How to Build a Field Classifier
by Chuck Cummins, Mechanical Design Engineer

Materials and Equipment

      It takes about six hours to build one of these field classifiers after you have accumulated all the materials necessary to build it.

      Insert pop rivets with the heads out and the body and washer on the inside. This will keep the pop rivet from snagging on the outside and will help break up clogs, clay, and moss when you rotate the classifier.

      Put the classifier into a 5-gallon bucket of water. Put the equivalent of three shovels full of sample material into the classifier. Grab the handle with both hands, lift slightly, rotate back and forth about three times, surge up and down a couple of times, and your sample is classified.

This classifier was designed and tested by mechanical design engineer Chuck Cummins. If you would rather that he build one for you for $35.00 plus shipping and handling, contact Chuck Cummins at Scientific Engineering, 31013 Weld County Rd. 17, Windsor, CO. 80550. Telephone: 970-686-2238. E-mail:


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