyor. It can be loaded with an excavator, wheel loader or even a skid steer loader. The hydrostatic drive powered by a Cat C4 Tier IV Final engine. Operators can reposition the OS7 on the site using a remote-controlled belt pack. With efficient loading, the OS7 can accurately spread 1,800 tons in a single eight-hour shift.

Ground Solutions/Bedrock Slingers bills itself as "the Material Placement Guys" serving Colorado and a growing region around the state. What began as a single conveyor truck that Jordan Kamps purchased in 2003 has now grown into a fleet of 17 mobile material placement systems filling a unique niche in a wide range of construction applications.

The truck fleet quickly became a popular solution with builders and concrete contractors placing gravel fill into foundations or spreading soil or woodchips on landscape projects. The high-speed conveyors off-load the truck by launching the material to the target area in a controlled stream up to 110 ft. away. The systems' precise placement dramatically reduces time and costs for wheelbarrow labor with less waste and clean-up.

The latest addition to Bedrock's fleet, a Stone Slinger OS7 machine, takes the concept and its cost-savings even further.

Self-Contained Slinging

The OS7 at Ground Solutions/Bedrock Slingers is the first production unit of its kind from the originator of "slinging" technology. Scott Nelson, president of W.K. Dahms Mfg. Ltd, explains the difference in the OS7. "The traditional Stone Slinger mounts our hopper and high-speed conveyor system to our customers' choice of truck chassis. The OS7's built with the same "slinging" technology but without the truck. It's a self-propelled all-terrain system we designed to stay on the job site until the project is done. Instead of running sorties to and from the gravel pit or soil supplier, it's loaded from onsite stockpiles so it can place material continuously all day long."

Nelson estimates that, with efficient loading, the OS7 can accurately spread or place up to 1,800 tons of material in a single eight-hour shift. The performance and cost-efficiency of the OS7 has opened new doors for Ground Solutions/Bedrock Slingers, now taking on major projects from Wyoming to Texas.

Onsite Solution for Big Jobs

With several large projects under way, Ground Solutions/Bedrock Singers is the right place for the OS7 to prove itself. For General Manager Justin Griess, the OS7 began with a question of how to optimize a return on their fleet investment. "The Slinger is a specialized piece of equipment," he said, "So, naturally, you have more dollars attached to it than a basic dump truck. You want to keep it working on the site as much as possible."

Griess and Kamps brought their notion for a unit that stays on site to Nelson, looking for a way to keep the Slinger slinging. With the material placing system stationed at the job site, they could then use the lowest cost method possible to deliver material to the site, then use available loading equipment to fill the hopper as it continues slinging material into place.

"The idea was already out in the market, but we had some specific needs in mind. So, we went back to our source. The people at Dahms were willing to work with us, to build an all-terrain onsite Slinger system with the features and capabilities we were looking for."

The team in Colorado has a long history with W.K. Dahms, St. Jacobs, Ontario. "Most of the 14 units we have in service were built by Dahms," Griess reported. "We tried other conveyor trucks in the past but those remaining units will be replaced with genuine Stone Slingers."

The Right Slinger for Every Job

The traditional Stone Slinger trucks will continue to play a large role in the business of Ground Solutions/Bedrock Slingers. Truck platforms are still recommended for smaller projects, under 150 tons, or those that may require only a partial load, and for job sites that don't have space available to stockpile material. Most urban residential jobs fall into that category, so Kamps sees the OS7 focused on industrial and commercial developments.

The OS7 is fitted with a 7-yd. hopper and 26-in. wide live bottom belt, leading into 19-ft. long high-speed throw conveyor. With its hydraulically operated wing extensions, the hopper receives material cleanly from larger excavators and loaders, with little spillage. W.K. Dahms worked on its conveyor lift geometry, to give the OS7 an additional 3 degrees of incline on the throw conveyor. The OS7 Slinger finishes with an approximate discharge height of 150 in. from ground and can throw material to a distance of up to 130 ft., a distance that is even farther than Stone Slinger trucks.

Remote-Controlled Mobility

The hydrostatic drive that lets operators reposition the OS7 on the job site is powered by a Cat C4 Tier IV Final engine with direct coupled hydraulic pumps. The system is operated and steered from a remote-control belt pack, similar to the kit that W.K. Dahms developed for its trucks with Creep Drive system. The platform has four steering modes: front-wheel, rear-wheel, articulated and crab, which offers an additional advantage over truck-mounted conveyors. According to Griess, "It's very agile. We've taken it into places you would never attempt with a truck. It's impressive the job sites we have gotten it into. It performs well on uneven ground, and it has a manually operated hydraulic leveling system to give it a stable footing when it's working on a side slope."

The machine also sits two feet lower than previous onsite placement-type systems, allowing access into buildings through bay doors Bedrock could never access before. The rear loading height is just over 6 ft., so smaller equipment such as skid steers also can be used to feed the OS7. Griess noted that this system gives Bedrock customers more options for using their own crews and equipment to manage costs. "We can work with whatever loading equipment is available on the site. We can bring in our own loaders, of course. But customers will often decide that, rather than let a wheel loader and operator stand idle while we're placing material, they will look after loading the hopper."

"The same idea applies to stockpiling. We have dump trucks to bring in whatever material the job calls for. But if the customer has a ready fleet, they can put it to work getting material onto the site, on their own time."

About Stone Slinger

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 concept was an innovation of W. Keith Dahms, who first fitted a truck body with an outboard rear conveyor to replace the traditional laborious and costly wheel barrow method of distributing material on construction sites. Stone Slinger today represents a diverse family of systems for precise, labor-free placement of gravel and stone, sand, soil and mulch materials.

For more information, visit www.stoneslinger.com.