Herman Hjorth "HOW TO OPERATE YOUR POWER
TOOLS", Home Craftsman 19, no 1 Janauary-February
1950, pages 18+
In the article posted below, Hjorth extols the
virtues of the two models of Radial Arm Saws that were available
in the late 1940s: respectively, Delta -- the Double-Arm
Multiplex -- and Dewalt -- the Power Shop.
(Manuals on these machines did not appear
until 1956: Robert Scharff's Easy Ways to Expert
Woodworking New York: McGraw-Hill, 1956 and an
anonymosusly-authored Getting the Most out of Your Radial
Saw Pittsburgh: Delta Power Tool Division, Rockwell
Manufacturing Company, 1956.)
Below are the oldest entries on radial saw in the Reader's Guide to Periodical Literature retrospective database.
Look at the dates with a little skepticism, i.e., 1952. Why? Because RG
does not index every article published in all the periodicals it
indexes. Regardless, it is in the early years of the 1950s that the RAS
saw is marketed to the homeowner.
1.
Brown, S. Radial saw. Popular
Mechanics v. 97 (April 1952) p. 218-23 2.
Andrus, J. F. How to use a radial-arm
saw. Better Homes and Gardens v.
31 (October 1953) p. 296+ 3. Francis, D.
Saw that does 'most everything [radial-arm power
saw]. Popular Science v. 164 (May
1954) p. 208-12 4. Pfister, H.
R., et. al., Two ways of getting the most from a
radial saw. Popular Science v. 173
(December 1958) p. 5.
De Cristoforo, R. J. Check your radial
saw for accuracy. Popular Mechanics
v. 110 (August 1958) p. 181-184 6. Oldest
radial saw gets newest look. Popular
Science v. 174 (June 1959) p. 174-5 7. Waggoner, W.
G. Power lift for a radial-arm saw.
Popular Science v. 176 (May 1960) p. 160
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In Hjorth's
January/February 1950 article in Home Craftsman, a
much younger woodworker than Herman Hjorth is pictured.
(The article is one of several Hjorth authored
for Home Craftsman over about a 12 month period. Another
Hjorth article is discussed in the entry,
Shaper. Hjorth died in 1951, bringing to an end a
long,distinguished career in woodworking teaching and writing
that covers from the 1920s until the beginning of the 1950s. In a book dated 1950, the Associate Editor of HC, Milton Gunerman, published How to Operate Your Power Tools. With
its index, this book is 224 pages longs, with 18 chapters. The chapters
are in the same text as Hjorth's articles. Also puzzilng is the claim
in the book's "Preface", ...The preparation of the book was supervised by Mr. Harry J. Hobbs,
editor and publisher of the Home Craftsman Magazine, following a
suggestion of Consulting Editor Arthur Wakeling....
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THE RADIAL SAW
By
HERMAN HJORTH
Author of Machine Woodworking,
Operation of Common n Woodworking Machines, Basic
Woodworking Processes, etc.
THE radial saw, which is a
relatively new form of the bench saw, is
becoming more popular because of its versatility.
This saw can be made to do all the operations
that can be done with the bench saw as well as many
operations that can be done with the drill press,
shaper and router machines. As a circular
saw its main advantage is found in the fact
that such operations as crosscutting, bevel
cross-cutting, mitering, compound mitering, dadoing
and tenoning can be done by moving the saw
while the wood remains fixed or stationary.
Radial saws can be obtained in bench
and floor models as shown in Figs. 1 and 2. In both
models the saw unit is of the same type. To convert
the bench model into a floor model, a base can be
purchased or made by the craftsman.
The various manufacturers have
incorporated special features in their radial saws,
but they are all alike in basic design and
operation. The saw unit consists of a base to which
an upright post is secured. This post carries an arm
overhanging the base, to which is attached a yoke
that cradles the motor. The saw blade is attached
directly to the motor shaft.
One manufacturer has gears built into
the motor so the shaft to which the saw is attached
is below the center of the motor. This design
permits the use of a smaller diameter saw blade
without reducing the maximum depth of the cut.
The arm can be raised and lowered in
the post to vary the depth of the cut. This arm can
also be swung in a horizontal plane in order to
permit crosscutting at any de-sired angle. The
motor, which is cradled in the yoke, can be rotated
from a horizontal position to a vertical position,
passing through a quadrant of 90° to permit the
cutting of a bevel within this range.
The radial saw shown in Fig. 1 is
designed so that the motor yoke travels in a
horizontal plane along a track, while the one shown
in Fig. 2 is secured to the forward end of an arm
that can be moved forward and backward.
Crosscutting. When
crosscutting on a radial saw as shown in Fig. 3, the
track or ram must he set at right angles to the
table fence. The bevel scale, which is found on the
yoke where the motor is cradled, should be set for a
zero position. The supporting arm should be raised
or lowered until the teeth of the blade just clear
the surface of the wood table.
When crosscutting, always use the
front fence. The motor is pushed to the back of the
unit, then the stock to be cut is placed on the
table and held firmly against the forward fence to
avoid shifting. The power is turned on and the motor
given sufficient time to attain top speed. Then the
motor is pulled forward with a steady motion until
the cut has been completed. After the cut has been
made, return the cutting head behind the fence.
There are several precautions that
must be kept in mind when using a radial saw. Never
allow the saw blade to walk through the work too
rapidly. Never attempt a cut by pushing the saw
blade back through the work. Be sure the edge of the
stock that is against the fence is straight,
other-wise the angle of the cut will not be
ac-curate. Line up the location of the cut with the
saw blade before turning on the power.
Bevel Crosscutting. Bevel
crosscutting shown in Fig. 4 is similar to plain
cross-cutting. Set the track or ram at right angles
to the front fence, then revolve the motor in its
yoke to set it at the desired angle. Hold the stock
firmly against the front fence during this
operation. The blade guard will have to be removed
when making a cut of this type.
Mitering. Mitering, shown in
Fig. 5, is the same as crosscutting with the
exception of the setup of the arm or ram. Instead of
the arm being set at right angles to the fence, the
arm or ram is revolved on a horizontal plane to the
angle of the miter. As with crosscutting, the stock
to be cut is held securely against the forward
fence. When mitering, the stock has a tendency to
creep toward the saw blade, resulting in an
inaccurate cut. To pre-vent this, the work should be
clamped to the table or fence with a handscrew or
Compound Mitering. Compound mitering, shown in Fig.
6, is a combination of bevel crosscutting and
mitering and is accomplished by setting the arm or
ram at the desired angle of the miter, then rotating
the motor in 'the yoke to the desired angle of the
bevel. As with mitering, the work should be clamped
to the fence or table to prevent the stock from
creeping.
Ripping. When using the radial
saw for ripping stock, it will be necessary to swing
the motor at right angles to the fence so that the
saw blade will be parallel to the fence. On radial
saws of the type shown in Fig. 2, this is done by
swinging the motor yoke 90°. On the model shown in
Fig. 1, it will be necessary to swing the track in
order to produce this setup.
Whenever possible, the front fence
should be used as the guide for ripping stock as
shown in Fig. 7, but the rear fence can be used as
the guide for wide ripping. The saw should he set to
rip to the required width by using the scale
provided on the arm or ram or by actually measuring
the distance from the fence to the inside point of
the saw tooth. After setting the saw, all parts
should be locked in place, as an operation of this
type requires the moving of the stock rather than
the motor as is done in crosscutting.
The stock to be cut should be fed
into the saw against the direction of rotation. This
may be either from the right or left depending on
the relative positions of the saw blade and motor
when the machine is set up for this operation. When
the motor is in back of the saw blade as shown in
Fig. 7, the stock is fed from the left to the right.
On some models the position of the motor for this
setup is in front of the saw blade. With such a
setup the feed must be from the right to the left.
Bevel Ripping. Bevel
ripping requires a setup similar to that of plain
ripping with the exception that the saw blade and
motor is tilted at the angle desired for the bevel.
This is done by rotating the motor in the cradle.
Figure 8 shows this operation being done on the
radial saw. As with plain ripping, always feed the
work with a smooth, steady motion against the
direction of the saw teeth.
Dadoing. Dadoing on the radial
saw can be accomplished with much greater ease and
more precision than on the bench saw. The reason for
this is found in the fact that the layout and saw
cut are visible at all times.
Figure 9 shows the radial saw being
used to cut a dado at an angle other than 90°. In
this same photograph can be seen two dadoes that
have been cut at right angles to the edge of the
stock. Setting up the radial saw for dadoing is
identical to the setup required for crosscutting or
mitering.
A dado head of required width is
mounted on the arbor in place of the regular saw,
then the entire unit set to cut at the depth
required. Straight dadoing or dadoing at an angle of
90° to the edge can be done without the need of
clamping or securing the stock to the table.
Whendadoing at an angle other than 90°, it is
advisable to secure the stock to the table with a
clamp in order to prevent the creeping of the stock
as the cut is being made.
Grooving. The operation of
grooving or making a slot with the grain can also be
done on the radial saw by using a dado head. This
operation is shown in Fig. 10. The motor is revolved
in the cradle or yoke until it is in a vertical
position with the saw blade at the lower end. The
motor unit is placed behind the forward end with the
blade projecting beyond this fence equal to the
depth of the groove.
Plowing a groove, either straight or
beveled, on wide pieces of stock can be done as
shown in Fig. 11. The setup for this operation is
identical to that of straight ripping or bevel
ripping with the exception that a single head is
used in place of the regular saw blade. With this
setup the depth of the groove is controlled by
raising or lowering the entire unit.
Rabbeting. Rabbeting can also
be done on the radial saw with the aid of a dado
head as shown in Fig. 12. This photograph shows a
rabbet being cut at an angle. For this operation the
motor is set up in the same manner as was described
for grooving. To cut a beveled rabbet, it will be
necessary to tip the motor to the required angle,
while for straight rabbeting the motor should be in
a vertical position.
Routing. The versatility of
the radial saw is found in the fact that it can be
used for purposes other than sawing. Figure 13 shows
one of these operations. In this photograph the
radial saw is being used as a production router. For
such a con-version, some form of adapter will have
to be used to take the router bit. The manufacturer
of the particular saw can supply the necessary part
for this conversion. The operation requires the
setting of the motor in a vertical position as shown
in the photograph, then adjusting the height of the
unit to produce a routed groove of the depth
required. By swinging the track or ram to whatever
angle the groove is to be made, no difficulty will
be found in producing a clean, straight cut.
Because it can do so many different
types of work and can handle long boards and heavy
planks as well as light work, the radial saw is
gaining popularity as a home workshop machine. It is
a money saver in profit shops and a great aid to the
man who is building his own home or doing any
important construction work.
Since all radial saws are constructed
so that the power unit can be moved in any direction
on a horizontal plane, it is possible to do freehand
routing by following an outline marked on the work
and taking light cuts. In freehand routing the ram
or arm is not locked; in all other operations,
however, it must be kept tight.
Molding. Another use to which
the radial saw can be put is that of molding. Such a
conversion requires the use of an adapter and a
molding cutter head. Figure 14 shows such a setup.
The motor is placed in a vertical position behind
the for-ward fence while the stock being molded is
passed in front of it.
The three-wing cutters familiar to
most home craftsmen and used on the spindle shaper
may also be used for cutting moldings on the radial
saw. Such a setup will require an adapter of some
form. The particular adapter will depend on the
machine that is being used and can be supplied by
the manufacturer. The adapter may consist of a
threaded arbor which is fastened directly to the
motor shaft, or it may consist of a three-jaw chuck
which is placed on the motor shaft in which an
auxiliary spindle adapter to take the cutter is
inserted.
Molding operations on thin stock
which will require the placement of the cutter near
the surface of the table must have a space provided
in the fence. A setup such as this will also require
the cutting of a hole in the surface of the table in
order to provide for passage of the arbor or spindle
on which the cutter is placed.
Another molding operation that can he
accomplished on the radial saw is that of panel
raising or the cutting of fielded panels as shown in
Fig. 15. This operation requires the use of a panel
knife while the motor is set at an angle slightly
off the vertical.
Boring. At least one
manufacturer of radial saws has designed a
drill-press attachment that can be set up on this
machine for the purpose of boring holes. Figure 16
shows such a setup. This setup permits the boring of
holes at any angle as well as in any direction.
Since the motor and drill-press unit can be rotated
through a quad-rant of 90° on a vertical plane while
the arm which carries the motor can be rotated in a
quadrant of 90° on a horizontal plane, any operation
that can be done on a standard drill press can also
be done on a radial saw that is provided with a
drill-press attachment.
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