Music Trade Review

Music Trade Review -- © mbsi.org, arcade-museum.com -- digitized with support from namm.org
MARCH 13, 1926
THE MUSIC TRADE REVIEW
43
The Technical Department—(Continued from page 42)
Home Study Course in
Lumber Kiln Drying
University of Wisconsin Prepares Course in
Co-operation With Staff of Forest Products
Laboratory
A new home-study course in the kiln drying
of lumber has been announced by the Extension
Division of the University of Wisconsin with
the co-operation of the Forest Products Lab-
oratory. The course, consisting of ten lessons,
is intended for the practical kiln operator, but
is also of value to the superintendent, the shop
foreman, and others interested in good kiln-
drying practice. It is written in simple lan-
guage and contains the latest information on
such important subjects as prevention of case
hardening, when and how long to steam lumber,
testing lumber to see how drying is progressing
or if it is properly dried, drying schedules for
all important kinds of lumber, kiln construction,
kiln instruments, and care of lumber before and
after drying.
The text has been prepared by Arthur
Koehler and Rolf Thelen, both of the Forest
Products Laboratory, where marked advances
in research of the seasoning of wood have been
made in the last decade. The following head-
ings indicate the scope and practical usefulness
of the. subjects covered by the course:
Lesson 1. General.—A discussion of the pur-
poses of seasoning lumber; difficulties encoun-
tered; economic importance of kiln drying prac-
tice.
Lesson 2. The Structure of Wood in Relation
to Its Drying.—How pores, rays, sapwood,
heartwood, plain-sawed lumber, quarter-sawed
lumber and structure of cells affect the drying
rate.
Lesson 3. The "Sap," or Moisture Content,
of Wood.—How moisture content is determined;
effect of moisture on wood; fiber-saturation
point; absorption of moisture from water and
atmosphere.
Lesson 4. Shrinkage and Collapse.—Cause,
variation and reduction of shrinkage; checking;
cupping; twisting; honeycombing; collapse; a
detailed discussion of cause and elimination of
case-hardening.
Lesson 5. Types of Dry Kilns.—Evolution of
kilns; advantages and disadvantages of differ-
ent types of kilns; description of commercial
kilns.
Lesson 6. Heat in a Dry Kiln.—Why neces-
sary, how supplied; types of steam coils; head-
ers and radiators; condensation traps; air relief
valves; thermometers; thermostats; boiler ca-
pacity required; temperatures recommended.
Lesson 7. Humidity and Evaporation.—Why
humidity is necessary; how relative humidity is
determined; control of humidity; humidities
recommended; when and how long to steam
lumber.
Lesson 8. Circulation and Piling of Lumber
in a Kiln.—Why circulation is necessary, how
produced; circulation in different types of kilns;
rate of circulation desirable; how rate is meas-
ured; how to pile lumber and other wood prod-
ucts in kilns.
Lesson 9. Kiln Selection, Layout and Con-
struction.—How to select kilns; location and
layout of kilns; storage and tracks; construction
of foundations, walls, roofs, ceilings and doors;
painting; insurance.
Lesson 10. Operation of a Dry Kiln.—In-
struments recommended; precautions; placing
of samples; calibration of instruments; prelim-
inary steaming; making observations and tests
during drying; keeping records; drying schedule
for different kinds and thicknesses of lumber;
factors affecting the drying rate; effect of kiln
drying on the strength of wood; care of lumber
before and after kiln drying.
Additional information may be obtained from
W. H. Lightly, University Extension College
Division, Madison, Wis. The fee for the course
is $10, with an additional registration fee of $2
outside of Wisconsin.
New Straube Patent
WASHINGTON, D. C, March 8.—The Straube
Piano Co., Hammond, Ind., is the owner
through assignment by William G. Betz, same
place, of Patent No. 1,574,863 for a string plate
for grand pianos.
This invention relates to string plates for
grand pianos, an object being to provide an
improved and simplified construction of this
character. A feature of the invention is the
provision of an improved and simplified pres-
sure bar construction which is preferably ar-
ranged as an overhanging extension of the
main frame of the string plate and positioned
above the hammer opening and arranged so that
the strings extend horizontally above the ham-
mer opening and held by the supporting por-
tion of the pressure bar, after which the strings
extend backwardly through the supporting
means for the supporting member toward the
tuning pins.
New Piano Tool Catalog
Two new catalogs, having to do with mate-
rial and accessories, have just been issued by
Lyon & Healy, Inc., Chicago, 111., and are being
distributed to the trade. The one called "Piano
Tools and Materials" contains 125 pages and is
said to furnish a complete list of piano repair
tools, materials and repair parts. It is the pur-
pose of the house in issuing this booklet to aid
tuners, repair and service men by gathering
under one general head all the necessary items.
FREE BOOK of FACTS
contains profitable information for YOU on the utili-
zation of HARD MAPLE for Musical Instruments, from
harp construction to the making of rugged Pack ing Boxes
and Crates. It also describes the application of HARD
MAPLE in many other industries, and gives official
data and strength tests on all American Hardwoods.