Introduction: Earth Auger

Picture of Earth Auger

Here in California after several years of drought, we have ripped out the lawn and installed a drought tolerant landscape. Because of this, our trees have suffered. So I needed to install root feeders. The easiest way to do this is to bore a hole into the earth and fill it with pea gravel to provide a path for water to get to the roots. A couple of standard drip lines should provide more than enough water to nourish the tree.

Here I'll show you how to make an auger that is perfectly suited to this task.

Step 1: Tools and Materials

Tools

  • Cutting torch
  • Arc welder
  • Angle grinder
  • Vise


Materials

  • ¼" plate steel

  • ¾" emt conduit

  • 1½" pipe

Step 2: Metal Prep

Picture of Metal Prep

Cut a piece of quarter inch plate steel as wide as the width of your intended hole. It should be at least 12" long. Weld a piece of 1½" pipe onto one of the short edges of it. This pipe will be your twisting handle. Use caution when welding to galvanized pipe. The zinc clad of the galvanize it quite poisonous when it burns so use adequate ventilation.

Step 3: Twist!

Picture of Twist!

Clamp the remaining short end into a vice. Just enough to get a secure grip. From here heat the entire plate of steel. When it's nice and hot, grab the pipe and twist anti-clockwise. Doing this will make for an auger that digs when rotated in clockwise direction.
Many factors come into play here. How hot you can get the plate steel. How secure your vise is. How strong you are. I wasn't able to get my plate very hot and my vise is not very secure because it's free standing on an old table base.
The result is I was only able to get about one full twist into the metal. It also went off at a weird angle, so I was only able to salvage a small bit of the twist. Luckily, it was more than enough to do the job.

Step 4: Cut Out the Auger!

Picture of Cut Out the Auger!

Cut the auger away from the pipe twisting handle and put a crude point on it. Hit it with the angle grinder to give it a nice clean edge. And remember, that steel blade guard is there for a reason. Leave it on the grinder.

If you didn't get enough twist on the tip of the auger blade (like I didn't), just heat it up some and bend it with a big wrench till you like the angle. Quench the blade in water while it's still hot to harden the steel.

Step 5: Attach the Auger to a Handle

Picture of Attach the Auger to a Handle

Slot a piece of ¾" EMT conduit and wedge the auger blade into it. Weld it in place. Clean up the twisting handle from where you separated it from the blade and weld it on to the other end of the ¾" EMT.

Step 6: The Auger Is Now Complete! Start Digging!

Picture of The Auger Is Now Complete! Start Digging!

The auger is pretty easy to use. Just stick it in the ground and twist. It took about 15 minutes to dig a 2' deep hole.

We really love our trees, so these root feeders were essential.

Comments

JoeB95 (author)2015-11-25

Vehicle driveshafts are hollow and quite thin. Torque as it turns out, is mainly carried by the skin or outer layer of a shaft so solid or heavy often provides no advantage.

Psalms116 (author)2015-11-23

Smart idea. I would suggest though to use 3/4" schedule 40 black iron pipe instead of EMT. The EMT is very thin wall and if you get into any very hard soil or roots the EMT may not hold up. The black iron pipe also is not galvanized so it eliminates that hazard as well.

Marsh (author)Psalms1162015-11-23

It would be stronger, but this held up well and we have pretty hard soil here.

About This Instructable

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Bio: I'm an environmentally conscious experimenter who loves to bring people together, build things, and when possible...blow things up! See us on YouTube too ...
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