How to properly bench in the Sonic Tracker

When using a Sonic Tracker, it's important to understand the proper procedure for benching in the tracker.

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How to properly bench in the Sonic Tracker

Setting the tracker to zero

When initially setting up the system to use a Sonic Tracker, you will want to set the cutting edge on the ground for the zero reference.

To initially set up the tracker, manually place the blade so it is just resting on the ground.

When setting the cutting edge on the ground for the zero reference, make sure both sides of the blade are resting on smooth ground.

Set the tracker to on grade. This can be done by just pushing the smart switch buttons.

Set the upper switch to zero, and push the Enter button on the control box, which sets the LCD to read 0.00.

Now, whenever the blade is at the same elevation as the grade reference—no cut or fill—the LCD will be set to 0.00.

Error induced by cutting edge wear

Be aware of cutting edge wear, which is common at the edges of the blade.

Setting to 0.00 with the tip of the blade on the ground would cause the blade to undercut farther in from the edge.

When verifying the blade is matching grade, look about 18” in from the end of the blade.

Understanding the tracker operation and features enables you to properly position the tracker for a variety of job applications

The tracker can be set to match a previously cut surface.

Setting the tracker to -1.00' cut

With the Sonic Tracker previously set to 0.00, if the operator wants to cut 1 foot below an existing surface, it's as simple as turning the grade adjustment knob until the display reads -1.00. When dialing from 0.00 to -1.00, the working window moves up exactly one foot and tracks the new reference.

Track an existing road

Once the blade has been referenced to 0.00, then the operator can just dial in any depth of cut they want.

This job had a 1-foot vertical cut to finish subgrade.

Track a stringline

To cut two feet below the stringline, just dial -2.00 into the control box.

The working window moves up exactly two feet from the cutting edge.

To place a half foot lift of base rock on top of the finish subgrade, just dial in -1.50.

The cutting edge will now be set to cut grade 6” (.50’) above subgrade, or 1.50 feet below the stringline.

Working height

When installing the Sonic Tracker on your machine, consider the overall working height adjustment available so that your tracker is properly set, that is, not requiring you to reposition the tracker.


When tracking a stringline, the recommended height from the bottom of the tracker to the stringline is 24".