Digger Derrick & Pressure Digger Augers: Dirt vs Rock Guide | Monster Equipment
Setting poles is only as fast as the hole. Whether your crew runs a digger derrick for distribution work or a pressure digger for deeper, harder ground, the auger on the end of the Kelly bar decides how much of the day goes to digging and how much goes to fighting the ground. This guide walks through the auger types Monster Equipment carries, what to check before you order, and how to match tooling to the rig you already own.
Monster Equipment is a family-owned dealer at 1223 Porter Rd in Sarasota, Florida, founded in 2010. We sell reconditioned utility trucks and new tooling to utility, telecom, construction and sign crews, and we ship nationwide.
Why the Auger Matters as Much as the Truck
A digger derrick or pressure digger is a big investment. The auger is a small part of the cost, but it is where the work happens. The wrong auger for the soil can mean:
- slow penetration and more time per hole
- extra wear on teeth, pilot bits and flighting
- more strain on the drive and Kelly bar
- holes that wander or come out oversized
Choosing the right diameter, tooth style and drive connection up front avoids most of those problems.
Auger Types We Carry
Our augers category lists the tooling we have now. It falls into three groups.
Dirt augers for digger derricks
Dirt augers use replaceable dirt teeth and are meant for soil, sand and clay. One example on our lot is a new 36 in digger derrick dirt auger (stock 52422) with a 2-1/2 in hex drive, a 3-3/4 in DOM stem and 1650/1652 dirt teeth. The hex size has to match your digger's drive, so confirm it before you order.
Rock augers for pressure diggers
Pressure diggers can push down on the tool, so they are often paired with rock augers for limestone, caliche, frozen ground and mixed rock. We list new Max Cut Econo rock augers in 30 in (stock 091824) and 36 in (stock 082124). Each listing shows 1 in flight at 24 in pitch, .990 carbide teeth and a 3 in Kelly drive box.
Built-to-order dirt, carbide and rock augers
When you need a size we don't have in stock, we can build to order. Our built-to-order line covers dirt, carbide and rock augers in 8 to 48 in diameters for digger derricks and pressure diggers. Call us with your rig, drive and soil, and we'll quote the build.
How to Match an Auger to Your Rig
Before you order, gather four pieces of information.
1. Drive connection
Digger derricks commonly use a hex drive. Pressure diggers commonly use a Kelly bar drive box. The size has to match exactly. Check your current auger, your Kelly bar or the manufacturer's manual. If you aren't sure, send us a photo of the drive end and a tape measure across the flats.
2. Hole diameter
Diameter is set by the pole class and your utility's or customer's specifications, not by the auger. Order the diameter your job specifies. If your crews set a mix of pole sizes, many fleets keep more than one auger per truck.
3. Soil and rock
- Mostly soil, sand or clay: a dirt auger with dirt teeth is usually the starting point.
- Hard pan, caliche, frozen ground or broken rock: look at carbide or rock tooling.
- Solid rock: a rock auger on a pressure digger is the usual approach, and some jobs need other methods entirely.
Your crew knows the ground in your territory better than anyone. Tell us what they hit most often and we can help narrow the choice.
4. Your digger's limits
Larger and heavier augers put more load on the digger. Stay within the auger size and weight limits in your digger derrick or pressure digger manufacturer's documentation. If you aren't sure what your unit can turn, check with the manufacturer before ordering a bigger tool.
Care and Wear: Getting More Holes From an Auger
A few habits extend auger life:
- Inspect teeth and the pilot bit daily. Replace worn teeth before they wear into the tooth holders.
- Check flighting for cracks and bends, especially after hitting buried rock or debris.
- Keep drive connections clean and check for wear or slop in the hex or drive box.
- Store augers off the ground and secured on the truck or in the yard.
Tooth part numbers matter. When you order replacement teeth, match the tooth style shown on your auger (for example, the 1650/1652 dirt teeth on stock 52422).
Augers, Trucks and Trailers in One Call
Augers are only part of a pole-setting crew's setup. Many of our customers also look at:
- Bucket trucks for line work after the pole is set
- Pole trailers for hauling poles to the site
- Buckets and baskets and other parts and accessories
Our shop on Porter Road also inspects hydraulics at no cost, so if your digger's drive or circuits are acting up, we can look at it before you blame the tooling.
Frequently Asked Questions
What sizes of augers does Monster Equipment carry?
We list in-stock 30 in and 36 in augers and build dirt, carbide and rock augers to order in 8 to 48 in diameters. See the augers category for what is available today.
What is the difference between a dirt auger and a rock auger?
A dirt auger uses dirt teeth for soil, sand and clay. A rock auger uses carbide teeth and heavier construction for rock and hard ground and is commonly paired with a pressure digger.
How do I know which drive my digger uses?
Check the end of your current auger or Kelly bar, or your manufacturer's manual. Our in-stock 36 in dirt auger uses a 2-1/2 in hex. Our in-stock rock augers use a 3 in Kelly drive box. Send us a photo if you aren't sure.
Are your augers new or used?
The augers in our augers category are listed as new. Our trucks and trailers are reconditioned used units.
Do you ship augers outside Florida?
Yes. Monster Equipment sells nationwide. Call for shipping options to your yard.