The Rigid WD19560 Shop Vacuum meets the Holey-Moley Digger Vacuum Requirements for optimum post hole digging.  This vacuum rated at 6.5 HP pulls 203 CFM with a 2-1/2″ hose.  In addition, the vacuum should have two sturdy wheels on an axle.

A 6 inch diameter post hole will generate approximately 15 pounds of soil per foot of depth.  The volume of the removed soil will be approximately 2 gallons.    A 6-inch diameter hole, 3 feet deep, will generate 6 gallons of soil weighing approximately 45 pounds.  Likewise two holes will generate 12 gallons of soil weighing 90 pounds.

This weight can rapidly become unmanageable.  So a shop vacuum with larger wheels on an axle and a steel tube of around 16 gallons will still have head room around the filter after digging two holes.   The sturdy handle and wheels allow for easy movement of the dirt.

In addition, the two wheels and larger tube make for easier dumping of the dirt out of the shop vacuum.

Rigid WD19560 Shop Vacuum Specifications

It has been our experience that the Rigid Shop Vacuum WD19560 fits the bill for the ideal vacuum.  It has the 2-1/2″ hose, pulls 204 CFM and carries the 6.5 HP rating.  This vacuum has two large wheels and a sturdy detachable handle.  This vacuum is easy to break down and transport in a car.

We have dug holes 20 feet deep with this vacuum and the Holey-Moley Digger.

Rigid WD19560 Shop Vacuum
Rigid WD19650 Shop Vacuum

 

Fence Post Hole Digger
Holey-Moley Post Hole Digger

 

See the Rigid WD19560 Specifications for more information.