Effects of knife-incising and longitudinal kerfing pretreatments on high-temperature drying of red pine and pitch pine timbers

Abstract

Effects of knife-incising and longitudinal kerfing pretreatments were analyzed relative to the high-temperature drying of red pine and pitch pine timbers with cross-sections less than 15 cm. Specimens were prepared as round and square timbers with thicknesses of 9, 12, and 15 cm. They were divided into four groups: control, longitudinal kerf, knife-incised, and a combination of knife-incised and longitudinal kerf. Some results from this study, such as commercial availability and application methods of drying schedules, have immense commercial importance. The incising and kerfing treatment can be used not only to improve drying quality but also as a tool for deriving an optimal drying schedule. The kerfing treatment noticeably reduced the surface checks in square timber. However, the incising treatment caused a phenomenon in which the incisions connect to each other and develop into surface checks. The wood characteristics, such as species, type, thickness, and initial MC, had more influence on determining the drying defects than the pretreatments. For the commercial use of the drying schedule used in this study, it can be useful to determine the appropriate drying time in the third step according to the species, thickness, and shape.

Assessing Treatments to Mitigate End-Face Cracking in Air-Dried <em>Acacia dealbata </em>Logs

“…When examining the performance over time, before reaching the FSP, the K-3k variant shows greater water loss than the reference, achieving MC values near 30% approximately 15 days earlier than the other samples. In line with Lee et al [44], this suggests that incisions or cuts affect the moisture distribution within the log, influencing the formation of the moisture gradient. The three kerfs reduce the distance between the core and the outer wood, diminishing the moisture differential, facilitating water transport, and increasing the moisture exchange area along the entire piece.…”

Effects of Pretreatment for Controlling Internal Water Transport Direction on Moisture Content Profile and Drying Defects in Large-Cross-Section Red Pine Round Timber during Kiln Drying

“…When the tensile stress on the surface exceeds the binding strength across the surface cells, checks are known to form on the surface to reduce the quality of dried timber (Kim et al, 2017;Lee, 2020). The kerfing process is used to prevent surface checks, whereby the drying stress in the tangential direction during drying is reduced so that checks are prevented from surfaces other than the kerf surface (Jung et al, 2022;Lee and Eom, 2021).…”