If you are evaluating the pros and cons of a truck-mounted service rig versus a traditional carrier-mounted rig, you should consider the characteristics of each option carefully. Truck-mounted rigs offer many advantages over the more traditional carrier-mounted style, however, there are some disadvantages to consider. Often in business you see manufacturers producing similar products, standardized sizes, lengths and shapes. The reason for this is to become more universal; striving to build a product that satisfies as many needs as possible for as many people as possible. In recent years, Sparta has produced an increasing quantity of truck-mounted service rig designs. Unlike traditional designs, these designs incorporate a service rig designed to be bolted to trucks from manufactures such as Kenworth or Peterbilt. Sparta’s service rig designs are different. Universally adaptable much in the same way that a dump box can be mounted in the bed of any truck, Sparta’s designs take advantage of the benefits of this truck-mounted rig style.
Truck-Mounted vs Traditional Carrier-Mounted Rigs
In the past Sparta’s service rigs were mounted on a carrier. A carrier is a custom in-house built frame that all components of the rig sit upon. This includes motor, drivetrain, road light requirements, as well as the driver’s controls and cab. In a truck-mounted design, all these components arrive purchased and assembled in the form of a cab chassis. A cab chassis is a complete truck minus the bed. In short, a traditional carrier is a custom built version of a purchased cab chassis. Although many rigs are still being built on traditional carrier frames, there are several advantages to sourcing a truck-mounted design.
Main Advantages of a Truck-Mounted Service Rig
1. Time/Cost savings
One of the biggest advantages of a truck-mounted service rig is cost. Traditional carriers have to be built from the ground up. Time and cost for engineering, drafting, part sourcing, fabrication and paint of a carrier can slow a rig build substantially. Purchased trucks arrive quickly and at reasonable price with much more luxury items available (wood trim, heated seats, A/C etc.). Highly accurate Canadian models of these trucks give Sparta the ability to design a product that fits the truck. Production can begin long before the arrival of the truck and finishes shortly after.
2. Weight Savings
Much in the way that other automobile companies compete to be the lightest, strongest and fastest; heavy truck manufacturers are no different and spend millions in research and innovation to be the lightest, strongest and most dependable. With that in mind these manufacturers can cut weights that just aren’t feasible at the scale of your average rig build. This is not only done through extensive analysis but “exotic” materials not traditionally found in a rig building shop such as fiberglass and urethanes.
As with any custom build, serviceability becomes a concern with a traditional carrier. Custom made parts can only be purchased from the original parts manufacturer. Otherwise, new custom parts have to be fabricated. This is not only timely but also very costly. The advantage of having a purchased truck allows for parts to be easily purchased at the manufacturer’s dealerships as well as their distributor networks.
Engines and drivetrains wear out on all mechanical systems. Eventually even the biggest, most powerful trucks need replacing. One advantage that truck-mounted rigs have over traditional carriers is that they are modular. This means that the mast and all its components can easily be moved from one truck to another with only the minor cost incurred for engineering to confirm weight distributions and stability for the changeover. This is made possible in part due to purchased trucks having consistently similar dimensions and weight distributions but also because truck-mounted designs are kept much more universal than that of a traditional carrier. Even old service rigs can be outfitted with the most powerful and efficient trucks relatively easily.
5. Creature Comforts
The largest driving factor in my mind of why to choose a truck-mounted service rig over a manufactured carrier is that the truck-mounted version comes packed with creature comforts. Things like air conditioning, larger cabs and nice seats are just some of the items that you will find in a truck cab. This can also be used to attract potential rig operators/employees and give you the competitive edge over the competition.
Main Disadvantages of a Truck-Mounted Service Rig:
It wouldn’t be fair to discuss all the positive aspects of a truck-mounted unit without at least discussing some of the disadvantages. From an engineering standpoint, there are two challenges: purchased trucks have a maximum wheel base, whereas on a carrier the wheel base can be set to almost any reasonable length. The other challenge is that the mast rest for truck-mounted units is positioned behind the cab or roughly 6 feet closer to the base than the carrier mounts. These two dimensional limitations make it more of a challenge to make period one weights. This also increases overhang on the front of the rig. These challenges can be overcome if you are careful and do a proper weight and balance analysis but the customer and engineer both need realistic expectations.
Sparta Service Rigs