\OARD September 1942 ET-200 United States Department of Agriculture Agricultural Research Acministration Bureau of Entomology and Plant Quarantine HAKD-OPERATED EQUIPMENT FOR PRECISICN BUSTING By C. H. Batchelder and A. V. Ccsenza, Division of Cereal and For- age Insect Investigations Dust guns with small discharge tubes are useful for applying insecticides to restricted parts of a plant with precision, econ- omy, and freedom of the operator from the annoyance of a dust cloud. The equipment shown in operation in figure 1 consists of two parts, (1) a dust gun, which holds a supply of insecticide and provides a means of directing the dust discharge, and (2) a port- able air pump. The parts may be assembled from readily available or salvaged materials at comparatively lew cost. The Dust Gun The dust gun (figure 2) was constructed from these parts: A mason-type quart jar, one 12- inch length of 5/16-inch ccpper or steel tubing bent into a "U," one 10 -inch length of 1/4-inch tub- ing, one 5/16-inch, straight, union, compression coupling with one sleeve and two nuts, one quarter-inch right-angle ccmpressicn coup- ling with one sleeve and two nuts, a piece of strap iron 3/4 by 10 inches, and a 4-inch length of garden hose. Metal tubing and ccm- compression couplings are used in fuel lines of oil stoves and automobiles. The strap iron is bored to receive the couplings, bent to form a grip support, and fastened over a gasket to the jar top. • A Portable Air Pump Details of a portable air pump are shown in figure 3. First mount an automobile tire pump on a wooden staff (3/4 by 3/4 by 42 inches) by means of thin sheet-iron straps and an eyebolt. Fasteu the end of the tire-pump plunger rod in a foot brace made of strap iron or of stcut wood. If the rod is not threaded and a 1- by 3/4- by 8-inch piece of hardwood is used for the foot brace, bore a hole through the wood, pass the rod through it, peen over the end of the rod sufficiently to held a washer in place, and tack a piece of - 2 metal over the end of the rod. Three eyescrews hold a 1/8- to 3/8-inch guide rod, 31 inches long, bent at right angles just beneath the staff handle and fastened to the foot brace by the same means used for the plunger rod. Connect the tire pump and dust gun with a 30-inch length of rubber tubing (1/4 inch inside diameter) , and the outfit is ready for use. Ordinary tire-pump tubing is not large enough in diameter to operate the dust gun. Operating the Equipment Air compression is developed by pushing the pump tcvrard the ground, and the plunger rod is held by the foot brace during the back stroke. Both guide rod and staff handles are grasped in carry- ing the equipment. It is necessary to shake the dust gun occasion- ally in order to keep the dust in a "fluffed" condition. Figurer 1. — Eqiiipment in operation. The operator stands with one foot on the foot brace yrhlle pumping air through the dust gun. Figure 2. — Dust gun, showing tube cOTipression couplings, gaskets, U-shaped air-intake tube, dust si^)ply, discharge tube, and parts foraing the grip. Digitized by the Internet Archive in 2013 http://archive.org/details/handoperatedequiOOunit Figure 3. — Details of the air pvaspi (a) Adjustable staff handle, (b) medium-siaed tire punp, (c) sheet-metal clamp, (d) pump plunger rod, (e) plunger-rod eyebolt, (f) foot brace, (g) guide rod, (h) air hose, and (i) dust gun. A simpler foot brace maj be made of wood, as described on page 1. UNITED STATES DEPARTMENT OF AGRICULTURE OFFICE OF THE SECRETARY WASHINGTON, D. C. OFFICIAL BUSINESS PENALTY FOR PRIVATE USE TO AVOID PAYMENT OF POSTAGE, $300 STATE PLANT HOARD OF FLORIDA LIBRARY ET GAINE3VILL FLA