• 
 
 ET-145 May 1939 
 
 United States Department of Agriculture 
 Bureau of Entomology and Plant Quarantine 
 
 A POWER-DRIVEN MIXER FOR MAKING EMULSIONS 
 AND OTHER SPRAYS IN THE FIELD 
 
 By Fred P. Dean, 
 Division of Fruit Insect Investigations* 
 
 In experimental field spraying it is often desirable to have 
 a power-driven mixer for making emulsions and for mixing other spray 
 materials that are difficult to handle with ordinary hand methods. 
 Spray mixtures can be made at the laboratory where electricity is 
 available, but it is often desirable to do the mixing in the field. 
 This is particularly true when working with unstable emulsions that 
 must be used immediately after mixing, with bulky mixtures that are 
 not easily transported, or with materials that are incompatible if 
 mixed together in concentrated form for more than a few minutes. 
 
 The apparatus described here has proved satisfactory for the 
 purpose at the Yakima, Wash., laboratory. It consists of a used 
 gasoline washing-machine motor mounted in a steel frame, a flexible 
 power shaft, an agitator, and a mixing container. It is shown in 
 figures 1 and 2. The motor mounting differs from that of some of 
 the models which are available in that it is suspended from the 
 frame rather than resting on a base. However, the frame can easily 
 be changed to fit any motor. It also has a built-in chain and 
 sprocket arrangement geared to turn the power take-off at approxi- 
 mately 1,750 r. p. m. Some motors do not have this feature. 
 The frame on which the motor is mounted is made of welded 1-inch 
 angle iron and is 19 inches long, 15 inches wide, and 42 inches 
 high. The height should be such that the flexible shaft will not 
 be bent at too sharp an angle. 
 
 The flexible power shaft is 42 inches long, although several 
 units can be used if a greater length is needed. This type of 
 shaft is available in a number of weights for use at various speeds, 
 is made by a number of manufacturers, and is usually carried in 
 
 ♦The writer is indebted to C. W. Murray, Division of In- 
 secticide Investigations, for suggesting the construction of a 
 power-drjven mixer that could be operated in the field. 
 
- 2 - 
 
 stock by hardware stores. The necessary end fittings may be pur- 
 chased with the shaft. They include the motor connection which 
 fits over the end of a 1/4-inch shaft and a chuck that holds the 
 end of the agitator shaft. 
 
 The agitator can be purchased, or a satisfactory one can be 
 made from sheet metal by cutting it in the shape of a propeller. 
 For ordinary use an agitator 3 inches long with 1-inch blades, 
 set to force the spray mixture toward the bottom of the container, 
 is satisfactory. This is attached to the end of a 1/4-inch steel 
 rod long enough to reach from the chuck to approximately 1 inch 
 from the bottom of the container. 
 
 This container consists of an ordinary 50-pound bucket, such 
 as is commonly used for paints and insecticides, to which have been 
 welded a bracket and clamp to hold the end of the power shaft. 
 Since this bucket is not readily detachable from the agitator, it 
 is necessary to pour the contents into a second bucket before trans- 
 ferring it to the spray tank. One suggested improvement is the 
 designing of a detachable container to eliminate this inconvenience. 
 
 In operation the motor and stand are securely fastened back 
 of the cab of a 1/2-ton truck, and the mixing bucket rests near the 
 tail gate where it is readily accessible. However, the entire 
 apparatus can be removed from the truck if desired. 
 
Figure 1. — Power-driven spray mixer. 
 
 "*** 
 
 — nn 
 
 Figure 2 — Close-up of motor and frame assembly. 
 
UNIVERSITY OF FLORIDA 
 
 3 1262 08537 0848