Seasoning of Wood
A TREATISE ON THE NATURAL AND ARTIFICIAL PROCESSES EMPLOYED IN THE PREPARATION OF LUMBER FOR MANUFACTURE, WITH DETAILED EXPLANATIONS OF ITS USES, CHARACTERISTICS AND PROPERTIES
ILLUSTRATIONS
BY JOSEPH B. WAGNER AUTHOR OF COOPERAGE
NEW YORK D. VAN NOSTRAND COMPANY 25 PARK PLACE 1917
COPYRIGHT, 1917, BY D. VAN NOSTRAND COMPANY THE·PLIMPTON·PRESS NORWOOD·MASS·U·S·A
The seasoning and kiln-drying of wood is such an important process in the manufacture of woods that a need for fuller information regarding it, based upon scientific study of the behavior of various species at different mechanical temperatures, and under different drying processes is keenly felt. Everyone connected with the woodworking industry, or its use in manufactured products, is well aware of the difficulties encountered in properly seasoning or removing the moisture content without injury to the timber, and of its susceptibility to atmospheric conditions after it has been thoroughly seasoned. There is perhaps no material or substance that gives up its moisture with more resistance than wood does. It vigorously defies the efforts of human ingenuity to take away from it, without injury or destruction, that with which nature has so generously supplied it.
In the past but little has been known of this matter further than the fact that wood contained moisture which had to be removed before the wood could be made use of for commercial purposes. Within recent years, however, considerable interest has been awakened among wood-users in the operation of kiln-drying. The losses occasioned in air-drying and improper kiln-drying, and the necessity for getting the material dry as quickly as possible after it has come from the saw, in order to prepare it for manufacturing purposes, are bringing about a realization of the importance of a technical knowledge of the subject.
Since this particular subject has never before been represented by any technical work, and appears to have been neglected, it is hoped that the trade will appreciate the endeavor in bringing this book before them, as well as the difficulties encountered in compiling it, as it is the first of its kind in existence. The author trusts that his efforts will present some information that may be applied with advantage, or serve at least as a matter of consideration or investigation.
J. B. Wagner
SEASONING OF WOOD
TIMBER
Characteristics and Properties
Structure of Wood
Properties of Wood
Classes of Trees
CONIFEROUS TREES
WOOD OF THE CONIFEROUS TREES
BROAD-LEAVED TREES
WOOD OF BROAD-LEAVED TREES
GRAIN, COLOR, ODOR, WEIGHT, AND FIGURE IN WOOD
DIFFERENT GRAINS OF WOOD
ENEMIES OF WOOD
Ambrosia or Timber Beetles
Round-headed Borers
Flat-headed Borers
Timber Worms
Powder Post Borers
Conditions Favorable for Insect Injury—Crude Products—Round Timber with Bark on
How to Prevent Injury
Saplings
Stave, Heading and Shingle Bolts
Unseasoned Products in the Rough
Seasoned Products in the Rough
Dry Cooperage Stock and Wooden Truss Hoops
Staves and Heads of Barrels containing Alcoholic Liquids
WATER IN WOOD
DISTRIBUTION OF WATER IN WOOD
WHAT SEASONING IS
Difference between Seasoned and Unseasoned Wood
Manner of Evaporation of Water
Rapidity of Evaporation
Physical Properties that influence Drying
ADVANTAGES IN SEASONING
Prevention of Checking and Splitting
Shrinkage of Wood
Expansion of Wood
Elimination of Stain and Mildew
DIFFICULTIES OF DRYING WOOD
Changes rendering Drying difficult
Losses Due to Improper Kiln-drying
Properties of Wood that affect Drying
Unsolved Problems in Kiln-drying
HOW WOOD IS SEASONED
Methods of Drying
Drying at Atmospheric Pressure
Drying under Pressure and Vacuum
Drying by Superheated Steam
Impregnation Methods
Preliminary Treatments
Out-of-door Seasoning
KILN-DRYING OF WOOD
Advantages of Kiln-drying over Air-drying
Physical Conditions governing the Drying of Wood
Theory of Kiln-drying
Requirements in a Satisfactory Dry Kiln
Theory and Description of the Forestry Service Kiln
Underlying Principles
Objects of Kiln-drying
Conditions of Success
Different Treatment according to Kind
Temperature depends
Air Circulation
Humidity
Kiln-drying
Kiln-drying Gum
Kiln-drying of Green Red Gum
TYPES OF DRY KILNS
DIFFERENT TYPES OF DRY KILNS
DRY KILN SPECIALTIES
KILN CARS AND METHOD OF LOADING
HELPFUL APPLIANCES IN KILN-DRYING
The Humidity Diagram
Examples of Use
The Hygrodeik
The Recording Hygrometer
The Registering Hygrometer
The Recording Thermometer
The Registering Thermometer
The Recording Steam Gauge
The Troemroid Scalometer
Keep Records of the Moisture Content
The Electric Heater