How to choose a soil sampling drill

Little Beaver’s Mike Hale examines some of the options available from the company for contractors who are looking to enter the soil sampling market or who require rig that is lightweight and easy to transport.
How to choose a soil sampling drill How to choose a soil sampling drill How to choose a soil sampling drill How to choose a soil sampling drill How to choose a soil sampling drill

The LST1G+. It is a lightweight trailer-mounted drill rig that can be towed using an ATV or small pickup

Mike Hale

Little Beaver realises that not all contractors need or want to run a fleet of large truck-mounted geotechnical drilling rigs. In response to the requests of such users, it offers a line of soil sampling rigs that can be trailer mounted or carried on the back of a small pick-up. These rigs are ideal for those who want the convenience of owning soil sampling equipment, such as site prep or design-build contractors, portable soil sampling tools are an economical foot in the door.

Common characteristics across the four Little Beaver soil sampling rigs from Lone Star are portability; the ability to drill to depths of 100ft; the ability to work in various types of soil, including sand, clay and soft rock formations; and comprehensive soil sampling capabilities, allowing users to conduct standard penetration tests, geotechnical testing, split spoon sampling and hollow stem sampling.

The decision as to which rig is the best option can be made taking into consideration the planned use and the types of worksite it will be used on.

For those users with a small towing vehicle and a smaller budget the recommended drill is the LST1G+. It is a lightweight trailer-mounted model that can be towed using an ATV or small pickup.

It is equipped with a 4in-diameter auger for drilling 6in boreholes to depths of 100ft, and it includes a tower, cathead and 140lb safety hammer for standard penetration testing. It offers a lifting capacity of 5,000lb to ensure easy removal of augers and extensions. Power comes from a Honda 20hp petrol engine and the hydraulic system provides a speed of 150rpm at 10gpm. For added versatility, Little Beaver's optional interchangeable head allows users to switch from soil sampling to water well drilling.

If the majority of the drilling will be doing is through hard soils and against short deadlines the LST1G+HD is the rig of choice. It maintains highs speeds even when powering through harder soil and has good levels of torque and pull/push back force as well as a healthy rpm.

A key feature of the LST1G+HD is a planetary reduction gearbox for as much as 1,100ft-lb of torque and has a reduction mechanism for 8,500lb of push-/pull-back force for tackling challenging soil conditions. The unit drills as deep as 100ft with an optional 4.25in hollow stem auger for standard penetration tests and soil sampling. In order to make the most of this power, Lone Star has increased the strength of the steel frames on the unit by 50 per cent when compared to the LST1G+.

The unit comes standard with a 27hp Kohler petrol engine that features electronic fuel injection and a powerful 3,000psi hydraulic system. The hydraulic power pack operates at 13.5gpm to achieve a rotary speed as fast as 200rpm that will be enough to make short work of larger jobs when time constraints are an issue.

With more and more states and cities in the USA requiring automatic hammers for standard penetration testing (STP), Little Beaver recognises that users need a drill that gives consistent SPT results. Regulations aside, if regular SPT work is planned it makes sense to purchase a drill with an automatic hammer to reduce worker fatigue, creating a safer and more productive job site. However, because an automatic hammer configuration, such as the LST1G+HDA adds weight to the rig, the capacity of the towing vehicle has to be considered too. Fortunately, the LST1G+HDA has the option of trailer or truck mounting.

The LST1G+HDA is the newest of the company's geotechnical rigs and was created to addresses the growing need for automatic hammers for soil sampling applications. The automatic hammer's design ensures precise, foolproof sampling depths as well as easy operation. The drill includes a hydraulic winch with 1,500lb of pull and features a planetary reduction gearbox with up to 1,100ftlb of torque. As standard, it has a 3,000psi hydraulic system and 27hp Kohler EFI petrol engine. A rotary speed of 100rpm is achieved with a 12.5gpm hydraulic power pack.

The final option from Little Beaver, which is suitable for operators who regularly work in locations with limited access is the Big Beaver auger drill rig. This is a rig with transport dimensions of 26in wide and 80in tall, meaning it is compact enough to fit into an elevator to reach a basement or easily fit through gates and doorways.


 he compact ig eaver auger drill rig is compact enough to work in locations where access is extremely limited The compact Big Beaver auger drill rig is compact enough to work in locations where access is extremely limited


Designed to work with 4 - 18in D-series augers and when deep holes are required, auger extensions can be added to drill down to 30ft with a 16in auger and up to 100ft with a 6in auger, depending on soil conditions, the Big Beaver is the most powerful earth drill produced by Little Beaver. It is hydraulically driven by the company's Hydraulic Power Source.

The Hydraulic Power Source is a compact power unit featuring an oil cooler with 10in fan and a four-gallon fuel tank. Not only does it efficiently power the Big Beaver, but it also serves as an attaching point for the torque tube. For added versatility, the Power Source can also be used to power other hydraulic tools, including concrete saws, breakers, tampers and chainsaws. Engine options include 20, 24 or 27hp Honda units.

Mike Hale is sales manager for Little Beaver, America's number one source for hole digging equipment