DESIGN AND FABRICATION OF AN ENGINE POWERED ROTO-WEEDER

Abstract

The need for an effective weeding equipment suited for the tropics to reduce time loss, labour and operational cost cannot be overemphasized. To this end, an engine-powered, manually operated roto-weeder employing the principle of a rotary tiller and adapted to operate on a deltaic terrain was designed, fabricated and tested in an experimental field. The weeder is powered by a 1.45hp petrol engine with an operating speed of 1130 rpm and equipped with 16 L-shaped standard cutting blades. The depth and width of cut of the blades are 3 and 350mm respectively. At the time of the machine test, the field location had well-drained soil classified as sandy loam with compositions of 76% sand, 7.28% silt and 15.95% clay. The moisture content was 18%wb. Field tests conducted showed weeding field capacity 0.037ha/hr and weeding efficiency 90%. The performance evaluation of the roto-weeder at the tested average operating speed of 0.036m/s were: standard deviation, (SD) 118.84 and coefficient variation (CV) 1.73. These results show the weeder to be effective and efficient. The weeder is simple and locally fabricated. The cost of producing the roto-weeder was estimated at about 275 US Dollars (N35,000.00).