Comparing sawing efficiency of framed and freehand chainsaw milling in Uganda
Abstract
Chainsaw milling of logs is an important economic activity in Uganda since it produces about 80% of the domestic timber supply especially in rural area. However, chain-sawn timber production has been banned in Uganda partly due to the large waste or residues associated with this operation. There is need for an alternative in-situ processing method that improves timber recovery. A study was conducted on the use of the chainsaw fitted with frames to determine its effects on timber recovery for two common timber species in Uganda: pines and eucalyptus. The objectives were to determine the milling recovery rates of these species and the time input for milling logs using both framed and freehand chainsaw operation. The study also examined how common log characteristics (diameter and tapering) affect timber recovery when using the framed and freehand chainsaw machine. The research was conducted in Kikandwa Sub County, Mubende district in the Central Region of Uganda. A total of 80 logs from the two species with volume 92.9m3were processed into timber using the two chainsaw milling types. The average recovery was 31.64m3of sawn timber at an average recovery of 28.0%and 32.5% for pine and eucalyptus respectively using freehand chainsaw. While 36.1% and 37.5% using framed chainsaw, a rate substantially lower than the reported recovery (40%) in chain-saw with free hand.