Engineers Arnold S. Juliano, Leo B. Molinawe and Ricardo F. Orge reported that a differential power tiller developed at UP Los Banos, which has better performance than other power tillers, was used as their basis in developing the power tiller. The tilling width of the rotavator is 70 cm (centimeters). The power tiller is powered by a 6 hp (horsepower) gasoline engine.
Juliano said the walking-type power tiller showed good performance and acceptability in tests conducted in rainfed farms in Talugtog, Nueva Ecija. Its six-horsepower engine was sufficient to run the power tiller with rotavator attachment.
Farmers who witnessed the tests observed that the rotavator’s pulley and belt transmission is better than a chain and sprocket transmission. They said the latter slips and breaks down whenever it hits hard soil.
In fact, a former barangay captain has already requested PhilRice engineers to convert his power tiller into one with rotavator attachment so that he can use it for dry land preparation instead of using a small four-wheel tractor that requires much higher fuel consumption, high maintenance, and high risk for breaks down.
The power tiller was also used for second and third rotavation to fully pulverize the soil before dry seeding. With some residual moisture still in the soil, the rotavator performed excellently in a depth of 10 to 20 cm. No significant difference was observed on the speed of the machine in the second and third rotavation.
The power tiller rotavated with a forward speed of two kilometers per hour, a working width of 70 cm, and an average field capacity of 1.04 hectares a day.
During the field tests, Talugtog farmers had a first hand experience in operating the power tiller and most of them were satisfied with its performance. They said that its rotavation output is finer than the disc plow. However, they suggested the following improvements, which made the power tiller more acceptable and encouraged many rainfed farmers to adopt it:
1. Increased width of the rotavator to reach the soil near the dike or levee and eliminate side plowing;
2. Spring-loaded idler for the belt and pulley transmission connecting the engine and rotavator top minimize slippage during operation and eliminate damage to engine parts; and
3. Lower handle for operator lifting convenience.
In tests conducted in wet field condition, the performance of the power tiller was comparable with the small four-wheel tractor. Rotavation in wet fields was easier due to the presence of water. The time, fuel and labor allocation for the power tiller were 50 percent lower than for other types. – Sosimo Ma. Pablico